Not another one!!

[Welder4956]

Well i don't normally do these introduction forum messages but here goes i have also posted this on another forum.

I am in the 30ish year old bracket and i have come to be connected with this site through researching my biggest project (next to starting a family).

I am going to build a boat. It will be in the size region of 65'. I intend to retire on it and see bits of the world that i have so far missed and will miss by building a boat. I am competent crewman trained which i did with the army some time ago. It is not so much the sailing i want but the sailing of my creation that I'm after.

My background to this project is that i have my own small engineering firm and have been a coded welder for the past 18-20 years. I have built a great number of things from F1 cars in the UK to oil rigs in Dubai. I am now well settled in New Zealand where i am bringing up my family and building a boat:D .

I am under no illusions and am aware that for every success story there is hundreds of failures. The things i need to get sorted and that i am spending the most time on are PLANS. I have done as much research as i can through the net on trying to buy ready made plans (just add money) to chartering my own designer and getting custom build drawings, and as such i still don't really know which way to turn. There is a massive price difference between some of the off the shelf plans that I'm just not sure where value for money and ripped off separate. As i have said the hull build is not my fear factor. I will be building from either alloy or steel, still to decide. Have heard fores and against for both. The interior is where things get shaky but i have a couple of good friends nearby who make wood sing so i will abuse them fully.

Well i think thats enough of an introduction for now. If anyone thinks there are some good threads to read or links to look at feel free to drop me a line. Please not all doom and gloom.

Wishing everyone a Happy new Year

Matt

[rasorinc]

here is a steel plan that has floor plans and has been built before. Just something for you to think about. Stan
https://www.boatdesigns.com/products.asp?dept=457
Here are some building pictures. http://www.glen-l.com/picboards/picboard16/pic794-frame.html

[Welder4956]

Thats the sort of thing i have been looking at. Nice design. I have also looked at the Roberts New York 65 and a Dix 64.

This is where i became confused as to where price stops being affordable and becomes excessive. Both the Roberts and the Loadstar are comparatively priced. Then you take the Dix design and suddenly the scale has jumped 20 fold. i.e. Roberts $1000AUS compared to Dix $6000US.

Where is the difference for a set of off the shelf drawings?

If there is a marked difference does it command that sort of factor?

Thanks

Matt

[rasorinc]

Ever troll for suckers???? I sent you a P.M.

[Welder4956]

Excellent only 2 more posts to qualify for PM. I need to have been a member for 1 day and have posted 5 messages to access PM. I hope this counts as 1 of them. Cheers rasorinc I'm sure the wait will be worth it.

[rasorinc]

if you do not get it send me an e-mail or P.M. stan

[Jarrod]

Dear Matt,

We're a locally based marine design firm, Mount Maunganui that is.

I'm more than happy to meet with you to discuss your desired vessel if that will help. Whether or not we provide a design or just provide further advise, we're all for helping out the local boaties.

I look forward to hearing from you.

[Welder4956]

Jarrod

Well it is as good a path to take as any. I would like to outsource locally if i need to at all. I intend to use NZ profiles for all the plate cutting. As a local business i like to use local business. I only need to put 1 more post and then i can PM you. Stay tuned.

Matt

[Tad]

Welder....

Why 65'....why not 55'....or 45'. The smaller boat will go together quickly and be far easier to handle in the out-of-the-way spots you hope to visit. The money saved will buy many nice hotel rooms.

If you think you will save money by building a boat forget it. Today's market is full of fantastic deals on used boats. There are 10's of thousands to choose from and sellers are desperate.

If you must build NC cut parts are the way to go, be aware that prices (for nested parts data) for this vary wildly. Also realize that the welded (and painted if steel) shell represents 20-25% of cost and man hours of the complete boat.

Amateur built boats, from designs intended for amateur builders, such as Bruce Roberts and Glen-L, are generally viewed by the marketplace as questionable. This is because the builder is unknown, again an existing boat from a reputable builder is a far better investment. I'm not saying there will be no problems, every boat has problems no matter who the builder is.

I know Bruce Roberts plans are full of mistakes/oversights, I don't know this about Glen-L but I imagine it may be a similar case. I believe the Dix designs have fewer problems because they have received more attention by the designer. It makes no sense for a first-time builder/beginning sailor to commission a new design, don't do it.

[whoosh]

hey welder I have built many of both, if you like to pm with email address will be glad to talk,

[Welder4956]

Thanks Tad now we are getting some conjecture. I will try to answer your points in order.

Why 65'....why not 55'....or 45'. The smaller boat will go together quickly and be far easier to handle in the out-of-the-way spots you hope to visit. The money saved will buy many nice hotel rooms.

Have gone for a larger boat due mainly to cabin facilities. I have 5 children and would like to share my experience with them if possible. They will be older and more in there own life by the time i have finished this project but i want to be able to offer the facility if they want to. Perhaps a sentimental way of looking at it but it is a consideration i want to take into account.

If you think you will save money by building a boat forget it. Today's market is full of fantastic deals on used boats. There are 10's of thousands to choose from and sellers are desperate.

I think i have already made my point on this but i will make it again. I am not doing this to save money nor make money. I want to sail MY creation. This is my epiphany my last glorious project before i sail into the sunset. I have wanted to build a boat since i first learned to weld. Now i am older and better grounded i.e. kids growing no mortgage and a steady little business. I intend to throw some chaos into things. Like i said i am in my 30s now so have some time to complete the task. I have been bending and shaping metal for other peoples designs since i was 15. Now this is for ME.

If you must build NC cut parts are the way to go, be aware that prices (for nested parts data) for this vary wildly. Also realize that the welded (and painted if steel) shell represents 20-25% of cost and man hours of the complete boat.

One of my suppliers is a company called NZ Profiles and they are the largest NC profiling company in NZ. If the plans don't come with NC nesting drawings i am fully capable of using either Auto CAD or Solidworks to make pattern part drawings to be placed in a nesting. Again I appreciate the hull is the easy part of the project and there is more to it than that. I have been following the 5 year project of 2 ladies and a Roberts design on the net with some interest. Project management is my grounding so time evaluation and costing has been shaping for the past 18 months. Very valid point though.

Amateur built boats, from designs intended for amateur builders, such as Bruce Roberts and Glen-L, are generally viewed by the marketplace as questionable. This is because the builder is unknown, again an existing boat from a reputable builder is a far better investment. I'm not saying there will be no problems, every boat has problems no matter who the builder is.

This is something i have noticed from reading many posts. But there are a lot of these boats still in service today. The designs all seem to be very dated though. From the web research i have done i am finding the availability of plans to be very limited. A lot of people have an opinion on why i shouldn't get a Roberts or the likes but very few has offered any good reasoned alternatives. I have several boat builders on my door step here and i would look at going in and offering my welding skills in exchange for some boat building teaching. But being as i don't even have a plan to look at yet that bridge is still in the distance. Believe me they are screaming for welders over here boat building or otherwise.

I know Bruce Roberts plans are full of mistakes/oversights, I don't know this about Glen-L but I imagine it may be a similar case. I believe the Dix designs have fewer problems because they have received more attention by the designer. It makes no sense for a first-time builder/beginning sailor to commission a new design, don't do it.

So Roberts and Glen-L are "probably" full of mistakes Dix has "probably" got mistakes as well but less of them, and it would make no sense to commission a new design. So that being the case noting will get built. If you would like to suggest a solution to the problem you have highlighted but not on the open forum then please PM me.

I do appreciate your points and i am not trying to be argumentative. What i am trying to do is brainstorm through my issues with guys who have done this sort of thing before to arrive at the best solution.

I am an engineer and as such i see things as nuts and bolts and inches and millimeters. I also see that for every problem there is a solution it may just be a little awkward to get to. Right I'm sure that has opened up for more discussion and I hope productive. I have seen these threads get hijacked in the past.

Thanks Tad this all helps.

[Tad]

Welder...

Designs are like most things, generally you get what you pay for. I have been employed on several occasions to fix problems with Bruce Roberts plans. As with many things involving boats, it may be a matter of opinion as to whether something is a problem or not. But little things like no water tanks in the design or any place to put them...in a 55' trawler yacht. Or a propeller aperture that's too small for the indicated power. Or framing that's so light the deck oilcans when you walk on it.

Bruce Roberts and GlenL are producing plans (mostly) on spec, they do not have a client paying for the initial design. Consequently they put as few hours as possible into it. Understand that a complete 65' sailing yacht engineered to a modern standard would require approximately 1400 man hours. At only $50/hr that's 70k....considerably more than your stock plan price.

Recommended designers of metal sailing yachts in the 65' range...
Dudley Dix
John Simpson http://www.simpsonmarinedesign.com/
Ted Brewer
David De Villiers http://www.devilliersyachtdesign.co.nz/
Van De Stadt http://www.stadtdesign.com/
Graham Radford http://www.radford-yacht.com/

[welder/fitter]

Matt,
I bought the Lodestar55 patterns & plans 2 years ago. Ken Hankinson was the designer; he sold his plans to Glen-L a few years ago. Because the full-sized patterns are included, lofting is removed from the construction process, though one may still loft from the offsets, if one wishes. There are a few changes/additions which I would/will make to the plans, however, I did lay the lines in my shop(auto) & have found nothing missing or seemingly incorrect. I will be building in Asia, the layout was to consider any flaws/modifications while still in North America. An example of "missing" components, would be a bow thruster - invaluable in a vessel of this size. If you can get your hands on designs of the late New Zealand designer, Denis Ganley, for a reasonable price, you may consider those, as well. If, in fact, you are able to, let me know how to do so, he created some very appealling designs. Feel free to contact me with any questions regarding the Lodestar plans.
Mike

[Welder4956]

Thanks guys some good food for thought. Those links Tad were excellent. Also did some digging with the Denis Ganley and have found a company in Auckland who have his designs. I have e-mailed them and will let you know if anything happens. Well I am less than 10 hours from the new year now so best be getting my drinking hat ready as it is hot out there today.

All have a happy and safe new year and we will see each other refreshed and ready for that boat project.

Thanks to you all.

Matt

[Wynand N]

The things i need to get sorted and that i am spending the most time on are PLANS.....

Matt, I have been building steel boats from 1981 as an amateur and turned pro in 1988 and the best advice I can give you is this;
1. Get a reputable designer that is freely available, either by phone, email when you need to clear something with him /her.
2. Make sure the plans are BUILDER friendly - don't get whitewashed with the promise of full sized patterns and all that crap - I never used then anyhow.
3. Lastly, if possible, use a designer that has built and owned one of his own designs at least.

So Roberts and Glen-L are "probably" full of mistakes Dix has "probably" got mistakes as well but less of them, and it would make no sense to commission a new design.

I have been unfortunate to have built two Roberts boats; a 40ft CC Spray and a 38ft Offshore and the plans lacked a lot of detail and left the builder to his own devices at times - perhaps that is the reason why so many of his owner built boats have been problematic with some structural failures, rudder assemblies comes to mind. Yip, the plans looks impressive with this massive tube full of cheap paper templates:(

About Dix; I have been fortunate built a few of his designs; the Dix 38 (which I incidentally commissioned in 1991) , the Dix 57 and the Dix 65 and am currently busy with a Dix 43 CC. All these boats can be seen on my webpage.

This probably gives me some authority to speak out about Dix's plans and all I can say is that they are first of all, very complete and builder friendly - Dix built a few of his own designs and one boat that comes to mind was "Black Cat" which he successfully raced in South Africa and the Cape to Rio races - so he knows what it is all about.
Furthermore, he is always available with advice and backup.

Yes, I hear the question coming, what is "Builder's Friendly"?
In short, easy to build with no impossible bends or curves. Accessibility to all places and ease of welding at awkward places and best of all, complete plans with lots of detail and when possible options available. For instance, The Dix 43 we had an option of building the hull either in 4mm or 5mm plate with notes on how to change the construction for the thinner plate.
As a side note; I had built a Mason steel design once and that was my greatest nightmare and I made a promise never to touch one of his designs again.

Matt, as for the price discrepancy in plans, remember you get what you pay for and price usually in most cases reflex quality...

I confess. The best ever plans I had worked with in the past was Van De Stadt's of Holland. Built a couple of 34's and a 40ft and these plans are excellent in every detail and nothing left to change:cool:

[MikeJohns]

I agree Wynand


Also, I think one of the key factors to look for in any offshore yacht designer is time offshore. Many designers have no experience of blue water cruising and It shows both in their designs and their design philosophy.

Experience teaches many aspects of practical design. Building and maintaining your own steel boat teaches you even more. In the shipbuilding arena you quickly learn to design so as to keep the welders onside. One thing I found with many plans for small leisure vessels was designs with no access whatsoever for a MIG gun in many places , and no welding schedule .

Many of the older steel designs were quite poor in many respects. Often only one vessel was built and I have seen some serious miscalculations.

Modern design methods are more reliable and it is much easier these days to accurately predict vessel trim, immersion, stability, performance and seakeeping using the computer based naval architecture tools we have.

There are many large vessels that are one-offs, providing the designer properly knows their trade the vessel characteristics can be designed to from scratch. Any proper professional should be able to design a reasonably conventional vessel to basic specifications with ease first time.

Where I see designers coming unstuck these days is more often with light displacement craft for a variety of reasons.

In Australia we seldom see Dudly Dix designs, Australias equivalent was Joe Adams with his performance cruisers, Pugh is very common too in the larger boat market. Both have retired. Ganly and Mason have also gone on.

The Van De Stadt plans are, and always have been considerably more professional than Roberts and more easily made compliant to survey and scantling requiremnts.

cheers :)

[Dudley Dix]

Thank you to the members who have commented in favour of my designs. It is not for me to comment much about the quality of information supplied by other designers except to say that it does vary greatly. I can give you background info about me and my designs and comment about some of the statements in preceding posts on this thread.

Plan prices do cover a wide range and it is only reasonable to expect quality to be related in some way to the price that you pay, nomatter what it is that you buy. My prices are not the lowest but they are also far from the highest. I recently exchanged emails with a foreign client who has previously built one of my designs and wanted to commission a new design. I could not fit in the work. He bought a design from another designer then contacted me again to ask again if I could draw a boat for him. He said that the price paid to the other designer was many times my fee and he had received minimal information.

Consider that the price for the plans is a tiny fraction of the total amount that you will pay out while building the boat. If you start with the wrong design, for whatever the reason, the rest of the money is immediately devalued by the error. You will lose far more than you have paid for the plans, whether they were priced high or low. A plan price of $6000 on a 65ft boat is 1-2% of the material cost of that boat. Why would anyone risk the outcome of a big investment project like a 65ft boat, in order to reduce the cost by 1%?

My origins in boat design come from the point of view of an amateur builder. The only design that I have built from another designer was to the van de Stadt 30ft Zeester, in the 1970s. It was while building that boat that I started my yacht design studies. The van de Stadt detailing was excellent and set the standard to which I have always worked with my designs that we sell to amateur builders. I have built my own designs from 8ft to 38ft and sailed many thousands of miles on protected and open ocean waters, almost exclusively on my own designs. I have crossed the South Atlantic 4 times on my own designs. I have sailed for 55 years and surfed for 45 years. I have been around and on the water my whole life.

All of my metal designs were commissioned as custom designs by clients. After that they have become part of our stock design catalogue. All have been built and are sailing. Most have been built by amateur builders.

Everyone on this earth makes mistakes. Anyone who says that he does not make mistakes is not being honest with himself nor anyone else. I still have occasional dimension errors pointed out to me in designs that have been built by 30 or 40 builders in the past, without anyone pointing out the error. When errors are pointed out I correct them on the drawings.

Don't believe that computers eliminate errors. They reduce the amount of button pushing so finger trouble is less likely. Finger trouble with a computer also creates errors. Computers do make it quicker to do calculation tasks, so it is possible to draw a bad design more quickly just as it is possible to draw a good design more quickly.

CAD is essentially only a drafting tool. It is faster than hand-drafting in some respects and way slower in other respects. Overall, I know that a design takes me longer if designed in CAD than by hand. The benefit of CAD is that it sets up the design to be suitable for many other computer related design features, like CNC cutting of parts, accurate printing of full size patterns, preparation of 3D perspective views before building etc.

Despite the benefits available from CAD designs, I estimate that 80-85% of the plans that we sell are for building from scratch, with the builders wanting neither full-size patterns nor CNC kits. We offer full size patterns for most of our designs to those who want to go that route. Most choose to do it all for themselves, each for his own reasons.

The internet is great because there is a wealth of info available but as much as there is a mass of good info, there is also much put out as truth that is far from it. Some of the loudest opinions are from people who spend their time giving advice about all sorts of practical issues rather than actually practising the things about which they give advice. Be sure that the advice that you take is from someone who really knows the subject from personal experience.

In the end, you and your crew will have to live with your design choices. Whether you build a design from my catalogue or someone else's, be sure that your choice is for the right reasons.

[whoosh]

i tried to get your correct mail, I dont wish either to sell you a plan or build you a boat,
But 5 years ago I started a book, here is a rough draft of the first few lines in chapter one.Nice post by D Dix we disagree only on one thing, take a look at the gallery of lazeyjack see how a build can be set up to build quicker, then may pay to go to look at this boat in pic in Kumeu, I consider this small yard to be the best builder of metal I have seen anywhere in the world, and I have been all over Bos and carr, they do have a website in NZ and Wynard is correct abt the pattern stuff, patterns are for dressmakers and you will need draw parts of the boat, body plan, stem and cl bars full size on loft anyways, wont go into that here though
the book also covers building in metal without stringers in the main, from stretching forming to how to build your own gear, with big chapter on machines and welding from many years hands on experience
You are welcome to it for free, as I wont be finishing it
Chapter ONE the design

Maxim number one, it is as easy and costs no more to build a stunning yacht with sweet lines as it is to build an ugly dog of a yacht.
Did you know that to build a true round bilge yacht would only take 200 hours more than a chine yacht? 45-55 ft. Of coarse one will need to invest in a little more equipment, but at the end, the yacht will be a pleasure to look at, will be admired by all and will be worth 2 or 3 times what your chine OR unamed design \might fetch if built to a very high standard
My advise is to learn to understand the lines, never ever attempt to simplify the compound curves in a design, this seems to happen only in Australia where the marinas are full of the most ugly dreadful creations, not all of them home built I might add.


Most everyone will have an idea of his dream boat, in his head; chances are it has been there for a long time, in my case with my first serious cruiser it was. In hindsight it was the dead wrong thing to do. And here is why.
When a designer is chosen he should be chosen not from sentiment, in other words all of his boats have tan sails, and are yawls or ketches, and have long overhangs and long keels and turned posts in the salon. If you do this, you have a boat that hardly anybody wants, that goes to windward like a pig, if at all, that is slow down wind because she has that short waterline, and because she makes lots of leeway, maybe because of her keel. But worst of all when you come to sell her, she will not fetch much, she will have cost more to build because more than likely her displacement will be greater than modern types, and displacement cost money. Bigger rig to push her, bigger gear to handle the sails, bigger engine, more fuel, the list goes on and on, and here don’t get me wrong, you can still have volume in a boat, still have the room, without the weight. Of course there are some beautiful replicas and look alike still being built, but times move on, and by and large one is better of with the long waterline light/medium displacement yachts of today. Today’s yacht is not evolving much, at least in the underwater style, which seems to have really stabilized
You can have a 43 boat that weighs in at thirty tons and a 60-foot boat that weighs in at 26 tons
Now which would you prefer, one sails to windward at 2 knots, one sails at 8 knots, one takes forever to get there, gets trapped in bad weather systems, spend twice as long at sea and is a dog to sail, the other powers away, is a pleasure to sail, is lively vibrant looks a million


So how do you pick a designer, architect?
I have always put them into brackets
Amateurs
Does not earn main part of his/her living from designing Sometimes can, design lovely yachts, after all, Farr was once an amateur, these people can have a feel for a good boat, they may be serious racing people with a wealth of wins on the water and have drawn themselves a boat. Sometimes one can get a good set of lines from such a person, but you wont get a construction drawing, you wont get engineering input into the calcs and above all you will not get A NAME.
Professional Amateur
This is the worst ever scenario, you have a guy who sells lots of plans, they are usually of chine yachts, but not always, he has no qualifications and 99 per cent of the time the whole thing ends up a disaster, some of the things that can and do happen are, boat trims by the bow, that is she is down by the bow, this looks bad, worst still she floats with her boot topping a foot under the water, it happens, it happened in Auckland to an early superyacht, down 18 ins by the bow, there were 5 tonnes piles of lead all over the deck as they tried to figure out what to do!! Of coarse the architect blamed the builder, but I know he was just ducking for cover,
Other common scenarios are, bad sheer lines, bad sailing ability, e.g. weather helm, poor performance. Poor engineering design that is the structural, engineering, and all manner of other faults. Fortunally these designers shy from alloy, most likely they are banging out steel boat plans. Stay right away from them, the cheap initial cost of the plans will seem like peanuts when you try to fix the mistakes and when you come to resell.

Amateur Professional

Difference from above, he may not seek the major part of his living from yacht design, but have a love of the subject and maybe highly qualified in a related subject like mechanical engineering, architecture of buildings chances are you will get a good workable design here

Lastly the professional, professional
The p.p. designs full time, his yachts are known worldwide and the fees are what you would expect, high for someone who needs to work to a budget
What you should get is a design completed from start to finish. That includes, all working drawings, sailplans, keel plans, ballast arrangements, layout, furniture, stability calcs, which have become very important, especially for yachts that go offshore, or race, are intended for sale overseas, into the EC. In return for this, if the yacht is well built, you will more than likely find her easy to sell, easy to sail, easy to build. For a true international NAME expect to pay 100000 US dollars for 55 footer in 2002 money.
But there are people who are very very well regarded who can and do design for a quarter of this, say in NZ OR Australia. Some of the French designers, very experienced in metal fall into this category. I once asked one of the top superyacht design offices if I could design my own structure, as this is what I normally do, and they were willing to let me do this, firms like Dubois, Farr, Frers, are all very approachable and will speak to you and sometimes advise you. There are many very good architects and access to these people through the net has made searching for your ideal so much easier
Within the professional area, there are qualified navel architects and those that have no letters after their name, usually called yacht designers

A good plan is to ask the office to supply names and contact numbers of people they have designed for, don’t stop at this, ask around, dig into each and every corner, after all you are about to shovel anything up to a million dollars of your hard earned, into a sailboat

I cannot reinforce this section on design enough; I have met so many broken hearted and broken pocketed folk that have gone the cheap way.
Often this results in legal action, in some countries, if threatened by legal action, the designer simply winds up his company and starts again under a fresh name, simple, and until the law changes to allow one to pursue such people, its buyer beware.
When contracting to buy a design, that is to have someone draw up a boat design, it is a good idea to put all of ones verbalizing into a written contract with the designer. Then both parties know exactly what to expect.

. A minimum would be
Lines and offsets, never, ever, accept lines or templates without offsets, even if they are computer offsets or offsets (called) off a hand drawn. plan.
The reason some designers do not want to release these offsets is because they think you may sell them on. Never take no for an answer, insist.
Some firms are churning out kitset plans, that is with cut files, even with these people you must insist that you receive the lines and the offsets


If they will not supply then go elsewhere.
Stability calcs, without which you cannot take the boat to charter or sell into Europe and without which you will ever be sure, will she right or not
as you can see I ended the paste here

[Dudley Dix]

There are strong opinions expressed in the post by Whoosh but strong opinion tends to close the mind to all other valid options. It also can lead astray those who do not have the experience to question the opinions. I believe in keeping an open mind.

I have viewed the gallery of lazyjack and visited the website of Bos & Carr. I see a very competent builder that is capable of producing quality work, probably competitive with quality boatbuilders elsewhere. Their technology does not look much different from what is used by many other yards.

I see that they use stringerless construction, transverse framed. There is nothing wrong with stringered (longitudinally framed) construction and it is preferred by the ABS yacht rules. It is normally easier and quicker for an amateur to build a fair hull with stringers.

A versatile designer can draw a successful boat to a wide range of concepts. What is pretty to one person is ugly to another. The Maine schooners cannot be described as modern by any standards but they are beautiful, they sail well and they are seaworthy. You are unlikely to get the lovers of these boats to go for modern hulls and there is nothing wrong with the concepts that they do like. There are sometimes valid reasons to design (or want) a boat outside of the modern norm.

I am not sure where Whoosh fits me into his design categories. For the record, I design lots of boats for amateur builders but I make my living 100% from designing boats and I don't charge $100K for a 55ft design. What is wrong with buying a stock design drawn by a competent designer? We all market our services and products in the way that we see as best for us.

Lines and offsets, never, ever, accept lines or templates without offsets, even if they are computer offsets or offsets (called) off a hand drawn. plan.
The reason some designers do not want to release these offsets is because they think you may sell them on. Never take no for an answer, insist.

Most of our designs are built from offsets. Those who choose to build from patterns have the offsets in their plan packages anyway. However, there are times when building from offsets is impractical so they are superfluous. Our lapstrake designs are all supplied with bulkhead patterns as part of the stock plan package because converting offsets into a properly shaped lapstrake hull is awkward. It is easier for the amateur to do so from patterns. If a builder asks me for lapstrake offsets I will not provide them. I have not even prepared a set for my own use and the builder certainly has no need for them. Like I said at the start, strong opinions close the mind to valid alternatives.

Stability data must be available and should be supplied if requested. However, they are theoretical and must be validated with inclining tests. Designers make assumptions on hundreds of issues when preparing weight schedules on which hydrostatic and stability info is based. They can be considered only as educated estimates. Differences in methods by different builders will change the displacement and VCG, so the inclining test is the only way to ensure accuracy for CE certification.

[whoosh]

to DD
I have no opinions of your designs or yourself, from my exp talking to others, you do a fine job
i have built on both stringers(power) girdars and tranverse frames alone
I would not pay 100000 for a design, BUT I have seen a lot of rubbish produced by some prolific sellers, and quite obviously I can not name here
I merely say beware Do your homework, same as if you were picking a builder.
i talked to you once and your mind was completely closed to building right side up, so there I found a strong opinion which was inflexible:))
And believe me it is easier right side up, not to mention so much cheaper and faster, saving on cranage alone may run into thousands on a big hull, you were also inflexible on this
Yes I have strong opinions, but I also have an open mind and at 62 years of age it is still open
CAD, well it takes over a lot of what we used do on the loft, so unless one is careful, the owner may pay a lot more for a custom design, I know just how long CAD takes, and the cost of cut files to cut all componants is very high, on that steel boat you see above was in order 50k, and she has dutch flats as framing
For another opinion on Bos and Carr ask Dashew they did a couple of hulls for him, alloy fully framed up
have a fine sleep over there, oh I thought you were S.A, but I see you are from USA

[whoosh]

here is a rhino 4 file of some sections I have had done in alloy the face of the belting is 16mm, I can supply at a good rate need pay for dies, can you use em, the rail cap is solid, so tapping heavy screws for fitting make s life simple

[MikeJohns]

Words of wisdom Woosh.


I don’t agree with Dudly about computers and I have some issues with the lack of engineering in the correspondence courses that provide diplomas and certificates in boat design. ( I must say I’m not including Dudly in this critique) but people looking for a design can protect themselves.

.....
Everyone on this earth makes mistakes. ………Don't believe that computers eliminate errors. ………. Computers do make it quicker to do calculation tasks, so it is possible to draw a bad design more quickly just as it is possible to draw a good design more quickly.

CAD is essentially only a drafting tool. It is faster than hand-drafting in some respects and way slower in other respects. ……………… The benefit of CAD is that it sets up the design to be suitable for many other computer related design features, like CNC cutting of parts, accurate printing of full size patterns, preparation of 3D perspective views before building etc. ...........

In the hands of a professional the computer is invaluable and it reduces the design spiral time and cost by orders of magnitude and it is now considerably more than a drafting tool. The computer can tell you a considerable amount about your proposed hullform early in the design stage providing you have the background to understand that analysis.

Important target coefficients can be instantly checked and the hull can even be transformed to a target coefficient in some packages. For a sailboat you can heel the hull and check the coefficients and waterlines instantly. We can predict with reasonably high accuracy just how a conventional hull will behave with a database of existing vessels that have refined our predictions. A one-off hull from a professional using the computer as an analysis tool is going to be a safe bet unless you are after the last 2% of a performance ULDB racing machine. Or unless they have not actually designed the boat completely and you build the hull at the start of the design spiral. (I've just seen this in a big catamaran)
As for errors; for the builder there is no longer error in offset tables so rife under hand methods. Properly set up spreadsheets have removed the weights and moments errors that used to plague the design office and be blamed on the builder when the boat trimmed so badly.

After the old methods, what-if scenarios using the PC are so easy as to still give me pleasure even after using them for 8 years. For example Curves of stability with free surface and tank placement, I can run 5 different configurations and check downflooding angles within an hour. In the past it took a day for each and there would be an error margin. I can change displacement, instantly check freeboard and produce curves of stability in minutes.

Old rules of thumb and ready reckoners have been replaced with decent naval architecture programs to the advantage of all.

These days with the naval architecture tools you will get a good conventinal hullform every time provided the designer does the job with due dilligence.

Whether it's structurally adequate might be another issue that depends on the designers and their training. The clients can protect themselves from structural design errors by using a scantling society inspection of both plans and construction.

Although some people might get hot under the collar about scantling society requirements it remains a very good quality assurance program for the hull to be built to and construction supervised by one of the societies. Not just a claim from the designer that it complies with a scantling society.

Engineers/NA's can submit specific design calcs to the scantling societies which replace the scantling rules.
Ted brewer and Van De Stadt both hired engineers, Roberts didn’t initially and I think it showed in his designs particulalry when people tried to get them into survey, that's where John Pugh picked up all the bigger sail boats in Australia for survey work since he was a marine eng himself.




On Chines

Woosh mentioned people banging out chined hulls and I'll comment on this since the most demanding designs are chined hullforms for sailboats as I have found.

To many chined hulls come from designers who simply convert a round bilge design to a conveniently placed chine with no thought to flow paths or induced turbulence. Interestingly properly placed chines can even be beneficial in reducing resistance but require more design work and like bulbs it is out of any computer design programs ability. Then you have to sketch the initial lines by hand and conduct model tests for a good result (even CFD is not up the job ). On a properly designed chined hull the chine dictates the hullform . A radiused chine is then a valid option but beware of initial round bilge designs that are simply chined. Radius chine ameliorates a poor chine placement as it reduces the turbulence of cross chine flow.
To many chined hulls come from designers who simply convert a round bilge design to a conveniently placed chine with no thought to flow paths or induced turbulence. Interestingly properly placed chines can even be beneficial in reducing resistance but require more design work and like bulbs it is out of any computer design programs ability. Then you have to sketch the initial lines by hand and conduct model tests for a good result (even CFD is not up the job ). On a properly designed chined hull the chine dictates the hullform . A radiused chine is then a valid option but beware of initial round bilge designs that are simply chined. Radius chine ameliorates a poor chine placement as it reduces the turbulence of cross chine flow.

[Dudley Dix]

to DD
i talked to you once and your mind was completely closed to building right side up, so there I found a strong opinion which was inflexible:))
And believe me it is easier right side up, not to mention so much cheaper and faster, saving on cranage alone may run into thousands on a big hull, you were also inflexible on this

I have built all of my boats upside down as personal preference but my metal designs are all detailed without prescribing whether they are built right way up or upside down. That does not make me inflexible on the subject. It matters only that the builder produce a good boat by whatever method he chooses.

Professional builders with whom I have worked and who have built both right way up and upside down have generally settled on upside down as being the best for them. It goes to prove that what is best for one is not necessarily best for everyone.

[whoosh]

I have built all of my boats upside down as personal preference but my metal designs are all detailed without prescribing whether they are built right way up or upside down. That does not make me inflexible on the subject. It matters only that the builder produce a good boat by whatever method he chooses.

Professional builders with whom I have worked and who have built both right way up and upside down have generally settled on upside down as being the best for them. It goes to prove that what is best for one is not necessarily best for everyone.

I have found , most so called Pro builders, although earning living from boatbuilding, are, in fact steelshop fabricators turned boatbuilder
I do not know of any who were and are only timeserved boatbuilders who build upsides down, and where do you stop, 50, 100 tonnes? The Germans and Dutch, masters never did upsides down, wonder why?
well there are many reasons, but I know that from long exp will never change a mindset in here
Will say that with ceramic backing and the modern mig that building upsides down has taken away the only one plus, and that was that was easier to grind off the outside of the shell plate
happy new year, Mike
nice post

[Dudley Dix]

Mike, I agree with pretty much all that you say. Yes, computers allow us to do a whole lot more and to do so in less time. As I said in my earlier post, the calculations go more quickly and they allow us to do more. However, for someone who does not know what they are doing they can design a bad boat more quickly than they will by hand. CAD will not stop it from being a bad boat.

My point about my designs taking longer by CAD than by hand refers to the drafting aspect. I take longer to fully detail a design with CAD than drawing by hand. Nevertheless, I have not hand-drawn a boat for about 20 years, the benefits of CAD outweigh the negatives.

I do disagree in part with what you say about radius chine shapes though. A radius chine with a small radius will comply with what you say about ameliorating flow over a badly shaped chine but a chine with a large radius is much closer to a full round bilge shape and flow will be closer to a round bilge than a chine hull. It remains a compromise solution but it does simplify construction somewhat.

[Dudley Dix]

I do not know of any who were and are only timeserved boatbuilders who build upsides down, and where do you stop, 50, 100 tonnes? The Germans and Dutch, masters never did upsides down, wonder why?

Boatbuilders are normally working with way less than 50-100 tonnes.

I attended a lecture given by Dutch designers at IBEX 2007 about quality Dutch boatbuilding. I asked why it is that Dutch builders prefer transverse framed when stringered over wider spaced frames is easier. The answer was that they had encountered strong resistance to stringered construction from Dutch builders. The builders have always used transverse framing and do not want to change.

This may be the same reason behind them continuing to build right way up. Difficulty of access for cranes to small family boatyards may also contribute. Whatever the reason, I believe that each builder should be able to build by the method that is more applicable to his situation.

Here in USA and in South Africa, crane hire is not a major input cost. Possibly it is different in Europe.

[Wynand N]

I have found , most so called Pro builders, although earning living from boatbuilding, are, in fact steelshop fabricators turned boatbuilder
I do not know of any who were and are only timeserved boatbuilders who build upsides down, and where do you stop....

I beg yours, I am actually a boatbuilder turned steel fabricator :confused:. In my country there is not a lot of work to make a living from building steel boats only...

I have built both ways in the past and in my humble opinion it is only a fool that would want to build a boat the right way up given the choice. Let me explain.

1. All work is done at a comfortable height- a hull upside down is not all that tall due to the keel the wrong way up.
2. All plates are handled, marked, cut and fitted in a downhand position, and also much safer that way eliminating possible injuries working with heavy plates above your head. Try to fit a plate above your head the "right way" up...
3. Use less people to handle the plating in a down hand position.
4. Most welding done in a downhand position and with the upright method most welds are done vertical and overhead which tends to be slower welds and as a result some distortion guaranteed, moreso on thinner plate hulls. Also easier to do more controlled quality welds downhand.
5. Most grinding and finishing also done downhand and at a comfortable height.

All in all Whoosh, you can easily save about 30% in time spent building upside down and still have some skin left on your knuckles. This time saved easily offsets the cost of a crane handsomely....
Better still, ask Dudley Dix how long it took me to built his 65ft from loft to a welded and grind hull ready for turning over - I do not want to blow my own whistle...and I dare any steel builder to produce a similar fair hull of that boat in the same time building the right way up - regardless of working crew. I had used a boilermaker, welder and two helpers only.

I attended a lecture given by Dutch designers at IBEX 2007 about quality Dutch boatbuilding. I asked why it is that Dutch builders prefer transverse framed when stringered over wider spaced frames is easier. The answer was that they had encountered strong resistance to stringered construction from Dutch builders. The builders have always used transverse framing and do not want to change.

This may be the same reason behind them continuing to build right way up. Difficulty of access for cranes to small family boatyards may also contribute. Whatever the reason, I believe that each builder should be able to build by the method that is more applicable to his situation

My personal view on this is that they are stuck in a comfort zone. The problem with this is that you tend to be stagnated and stays in that comfort zone. All I can add to believers of the old ways; be brave, get out of the box and see how wide the horizon really is :idea:

[Tad]

Well....lot's to cover here....a question about design choice leads into an argument about building right side up or upside down...it's all good fun.

On design criticism....I believe it is up to designers to criticize each others work, we are the experts and if we don't do it who will? How will potential owner's become educated in the nuance of design features unless the choices are pointed out by experts. I tell everyone making a decision on whether to build a particular design...ask the designer's peers if they approve....

Take the mythological 65' metal yacht that is the subject of this thread. Built of steel to a certain finish level every design will take roughly the same amount of material and labour. The labour difference in hull form (say chine vs round) is a drop in the bucket of man hours involved in completing a yacht. The advantage of the various "quick build" methods (kits, etc) is that it gives amatures something that looks like a boat quickly. Then they realize that all the finish, systems, interior, etc, takes most of the build time and can't be short-cut.

So ...to a given level the investment (man hours and material) is the same. You can build a Bruce Roberts design or a Bruce Farr design....this choice will establish the performance of your boat, and also the value of your investment (labour and money) forever! Of course there are other factors involved. Have Royal Huisman build the boat and you establish a value level, have Joe the welder down the street build her and you establish another value level. But it still comes back to who did the design. If Huisman built the Bruce Roberts design (which they will not do) it would have a lower value than a Huisman boat designed by Sparkman & Stephens.

I find it silly to state that traditional types (with tanbark sails) are somehow worthless and will perform poorly...bull!

I'm not sure which Dutch yards are building right side up? Huisman, Vitters, and Bloemsma Van Breemen are all building upside down. Generally on fairly closely spaced transverse frames. Years ago I tried to get Huisman to change, mainly to get more usable interior volume, but met a brick wall.

A couple of further small advantages when building upside down in metal. When doing your final seaming inside you are working in the dark and every little pinhole shows up as a spot of daylight. Thus it's easy to know where you are and what's been done. Also if you sand blast the inside while she's upside down, all the crap falls out on the ground, simple cleanup for paint.

[jim2021]

if you donot want to pay the fee you can learn boat design. all you have to do is to buy the book 'yacht designing and planning' by howard i. chapelle. you can learn to design in one week. even if you buy the plans you still have to do the lofting of full size which is essentially you are redisigning the boat in full scale. i learned myself to design and to prove to myself that it was a boat, i made a model of 4 foot and to my amazment it came out a beutiful boat,and to prove it will float i put it in the water and it was floating in a level line. i also designed and built an aluminum outboard boat 3 meters.i m not advertizing my self, i just want to show you that is doable if you want to go this way.so you will be in controll of every step of the proccess and you depend to no other person.
just a thought
jim

[whoosh]

tad
the tan sails bit, well maybe should have clarified, but instead of saying SILLY you should have realised was a generalisationj abt clunkers, the steel boat in pic is a wonderful schooner, with modern underbody and the paras where a draft
i have found that the most successful designers are the most approachable, like Frers and Dubois were more than happy to let me draw the structure, , but still I could not afford
i have found a lot of designers inflexible and far too sensitive, quite unable to take constructive input into a designs and methods
Of course in saying that the designer will not let joe welder play with his design, but you can bet myself, for one, bos carr and bigger guys like huisman, and alloy yachts say, draw the boat with frames only, or in case of alloy yachts stringers
I have also found that people do not talk much away from the forum board, not bothering to KNOW or understand another, its a pity, thats why I encourage dialogue through yahoo messenger or msn, or phone, I have made some staunch friends this way, one of whom I have co designed with using yahoo messenger as our base
as for the crane
you can turn over a ten tonne hull with 2 heavy chain blocks, one hook is taken to the top of the building, the other starts at the sheer, a wire is wrapped around the hull and the bottom hook raised while top is lowered, cost zilch

[Dudley Dix]

if you donot want to pay the fee you can learn boat design. all you have to do is to buy the book 'yacht designing and planning' by howard i. chapelle. you can learn to design in one week. even if you buy the plans you still have to do the lofting of full size which is essentially you are redisigning the boat in full scale. i learned myself to design and to prove to myself that it was a boat, i made a model of 4 foot and to my amazment it came out a beutiful boat,and to prove it will float i put it in the water and it was floating in a level line. i also designed and built an aluminum outboard boat 3 meters.i m not advertizing my self, i just want to show you that is doable if you want to go this way.so you will be in controll of every step of the proccess and you depend to no other person.
just a thought
jim

Please don't invite me to sail offshore with you in this boat that you have learned to design in a week. There are various books that explain how to design boats but you will not have acquired the depth of feeling for hull shaping to suit the ocean, which comes from years of sailing, designing and experiencing the results of those designs and the decisions that were taken all through the design process. Without that experience you have no certainty whether it is a good or bad boat that you are producing.

Yes, there have been good boats designed by amateurs but I doubt that you will find many that were designed by anybody with such brief self-education. The successful ones have mostly designed their boats upon a basis of years of sailing and observing/analysing boats.

Jim, design your boat, including the structural design, interior layout, joinery detailing, ballasting, rig, hardware layout etc. Detail it properly so that others can build it while knowing what is in your head, rather than you having minimal info on paper and designing on the back of a cigarette box as you build. That will show you what effort goes into a decent design. After that, build the boat and take it on an offshore passage to prove it. That is when you will learn whether or not the boat is worth the time and materials that you have put into it. If you have not had the required depth of knowledge at the start of the process, you may find that you have lost most of the value of your investment.

as for the crane you can turn over a ten tonne hull with 2 heavy chain blocks, one hook is taken to the top of the building, the other starts at the sheer, a wire is wrapped around the hull and the bottom hook raised while top is lowered, cost zilch

Whoosh, you have just strengthened the argument for building upside down.

I have turned all of my hulls with tackle but they were all built from wood, so quite light. Metal boats to my designs have been turned by the spitroast, hoop and other methods without cranes.

[whoosh]

I used to build my powerboats to 10m upside down, simple trailer inboards with large cokpits
when you move into bigger boats the deck should go on first
i often have people doing woodwork up forewards before the aft parts are finished welding
So may more men can get on with their respective disciplines right way up. The first 80 footer New Plymouth Eng did was upside down, as was the 90 of alloy yachts, that was the last ever
I am NeVER Going to get you to change, you simply will never see it. and I think the right way up scares you?
However I agree, with the point you made, abt designing a boat is a week, nonsense
I do not design hulls I leave it to trained navel architects, I do the structure and eng and electrical
I work with the architect to achieve what we both think is best
For instance on this one, the architect placed the traveller over the cockpit entrance!! blocking access to all but the young nimble, so I designed the arch, it works beautifully

[Dudley Dix]

I am NeVER Going to get you to change, you simply will never see it. and I think the right way up scares you?

Whoosh, how do I get this into your head? I am not against people building right way up. I design the boats. The builders build them right way up or inverted to suit themselves. The fact that the builders mostly choose of their own accord to build upside down says something about their beliefs but not about mine. I say "mostly" but it is probably more accurate to say "all", I am not aware of any who have built my metal designs right way up.

You will not be happy until I say that right way up is better. That is not going to happen. Let each man choose for himself.

[Wynand N]

you can turn over a ten tonne hull with 2 heavy chain blocks, one hook is taken to the top of the building, the other starts at the sheer, a wire is wrapped around the hull and the bottom hook raised while top is lowered, cost zilch

been there, done that and got a T shirt;)

Whoosh, I turned a Dix 43 with chain block tackle only without the luxury of overhead steel trussed to work from due to the flimsy smallish lip channel truss construction. The tackle was attached to the uprights of the building both sides of the boat and turned her over without a scratch. I attach a few photos showing that turn over.
If you look at the time lapse on the photographs you will see that from the lift started until upright took just 2 hours flat. But, take note - the lift was halted midway for photo sessions, some serious discussion with Mr Chivas to calm the nerves etc. Actual time taken for complete turn over about 1.5 hours.
BTW, this boat displaces close to 15 tons...

[whoosh]

been there, done that and got a T shirt;)

Whoosh, I turned a Dix 43 with chain block tackle only without the luxury of overhead steel trussed to work from due to the flimsy smallish lip channel truss construction. The tackle was attached to the uprights of the building both sides of the boat and turned her over without a scratch. I attach a few photos showing that turn over.



If you look at the time lapse on the photographs you will see that from the lift started until upright took just 2 hours flat. But, take note - the lift was halted midway for photo sessions, some serious discussion with Mr Chivas to calm the nerves etc. Actual time taken for complete turn over about 1.5 hours.
BTW, this boat displaces close to 15 tons...

tee hee, hello Wynand from your old mate, I,m a bit bored whose gor something for me to bild?
truce Dudley

[Welder4956]

Gentlemen thank you. I went away for a week with the family and have come back to quite a catch up.

Before i go any further i would just like to thank Jim for his suggestion but kindly decline. I am Mechanical engineer with both trade certified apprentice training and a Bachelor degree in Mech engineering. I have no misguided feeling that i am going to design a boat that will carry myself and my family through waters unknown, with 1 weeks training and a book. Sorry jim but i'm just not going there.

Dudley...I am pleased that you have an input on this forum and are ready to answer any questions that may be put to you. I will in the fullness of time contact you regarding the project that you have some insight to from this forum.

Being "Joe the welder" some of the trade terms and definitions took some serious Google and book research but i think i have a grasp of what people are trying to say.

I have had a look at some designs and have been talking to many boat builders and owners. Living where i do there are some well place drinking holes frequented by such people.

So if i give you a run down on what i have come to so far we can tear it to pieces.

It will be steel.
It will be 60' at least.
It will be round hull.

Now i know the last statement sent sputtering around the room as an amateur builder taking on a round hull is foolery. I am anything but amateur steel worker. I give you gentlemen due credit in your fields kindly do the same with mine.

The cost of the design is to an extent an issue but as an engineer i would like the best plans possible for a reasonable price. I am not the sultan of Brunei and as such chartering a designer from far away is not my aim. I am not worried about resale value that will be my kids problem, but I am concerned when it comes to getting the vessel surveyed for insurance and other such events.

I have heard many bad stories of Roberts design from all the boat builders in the area i went. I will not be looking Roberts. Ganley on the other hand got rave reviews and is a strong contender. Kiwis back him strongly. But like i say i am still looking. I will work this as any other contract i run. All options considered then price to quality. There is nothing more valuable to me than my family's lives and that is what is at stake if the design is not right.

Upside down or right way up? I like the idea of building from the bottom up but can see advantages to upside down. Not keen on welding it upside down, nice gas trap really. Not decided mighty be just a couple of fans to sort that out will make many other thing easier.

I have bought Colvins book on steel boat building and although some of the methods are a little dated by todays standards the principles are good reading. I have only read Vol1 so give me a chance.

Excellent gents i think i have waffled on enough.

Happy new year to you all.

Matt

[rasorinc]

On my posting I sent you building pictures. Another member chimed in that he has just cut out his steel hull--the same boat that I sent you the link on. The best advise I can offer is to contact these 2 individuals and have a dialog. They have and are building the same steel boat. Their wisdom I would think is invaluable and I know they would share their experiences. I am a Wood man and have built many boats but my knowledge is close to zero re: steel. I wish you all the success in the world, building your own is a great accomplishment and you will treasure the experience forever. Have fun and good luck. Stan

[Wittholz 35]

I used to own a VanDeStadt 34' in steel built by Doug Knight a contributor to the book Steel Away. In talking to Doug about building the boat he said that the plans were excellent. I know that the end result was an awesome sailing boat. I have the plans if you would like me to send you some pictures of them to get an idea of what to expect from VanDeStadt.

[Welder4956]

Thanks Stan. I will pester people no end shortly.

[ecflyer]

I am building a Roberts 434 in wood (cold molded) and I have never built a boat before. I found no mistakes in the plans and found them to be as detailed as I need them. I simply cannot understand all the bad press on Bruce Roberts. When ever I have had questions he has be avaiable to answer them within 24 hours. I have a friend Graham in Australia that is also building a Roberts 37 and he has not encountered any problems either. He does boat repairs for a living so is very much familiar with how boats are built.
I have never been on a sailboat, so I had to attend the Chicago sailboat show to get some idea how they are suposed to look when completed. Being a complete novice, I had to acquire over 50 boat building books in my library. After 2.3 years of construction time, I have completed the boat hull, deck, stern, pilothouse,keel, sole and interior partitions. I am now installing the 88 hp Yanmar engine and drive line. I have nothing but good to say about Bruce and so does my friend Graham. You people really confuse me!

Have a Spiffy Good Day !
ecflyer

[ecflyer]

I forgot to mention that I have another friend Lee Patterson who built a 42' Roberts trawler 20 years ago in steel. He also recommends Bruce Roberts whole heartdly. He say's Bruce is absolutely a great guy. My wood design is incredibly strong. I pounded on the deck in some places with a 2# hamer and it sounded like I was pounding on concrete or rock. His designs are incredibly strong.

G'Day Mate!
ecflyer

[Welder4956]

As i have neither owned, built nor sailed a Roberts i can not hand on heart give you an experienced answer. I can tell you what i have heard from some 10 to 15 boat builders.

Roberts produce "nice" boats but they are apparently unstable. The drawings are old and as such new technology and smoother lines are not employed. Now i have e-mailed the Australia branch and i will admit i found the response speedy and informative.

Bruce Roberts design have had some bad press, which from what i can see is mostly self inflicted. With people being told they have black listed boats and unregistered drawings. I see Roberts as a potential minefield from this perspective.

I was inquiring about steel hulls and big ones at that when i did my research i have had no imput from anyone about the wooden or smaller vessels and i would hope this thread does not turn into an attack on boat designs. I have to say the information i have had through this thread has been of the highest quality and as much open minded. No body has come on and said i must use this guy and not the other guy and i have narrowed my list to 4 designers. Although i feel 1 may not be able to provide the plans for the vessel i want.

I am absolutly certain that what you are building ecflyer will be as magnificent as you have hoped and the time and care you have put into it will pay off. Don't let what other people say confuse or deter your mood in any way. I would be very interested in knowing why you chose the Roberts design over the many others available to you? It would help in my search.

Thanks guys for the help and continued support.

Matt

[Tad]

ec is to be congratulated on building his boat, may she treat him well! No attacks just trying for honest opinion here. ec mentioned he is inexperienced, (that's allowed) and found no mistakes, good.... but an experienced eye may have a different opinion.

So I was thinking about this project over the Holidays and thought I'd see what could be done in the way of a modern cruiser (ketch) with a (2.5' constant) radius chine. Below is the result so far....66' LOA, 53'8" LWL, 18'6" beam, draft 7'6", displacement around 90,000 pounds.

28292

[Welder4956]

Tad thats a nice looking design. I was wondering the diffrence for short handed sailing with a single mast over the two you are showing on this design. I am definatly sold on having a central cockpit to allow lounging room on deck behind. I am also keen on a swim platform.

Have asked for study plans from Van de stadt and ganley. I have emailed graham Radford to see if he has something matching my ideas but have not been able to find study plans on DD web site. If he reads this before I can e-mail him I am seriously looking at the Dix 65 as a contender.

After a long discusion with a salty sea dog at Tauranga marina today while he showed me around his 55' Ganley design that steel is the way forward. For many reasons it is a beter and easier to maintain material.

Keep it flowing gents this has been invaluable.

Matt

[ecflyer]

Welder 4956, you would like to know how I decided upon a Roberts designed yacht. Before I can answer that, I need to give you a little background info on myself. I am a retired building contractor and as such have many years experience working with building architects. Navel architects are quite similar in almost every way. So after finding a design I liked, I sent for the introductory plans (which are not to scale), but in all other ways are exact. I found the plans to be very detailed so I purchased them. Now I admit that I probably do not need the detail of explaination that most amatures would need. As an example: I have increased the length of the boat by 7% which is 48". I have increased the size of many of the framing members and stringers. I am not an engineer, but do know structural strengths, stresses and strains. I have increased the over all strength of Robert's design with minimual increase in weight. My ultimate goal is not to go sailing, but my enjoyment comes from the building process. I am retired and this is my hobby. At the end of the day, I will have created a masterpiece that will put factory produced boats to shame. I had talked to a fella that had built a Roberts 434 out of steel and he sailed it around the world in 228 days. He said he often exceeded hull speed at 9 & 10 Knots w/o current assistance. He sold that boat and planned to build another Roberts design only larger. I have been a life long member of the experimental aircraft assoc and credit much of my engineering knowledge to them. I may be an amature boat builder but a very experienced builder of many things. I don't think anyone should start building a boat unless they have experience in some aspect of the build process. But then again, if one does not know how to perform a certain build task, then get a book and learn or ask someone. What is so difficult about that? I think building a boat is easy and fun but occaisionally requires a little foul language. Welder, you come across as a very educated person and my gut feeling is that you do not need the level of detail that a rank amature would need on the plans. Why spend $10,000 on plans when you can get what you need for $800. If you think the stability of a Roberts design is lacking then increase it. Build your steel hull and go with a wood deck. Place extra tankage and all tankage under the sole. Maybe add some lead at the bottom of the keel just to lower the center of gravity. Maybe reduce the height of the mast and add a bow sprit to make up for the lost sail area. If your an engineer, you can recalculate the center of effort of the sail area to ensure the weather helm remains constant. For the small price of approx $125 you can get introductory plans from Roberts and can see for yourself if they are up to your needs. Why rely on someone else's opinion? By the way, the Roberts plans sold out of Australia are stolen and incomplete w/o the latest drawing additions. Bruce lives in Spain. I wonder if some of your friends with poor experiences on the Roberts plans have gotten involved with the incomplete plans out of Australia? Good luck in your endevor!

G'Day Mate
ecflyer

[ecflyer]

Welder 4956, you would like to know how I decided upon a Roberts designed yacht. Before I can answer that, I need to give you a little background info on myself. I am a retired building contractor and as such have many years experience working with building architects. Navel architects are quite similar in almost every way. So after finding a design I liked, I sent for the introductory plans (which are not to scale), but in all other ways are exact. I found the plans to be very detailed so I purchased them. Now I admit that I probably do not need the detail of explaination that most amatures would need. As an example: I have increased the length of the boat by 7% which is 48". I have increased the size of many of the framing members and stringers. I am not an engineer, but do know structural strengths, stresses and strains. I have increased the over all strength of Robert's design with minimual increase in weight. My ultimate goal is not to go sailing, but my enjoyment comes from the building process. I am retired and this is my hobby. At the end of the day, I will have created a masterpiece that will put factory produced boats to shame. I had talked to a fella that had built a Roberts 434 out of steel and he sailed it around the world in 228 days. He said he often exceeded hull speed at 9 & 10 Knots w/o current assistance. He sold that boat and planned to build another Roberts design only larger. I have been a life long member of the experimental aircraft assoc and credit much of my engineering knowledge to them. I may be an amature boat builder but a very experienced builder of many things. I don't think anyone should start building a boat unless they have experience in some aspect of the build process. But then again, if one does not know how to perform a certain build task, then get a book and learn or ask someone. What is so difficult about that? I think building a boat is easy and fun but occaisionally requires a little foul language. Welder, you come across as a very educated person and my gut feeling is that you do not need the level of detail that a rank amature would need on the plans. Why spend $10,000 on plans when you can get what you need for $800. If you think the stability of a Roberts design is lacking then increase it. Build your steel hull and go with a wood deck. Place extra tankage and all tankage under the sole. Maybe add some lead at the bottom of the keel just to lower the center of gravity. Maybe reduce the height of the mast and add a bow sprit to make up for the lost sail area. If your an engineer, you can recalculate the center of effort of the sail area to ensure the weather helm remains constant. For the small price of approx $125 you can get introductory plans from Roberts and can see for yourself if they are up to your needs. Why rely on someone else's opinion? By the way, the Roberts plans sold out of Australia are stolen and incomplete w/o the latest drawing additions. Bruce lives in Spain. I wonder if some of your friends with poor experiences on the Roberts plans have gotten involved with the incomplete plans out of Australia? Good luck in your endevor!

G'Day Mate
ecflyer

[Wynand N]

I simply cannot understand all the bad press on Bruce Roberts....

ec, It was your first boat you had built and obviously as an amateur the first set of boat plans you you handled and any such person would be greatly "impressed" by any set of BR plans, moreso with that full size templates that's added.
However, I you you have handled plans from other designers, such as in my case, Lavranos, Dix, v/d Stadt, Ibolt to mention but a few, you will understand the relevance of the quote above...
Having said that, I wish you can see a set of v/d Stadt 34 or 40ft plans or any other by that design group - you will be stunned. As said before, v/d Stadt is my personal choice of plans to work from:cool:

As Tad said, congrats on having built and completed your boat by yourself and may she treat you well.

[Tad]

There are several reasons for going to a ketch rig in the above 66' design. One reason is that the mast positions, sheets, etc. work with the proposed arrangement. Perhaps a more important reason is ease of handling. 1800 sq ft of working sail is a lot, splitting it into 4 sails means more simple options for easy sail area reduction. The fore triangle of this yacht is 800 sq ft, the main is 650, and the mizzen 340. These are big, heavy sails. Without power furling they are right on the edge of (perhaps beyond depending on how athletic you are) possible for the average Joe. Yes, power furling is wonderful, but for the self-sufficient world cruiser it is endlessly problematic. I prefer simple manual gear though on a boat this size I would highly recommend a pair of powered (Hyd. or electric) self-tailing sheet winches someplace aft of midships. These can get you out of a great deal of trouble.

ec.....
I tried to explain in post #28 why one might decide to invest more in a particular design. You are a neophyte and can't see the difference between one design and another...okay....please understand that folks with considerably more experience are saying there is most definitely a difference! I'm afraid you will find this out when you try selling your boat. Besides differences in performance, looks, arrangement, ease of construction, and structural integrity, there are vast differences in the value of the finished product.

Have a look at the BR listings on Yachtworld.com, there are currently 90 of them. How is your boat going to stand out among all these? The BR designs are uniformly listed at below average prices for boats of that size, what could be the reason for this? First off no recognized builder, being of uneven quality (amateur built) lowers the value of the whole group. Even a badly built production boat is more valuable because it's a known entity. Nope...it makes little sense but that's marketing.

Again...being a neophyte you have "improved" the original design...a classic mistake. If the design had been done properly in the first place, your improvements would be unnecessary. Did you catch all the oversights, do all your improvements work together? As a buyer I have no idea. Please don't take this as criticism of your boat in particular, I have no knowledge of your project. I'm only trying to explain how (IMO) your labour might have more value when invested in a different project.

[ecflyer]

Tad,
I looked at the Yachtworld site at the Bruce Roberts designs for sale and I say I must agree with you whole heartly. I viewed the photos of about half of the 90 boats for sale, and I must say I was not at all impressed with the workmanship. 95% of the boats looked so unprofessional that I can't imagine anyone wanting to make such a purchase at even the lowest prices. My goal is to build a million dollar yacht. I can see I have my work cut out for me to distance myself from the pack reputation-wise. As far as the workmanship goes--well that will be simple to accomplish. The first step in marketing is that one must at least arise in the buyer enough interest for them to want to take a test sail. Appearance is of the utmost importance in that regard. If meticulous workmanship was used to create true beauty, then a normal person will tend to assume that attention to all details of construction were employed. I hope I can accomplish this; however, I do not plan to sell my boat. I want something to leave to my grandson---something fantastic that he can say his grampa built.

Have a Great Day !
ecflyer

[Dudley Dix]

Have asked for study plans from Van de stadt and ganley. I have emailed graham Radford to see if he has something matching my ideas but have not been able to find study plans on DD web site. If he reads this before I can e-mail him I am seriously looking at the Dix 65 as a contender.
Matt

I did respond to Welder4956 by private message but should also post this note for others. My plan and study pack prices are on the pricelist at http://dixdesign.com/priceabr.htm . There are links to the pricelist from almost every page on my website, from the navigation menu panel.

I am not sure why the "Prices" links are missed by many visitors, despite being prominent in the navigation menu. I guess that we all skim pages of information and sometimes miss what we are looking for.

[whoosh]

The starter of the thread asked me to explain what to do abt distortion when assembling a frame, least think was he:)

I did not care to do it but will even though I bet it get s flak from some

The frame may have many parts, if it is cut from a nesting CAD file maybe only two, the beam, and the sides, floor combined

Or it may have many, if you cut it, a two chined boat can have 8 parts not including gussets (brackets)
Anyways let’s tackle the most difficult

AS I said before this is why you need the body plan full size, and the offsets
So if you have 3 parts making up the sides of the frame, and a floor and a beam,
You cut out as accurately as possible, and the joints at the sides are made up of equal angles, in other words the joint is bisected,, make the joint tight but prepped out so your weld will be full penetration You can assemble these three pieces as one and then into the frame OR you can assemble the whole ring as one
Whatever you need to make sure the parts fit the loft exactly, flat bar is easier than angles, or t,s t,s are better to work than angles and so on

So if you make up the first way weight heavily the pieces, the in the centre if the joint run a short hot tack, let it shrink then take off the weight, if the weld has pulled so the frame come IN towards centre then put the next short hot tack on the outside of joint, run towards the centre!! Do the same on inside of joint. Check again, if it is outside the line or inside don’t worry yet
Prep out the ends of the tacks, with that thin wheel someone was talking of, then weld from both sides to the centre , keep the wells as small as possible but enough to fill the joint, second passes cause more distortion
Let it cool, check on loft, if the frame is inside the line, take a dolly put under weld and peen the end weld till the frame fits, it takes very little, if the frame is Outside the line pein the outside edge of weld
Turn it over, and do same
it is a good idea to place a pice sheetmetal under the weld, stops loft burning up

If you want to do the whole thing as one

Weight it all down, then short hot tack all the joints including the beam and floor working from side to side in other words do one tack one side then it opposite
It’s a good idea to use as much temporary bracing as you can lay hands on, like a strut from beam to floor
The key is fit up and watching the thing all the time, after awhile you will get hang of it, you can really get the weldment to do anything you want with time and experience, but you will be frustrated many times first)
Some rules say overlap frame to floor 21/2 times depth of frame, I don’t I usually reinforce that area in other ways, or when I do overlap , 2 times
i would give Ganley a big fat miss, and I am not afraid say so in here , even though he is no longer with us and I dont wish speak ill of passed people, but often his sheer lines look totally broken and quite obviously you won,t get help from above
i would go for the Dix boats from all thsoe that have come up here
on the other hand you may try Mike Johns in here, who is one of the worlds true gentleman, but only when you are really serious as he is quite busy:)

[Welder4956]

The starter of the thread asked me to explain what to do abt distortion when assembling a frame, least think was he

It wasn't but a nice addition to the thread I'm sure sir.

I had the pleasure of a walk around a 40' Ganley today down at the marina and must say she was a fine looking vessel. nicely laid out and really well finished lines. A testament to the yard that produced her, which i think was said to be in Auckland.

I have given Ganley a shot mostly because his work is well thought of among the local builders who have been most helpful. He is as you say contactable via a medium and as such not much of a reference point is available. Having said that one of the yard here has built several of his designs and are willing to help if the need arises. I'm sure there will be money involved but that is the same in all cases.

A question i would appreciate some help on is the need for full templates on mylar film. I have read in a previous post by wynand that they are a superior template but if i intend to get the items CNC profiled would i still need them?

One of the designers i am looking at supply these as a standard. If i have no use for them is it worth paying extra to have them?

[whoosh]

I use mylar film, in roll form, I never use cut files cos they are too dear and with alloy you can cut so fast with hand saw, but with the mylar you can pick up any dwg from the loft, lay on plate, centrepop the plate, and bobs your uncle
i once sailed a Ganley to Fiji, was 38 or thereabts pacemaker, was awful so much weather helm, a bit of a dog really
SO if you have the offsets and you have drawn your body plan , thats the use for mylar, , I have all the tanks floors on a roll right now for next boat
in this case used rhino ,
why dont you consider alloy? faster cheaper, less trouble
i dont think any of Ganleys stuff is on CAD? puter spsoed save time, but God do they ever gobble it up
sent you pm

[Dudley Dix]

A question i would appreciate some help on is the need for full templates on mylar film. I have read in a previous post by wynand that they are a superior template but if i intend to get the items CNC profiled would i still need them?

One of the designers i am looking at supply these as a standard. If i have no use for them is it worth paying extra to have them?

You are unlikely to need any patterns if you build from a CNC kit. Most builders of my boats build from offsets and bulkhead/frame diagrams, if building from scratch. A small percentage order Mylar patterns. Only some of our dinghies are built from paper patterns, they are too dimensionally unstable to use for larger boats.

i once sailed a Ganley to Fiji, was 38 or thereabts pacemaker, was awful so much weather helm, a bit of a dog really

Ganley designed some really nice steel boats. I have a lot of respect for his work. I have only heard good reports of them from owners. Whoosh's is the first negative comment that I have seen.

Dudley

[whoosh]

You are unlikely to need any patterns if you build from a CNC kit. Most builders of my boats build from offsets and bulkhead/frame diagrams, if building from scratch. A small percentage order Mylar patterns. Only some of our dinghies are built from paper patterns, they are too dimensionally unstable to use for larger boats.

smile, b



Ganley designed some really nice steel boats. I have a lot of respect for his work. I have only heard good reports of them from owners. Whoosh's is the first negative comment that I have seen.

Dudley

smile boat owners rarely knock their own boats

But one double ender he designed was a full 12 inches down on her marks, enough said the man can not defend himself
beats me why anyone would want a Roberts, so heavy, As Farr once said, light is not weak, and you get their in light airs, takes a flaming gale to move a roberts and why build 65 footer that is up of 40 tonnes when 28 in achievable? Displacement costs, bigger this that and everything else
hey lets start looking after the buyers and stop being so polite, after all you put your plans up for sale RIGHT!!
So why can not anybody critique the design?
I have 3 Holden cars, they are absolute junk, noboby will tell me off for saying so
You take the boat I think I posted pic here, it has been described as a beautiful boat, but I built her and she is not perfect, a wee too full aft which makes life a bit uncomfortable in quartering sea, that and the fact that I should have used aft lowers and no runners

but make some observation in here, no matter how well founded and it is I BEG YOUR PARDON!!
i say Dudley did you ever see a Ganley, or sail upon one?because if you did not, and I suspect you actually have never seen one, then, how prey can you make such a judgement?
Rank Ganley as a real amatuer who scratched a living, from those who misguididly tried save a few bucks on a design

[Welder4956]

I have erred away from aluminum for several reasons;

It work hardens
More prone to stress cracking
Higher distortion rate due to heat co-efficients
Welding requirements demand tighter controls
Electrolysis once complete
Stainless fittings to Ali=not good.
Ease of repair in any port in the world

Have heard the saying from many a sea dog that "steel is real".

Hey if you can disparage those findings with something then i am all ears...well eyes in this case.

I am researching corten (excuse spelling if it is wrong) but am not sold on the benefits as stands. Welding with Lo-hy is no problem it is my bread and butter. But high tensile normally has to give somewhere to gain in another. Jury is still out on that one. Many papers to read still.

I appreciate the input of the gentlemen that have taken the time to help me with this stage of the project. I find politeness keeps the thread respectable and i thank you all for your polite frankness.

I shall be giving all the designers i have looked at as hopefuls their own crack at the whip. Cost is a big deterrent fro the Van de stadt @ NZ$22500. compared with others down at NZ$1500.

[whoosh]

youa re so way off track, but wont go there in here,
Corten, marvellous stuff, compared with the rotton mild steel , which can disappaer in a poof!! if left unpainted
lets talk away from here, send you mail and KI will write or phone
see the boat photo I posted here? well praised wherever she went, but in here? pettiness at work, no comment
Give ALAN MUMMERY a call, a very good NZ designer, many many successful designs, inc ICE FIRE racer

[Fanie]

We all have dreams of creating this very pleasant environment where our kids will visit us and they will be interested in what we have and share our passions.

When they grow up they will have other interests, make their own lives, husbands, wives, kids. If you're lucky, very small chance, maybe one will have a shared interest in your boat, but it's a long shot. It's the way it is.

Our likings in females, cars, places and boats (amongst other things) vary greatly. When you are going to build your boat or have it build it mustn't be what others are going to like - it must be what you like, since you will have to live with it.

One other thing to consider. Today you are young enough to handle heavy stuff, and do everything yourself. If you plan to be in this life still in 10, 20, 100 years from now you have to be able to do what you have to on your boat. So what I'm saying is it should be easy to live in, comfortable, easy to maintain. There will only be you.

Stuff gets old as do boats. By the time your kids are growed up chances are good your boat will be old too, newer and better boats have come along... have more to offer, have more value. You get the idea. Grave yards I mean boat yards are full of pariental good intentions.




Build the boat for yourself to enjoy, it is that value you get out of the boat what counts, and not what it's worth in money. Money is just the means to get something, otherwise it's really worthless, I've never seen anyone enjoy the money, only the things you exchange it for.

Boats are great, aren't they :D

[Wynand N]

Corten, marvellous stuff, compared with the rotton mild steel , which can disappaer in a poof!! if left unpainted


Over rated in my view for the money one pays for it if to be used for building sailing craft. A little more stiff due to the extra tensile and that again makes it harder to shape and welding need to be AWS 7018 LH (low hydrogen) and that calls for a DC welding machine with enough OCV - welding also much harder to master and that puts it out of scope for the majority of amateur builders.

As for the poof!! part, that is the very reason one has to shot blast a steel hull, regardless of the steel used, and to apply a proper compatible epoxy system well within overcoat times.
Steel form rust many times it's thickness and to have the sea eat through it needs a very very long time (years) if the epoxy was damaged and not repaired soon after spotting a chip or damage - and this is true to any material used, fix as soon as damage is observed, period .
The same will happens to you marvelous Corten if the paint is not repaired after damage - people believe Corten is rust proof with some anti-fouling properties due to the copper content of it, please come back to planet earth, that amount is so small, it can be ignored...

Some quotes from Corten spec sheets attached;

It has a higher manganese content to improve its structural properties, but a slight reduction in the corrosion inhibiting elements

Normally the use of unpainted Cor-ten is not recommended for application subjected to salt spray...

Paint does last longer on Corten steel as described in the Painting heading on the specs sheets, but, with damage paint the Corten will deteriorate slightly faster than Carbon steel...;)

[whoosh]

wyn, be honest, ddi you EVER USE corten, and if you did not how can you judge?
main prob plate is , they dont come in larger sizes

[Wynand N]

Yeez whoosh, what is you problem with everyone that differs from you:?:

As a matter of fact I did my first boat professionally, a v/d Stadt 34 with Corten on the insistence of the client. That was against my advise to him and the fact that the plans called for 4mm and the thinnest Corten in my country is 4.5mm - and that added a few good kilos to that hull.

Further more, I spent a lot of time in the mining industry, remember I am a fully qualified boilermaker, before moving over to become as a pro boatbuilder.
The goldmining industry in SA where I worked used Corten exclusively for all the underground equipment such as hopper chutes, hoppers (rolling stock), skips etc. because they were sold on the idea it is harder and resists rust. Ever been in a deep goldmine to see how wet is really is down there?
Best part, many times we had urgent repairs to the equipment, and no Corten in stock, and we use mildsteel to get production back on line, and in fact, no difference in rust resistance could be seen between the two steels.
Rocklast steel, and Bennox outclass Corten under extreme and abusive conditions....

Perhaps my 17 years working with Corten is not enough to raise my views about it in whoosh's view....

[Dudley Dix]

but make some observation in here, no matter how well founded and it is I BEG YOUR PARDON!!
i say Dudley did you ever see a Ganley, or sail upon one?because if you did not, and I suspect you actually have never seen one, then, how prey can you make such a judgement?
Rank Ganley as a real amatuer who scratched a living, from those who misguididly tried save a few bucks on a design

Whoosh, what have I done to you that you feel the need to antagonise me? You seem to have a problem with anyone who has an opinion different from yours.

Yes, I have seen Ganley designs. No, I have not sailed on one. I have known owners and every one of them was happy with his boat. Most of the owners whom I met were passing through Cape Town on circum-navigations. Those who were unhappy with their boats would have stayed closer to home.

[Welder4956]

Does anybody else feel that Ali would be a better option than steel?

I have no problem being able to work Ali although i will have to brush up on my MIG/MAGS skills as i have mostly TIG/TAGS welded Ali.

I am probably from the same school as yourself wynand in that i started as a boilermaker and have been down mines and worked with similar materials. This is why i wasn't convinced with Corten. There are similar metals i have dealt with in oil industry as well which didn't take too well to being formed and became expensive because of this. Also as you say you are restricted by what the mill produces and some of it comes to NZ in odd ball sizes. Most of the local steel suppliers for the quantity needed will need to get it in from Singapore or the likes.

I have noticed a lot of designs are now in Ali and am wondering if my initial thought were far off track. There are far more Ali designs available and a couple of designers have questioned why i would be using steel if i can work in either material. I seems most steel designs can be made from either material.

At least i know what i want it to look like now.

[welder/fitter]

Though Corten was not the "miracle metal" that it was supposed to be, it is only one in a spectrum of HSLAs available. Having said this, I don't believe that the higher dollar investment in building with any HSLA would pay for itself, over the costs associated with building in mild steel, whether for the professional or amateur builder.

Aluminum - LOL, that age-old argument that you find on every boat building and/or design forum! I've seen some nice boats built with Al. From a steelworker's perspective, Al is expensive, as is the weld equipment & a pain in the butt to work with. I've come up with a few concepts for repairing steel marine vessels that have been damaged at sea, but aluminum? Based on my own experiences, I'd want to x-ray all structural welds on an Al boat that I was buying or building. Still, there are some beautiful examples out there for the well-heeled owner.

$22,000 sounds like a ridiculous price for plans for a boat, unless you are a government, then its cheap. However, you are buying a name; more important for the professional builder than the amateur.

Bruce Roberts - I've seen a few very nice boats built from his designs & have seen many & worked on a couple that were garbage. I believe that the chief problem is that more of his boat designs are bought by first-time builders than that of other designers. Yeah, the spray class is overweight & has poor seakeeping abilities, yet, so was the boat that they are fashioned after.

my 2c
Mike

[Dudley Dix]

Does anybody else feel that Ali would be a better option than steel?

For amateurs I would always recommend steel ahead of aluminium. If they choose aluminium then they had better first invest a lot of time in training themselves in the proper preparation for and welding of aluminium. If not then they are at serious risk of a calamity at sea from failing welds.

For a professional, with the ability to work and weld aluminium properly, I have no hesitation in recommending aluminium ahead of steel. The boat must, of course, be built with compatible marine alloys. Aside from the preparation and welding issues, it is easier to work with than steel. The lighter material is less demanding of lifting equipment and can be cut with woodworking tools. It is much quieter to work as well.

Yes, the material and equipment cost more. Overall, it will add about 10% to the cost of the boat but resale value will increase by considerably more than 10%. If you leave the skin unpainted above the bootstripe then much of the fairing and painting cost will be saved to partially offset the increased material cost.

Yes, steel can have a welded repair done in most out of the way places around the world, not so with aluminium. That does not mean that aluminium cannot be repaired in an emergency. The same way that a plywood boat can be very quickly repaired with a few pieces of plywood, some screws and underwater grade epoxy, so can an aluminium boat be repaired with the same materials; or replace the plywood with thin aluminium plate.

An added benefit is improved performance. That means faster passage times and improved ability to sail away from dangers at sea, such as extreme weather conditions.

For myself, I would take aluminium ahead of steel.

[whoosh]

to DD, i HAVE SENT YOU A PM, AND BELieVE ME i AM NOT TRYING WIND YOU UP SORRY, IF YOU SCROLL UP THE thread you will see I recommend you ahead of the other names that came up

to Wynand please dont read more into the posts than you do

i get rather tired of people making FACTS fom the fiction in their minds

On a recent trip to Netherlands, I saw a high speed tender built from Corten, they had to do it that way because mild steel was not strong enough for this service without going for really heavy plate.
i once was asked to roll some transom cnrs for a superyacht, they were only 500 deep as it was for a platform, , my 5 inch rolls would not budge the 6pl, so I had to form those bits in the wheels. the big downside of the metal is that it pulls like mad, bit same as ss that way

I guess I get peeved of people who guess, I can tell they actually are quoting heresay, not from experience
unfortunately I can not tell you in here abt a design name that came up suffice to say there was some legal stuff involved(not me) but was asked to advise
it could well be that you are supersensitive?, but until I talk to you, then please there is no need to interfere is there?
Reply to DD,
I found it took five years to get a welder really up to it, even if he had an ASME 9 or soem other high fallutin ticket, welding is a thankless task, after a day sticking in one whole roll, I would be quite ill

I posted thsi in its own thread a week ago, not one reply, ddi it shock some?

when I was very young there was a man who boarded with us- My dad and I were building a BARTENDER, from ply with massive chines, stem and stern members
Anyways this bloke said you "should be able to belt a hull with a 20lb sledge and it should be able to stay intact"
Years later I read of a boat sunk by orca, she was oaken planked 1 1/4 inch with close spaced oaken frames and floors, she sank in seconds, the book ,Survive The Savage Sea
later again I became a long time builder of metal yachts , oNce I stood on a plank and belted as hard as I could with that hammer a reluctant seam on a tight U forefoot, I was thrown off the plank, only gradually did I move the 5/16 , 8mm plate
I read abt the fleet of steel 65 footers going round ( the wrong way) and how every one of then tinn canned the forefoot area, either too lightly plated, soft plate of too wide frame spacing or all 3
To me having been at sea in tugs, and also sailed such stormy seas as the Tasman, it seems that the sledge hammer test is a good and sensible one
I saw a bloke launch a cat here, he told me he was going to Fiji, 3/8 ply, a mere flick of a sleeping mammal tail would sink that boat, but I just said to him, nice job
YET how many boats could take the hammer test?
When I,m surfing down a wave at night I like to think I,m safe
Greens perhaps the most successful of carbon fibre builders ever, where made to build a section of hull that would be used in such testing for the new boat Shamon, an iron weight was swung at the piece, I am not sure of the weight but it was pointy!!
Greens have had great success with carbon, their round world racers such as Innovation,kaverner surviving totally intact
what do you reckon, can your new boat comply?
And here I think I mean for offshore capable craft

[Wynand N]

to Wynand please dont read more into the posts than you do....
i get rather tired of people making FACTS fom the fiction in their minds...


Looks like you are a one track minded individual - always your way:o Making facts from fiction:?: If you open your eyes and mind you will see that the quotes I made from your miracle plate are taken from the attached specification sheets and that is a fact.

I think you are the fictitious one around here, sitting behind a computer and trying to discredit people for whatever reason you have that mystifies my mind.

I guess I get peeved of people who guess, I can tell they actually are quoting heresay, not from experience

Then again your are also clairvoyant:?: I was raised on the assumption that until proven guilty or has to assume innocence.
Until you can prove me or any other person wrong, keep your mouth shut and be constructive in your comments.

I am a boilermaker for the last 31 years and any b/m for that length of time would have "bumped" into Corten, and unfortunately, I had spent 17 years in the mining industry that mostly work with that crap.
Welder4956 echo's my sentiments on this and funny enough, he has the same qualifications and background as I...

unfortunately I can not tell you in here abt a design name that came up suffice to say there was some legal stuff involved(not me) but was asked to advise it could well be that you are supersensitive?, but until I talk to you, then please there is no need to interfere is there

Some wild statement, but since you thrown a stone in the bush.... Unfortunately, when you build boats, or is in business in any other discipline, you are bound to run into legal proceedings - I had my share of that and I had a well known designer giving evidence for the state that in fact favored me based on the work done in that case. If you care to go to my website, you will see that I mentioned that somewhere for the world to see.
Everyone has his highs and lows and I am not different than anyone else.
I have nothing to prove to you or anyone for that matter and please do not threatens me and no, Im not sensitive in any way.

As for the statement not to interfere - who the heck are you:?: This is a public forum and I can place my replies where and whenever I can as long as it is well within the spirit of the conditions of this forum, and I would advise you to read those terms and conditions as I believe you had not done so by your remarks in some posts.

For more than 4 years I am a member here and I always tried to be constructive in my views and advise based on my hands on experience as a boatbuilder. Usually where I can I back my views with photos or spec sheets (which you incidentally choose to ignore)

If I may, your public profile do not impress me one bit, and I am of the believe that you are a cyber armchair sailor/hopeful boatbuilder antagonizing others in the know as can be deducted from this thread.
My challenge to you now since you tried to shut me down; do not hide behind a username (I use my real name), who are you, show your face (Im not shy of mine) so people can see. Show us some of your work (I do that regularly and my website available to all)

As a parting note: We regularly rolled 12mm Corten into conical sections at the mines, either by plate rolls and if the diameter was to small for the plate rolls, pressed the conical sections by press brake. Your statement in the previous post about rolling 6mm Corten just don't add up. The plate rolls should rolled the plate easier than the wheels and I assume you referring to the English wheel.

If whoosh or who ever he is continue to try and discredit me or anyone else, he will be a one man gospel choir as I said my piece. Everyone knows the saying about arguing with a fool.....

As to the starter of this thread, I apologize for this reply and the fact that this tread had moved away from its intended purpose, but it is obvious who distracted it.

[whoosh]

oh shurrap wyn you are talkin to an old friend

[Dudley Dix]

when I was very young there was a man who boarded with us- My dad and I were building a BARTENDER, from ply with massive chines, stem and stern members
Anyways this bloke said you "should be able to belt a hull with a 20lb sledge and it should be able to stay intact"
Years later I read of a boat sunk by orca, she was oaken planked 1 1/4 inch with close spaced oaken frames and floors, she sank in seconds, the book ,Survive The Savage Sea
later again I became a long time builder of metal yachts , oNce I stood on a plank and belted as hard as I could with that hammer a reluctant seam on a tight U forefoot, I was thrown off the plank, only gradually did I move the 5/16 , 8mm plate
I read abt the fleet of steel 65 footers going round ( the wrong way) and how every one of then tinn canned the forefoot area, either too lightly plated, soft plate of too wide frame spacing or all 3
To me having been at sea in tugs, and also sailed such stormy seas as the Tasman, it seems that the sledge hammer test is a good and sensible one
I saw a bloke launch a cat here, he told me he was going to Fiji, 3/8 ply, a mere flick of a sleeping mammal tail would sink that boat, but I just said to him, nice job
YET how many boats could take the hammer test?
When I,m surfing down a wave at night I like to think I,m safe
Greens perhaps the most successful of carbon fibre builders ever, where made to build a section of hull that would be used in such testing for the new boat Shamon, an iron weight was swung at the piece, I am not sure of the weight but it was pointy!!
Greens have had great success with carbon, their round world racers such as Innovation,kaverner surviving totally intact
what do you reckon, can your new boat comply?
And here I think I mean for offshore capable craft

Wynand has pretty much had the same thoughts about most of the post from which the quote is extracted. I will not say it again. Please see my response to your PM.

Whoosh, you have done a 180 degree turn-around. Early in this thread you favoured lightweight modern boats for offshore sailing. Here you argue in favour of heavy displacement and massive strength.

There is validity in all materials and all types of boats, each in its own place.

You are right, the steel 65 footers sailing the wrong way round the world did suffer oil canning. That is a special situation; who aside from a masochist will circum-navigate against wind and sea except to prove something? Those boats stood up to incredible punishment and did not break, they were slightly bent. Such voyaging is out of the ordinary and needs special design.

Whales are not the only dangers at sea. Boats must also be capable of sailing out of dangerous situations. A catamaran that is heavy cannot do so. Boats have more chance of running aground than hitting whales. The plywood cat that you describe would not be able to sail out of its own way nor beat out of a wet paper bag if built from steel. That would put it in serious danger if on a lee shore in a bay when bad weather arrives. It would also be at risk of being driven under by large waves in storm conditions. It is a safer boat for being lightly built. Yes, it could have been built stronger with carbon sandwich but that is beyond the ability and budget of most amateurs.

It is up to every skipper to sail within the capabilities of his boat. In the past even racing sailors sailed to hold the boat together, knowing that breaking the boat would prevent them finishing. Modern distance racing displays the opposite attitude. Boats are sailed at maximum speed almost irrespective of sea and weather conditions and it is only after they break that care is taken to hold them together. You are not going to find that mindset among cruising sailors. They are far less likely to break their boats.

Dudley

[DGreenwood]

I don't know Whoosh...I tired of responding to this sort of talk along time ago. I am going jump in here, not because I think your mind is going to be changed about anything, but because there are others that are trying to decide who to hire to help them.
Either you are not as experienced as you say, or you have not payed attention all these years.
Boats are not boats. They vary in function and appearance as much as land vehicles. You seem to classify all of them, and test their worth with a few simplistic swings of the sledge.
In fact I will use land vehicles to show you how silly you sound.
Here, for example is a vehicle I might test with your sledge hammer. The bed needs to be able to repeatedly take the blows of 300 tons of rock on a daily basis...
28334

Here is one where you would likely find the your sledge test would be pretty worthless...
28336

As to your complaints about steel boats faltering when subjected to an extremely harsh environment in a race that is designed to test the human spirit and really verges on the absurd, take a look at this. I think it is just awful that these school buses can't make it around the race course any faster than they do without breaking down. What a poor design!
28338


As to your harangue that building right side up is the only way to go is as naive as it gets. Whether or not you choose this is dependent on many things besides personal taste. The material and method you are building with, the nature of the build floor, the availability of turning equipment, the size of the boat, the overhead room in the structure, just to name a few considerations. Many, many companies that I have seen and worked with, that have some really bright fellas working in them, have chosen methods that differ from your "only way".

I suggest you step back a little and listen to some of the experience here. You have not found the way yet "Grasshopper":)

[Dudley Dix]

I would like to pass on some information to the forum about whoosh. He has now told me his real name so I have been able to check back in my email files to find what was said.

You can read earlier in this thread how he said that he had contacted me and found me inflexible about my boats having to be built upside down. My emails to him in 2003 show that I told him exactly the same as I did on this forum. It is not up to me to dictate to builders what methods they use. I am flexible on most things. For some reason this man would like the boatbuilding world to think otherwise.

In 2003 he approached me and proposed that he write material for me to post on my website promoting and advising on building round bilge designs instead of multi-chine and radius chine hulls. Within 2 emails I could see that there was no room for us to work together. I told him that his ideas and mine were too far removed from each other so I declined his offer. In retrospect that was a very good decision.

He is posting under the name of "whoosh" but anyone interested can read many other posts by him under the name of "Lazeyjack". Of particular interest is the thread that he started about rudders on one of my cruising designs. I was not aware of this discussion until this weekend, or I would have posted a response. You can read the thread at http://www.boatdesign.net/forums/boat-design/comment-rudder-24258.html .

I am not so naive as to think that I am one of the best designers in the world but I am confident that there are not 10,000 better designers as he would like you to think. I doubt that there are 10,000 designers in the world, so that would put me at the back of the pack. Bear in mind that his opinion is tainted somewhat by me rejecting his offer to help me.

This man represents exactly the reason why I am very seldom found in the boatbuilding forums. It is not possible to conduct a reasonable discussion with such a person. They are very opinionated and will not accept contrary thoughts. They give inapropriate advice while insisting that they know everything about the subject. On top of that they are often abusive and destructive and they generally do so under a pseudonym. They can snipe annonymously at those of us who are posting under our own names.

The danger is that they do appear to be very knowledgeable to the newbie, who can be easily led off in the wrong direction. Taking the advice of someone like this is really no better than acting on the advice of an armchair sailor at the local yacht club bar.

The internet is a great resource for finding info on any subject that we can think of. The difficulty comes in sorting the good info from the bad. I am sure that this man has a lot of useful advice for visitors to the forum, if only he would be reasonable and balanced about how he offers it.

[Ilan Voyager]

Mr Dudley Dix: I've always appreciated your designs for their rationality and search of simplicity. Your plans have excellent reputation for their quality, accuracy and precision of details.

Mr Wynand N: I've spent enough years in shipbuilding to see immediately in the pictures the quality of your work. The clients who give you a boat to build are lucky guys.

I agree with you that good plans like those from Van de Stadt are worth their price, as that eliminate further "shitty" engineering and wild guesses which can end in very expensive mistakes. The price of plans from a good NA is a very small fraction of the total price of a boat.

Sirs, do not waste your time with such people as Lazeyjack / whoosh. Simply do not answer, ignore them.

[LyndonJ]

For amateurs I would always recommend steel ahead of aluminium. If they choose aluminium then they had better first invest a lot of time in training themselves in the proper preparation for and welding of aluminium. If not then they are at serious risk of a calamity at sea from failing welds...............

Bridges we were told are a very good analogy to boats when you think of structural materials and the results of failure. Lots of parallels-- usage-- loading --failure modes --materials--areas of operation-- user expectaions, the lecture got hillarious when we started talking about high -performance racing bridges but he was making a point.

If you want to build a boat that will be used by your great grand kids generation then there is only one material that is the real gift from God :) Weldable with 100% strength means heaps structurally.

We had some detailed lectures and a string of slides showing some very serious failures of alloy boats professionally built after extended periods of heavy weather. I think the enginers may not be as keen on this material as they are of steel for a host of reasons.

In the very educational 84 Sydney-Hobart 106 boats out of 151 were forced to retire. Out of the entire fleet alloy boats made up 14% of the hull construction material but these boats had 21% of the structural failures forcing retirement. They were second only to the Kevlar-carbon -fibre boats for structural failures attributed to their construction material.
Steel boats had zero structural failure and GRP faired significantly better than alloy, even foam cored GRP was tougher than alloy.:rolleyes:
This lead to at least one insurance company putting up premiums for alloy boats.

Load cyclres in the weld zones is often the cause, but also plain outright strength where a lightly built steel boat might buckle a panel the alloy boat often splits a weld as well as buckling the panel, When one weld fails that can cause another to fail and so-on in prolonged heavy weather this can be very serious in a non -compartmentalised boat. In some commercial craft the bulkheads split away from the frames they were welded to as the boat wracked.

Resale prices for old used aluminium boats seem to be lower than their steel counterparts, brokers have had real trouble shifting older used alloy boats, becasue the surveyors are not kind to old alloy boats. Alloy also forms those ugly oxide scabs and little pits everywhere the salt water has been when it is unpainted. In warm salt water environments alloy boats are probably more corrosion prone than any other material unless well painted inside. outside, in tanks, stern tubes the lot. If the paint is breached the corrosion gallops underneath lifting it off in all directions and corroding with unleashed energy.

Alloy has not been very succesfull in the offshore blue water fishing fleet that operates in Southern waters and these boats are migrating back to steel, even some new boats have split long welds in bottom panels after only one season.
Some boats even have had to be re-welded extensively after delivery trips that met heavy weather.

Lazyjack said steel disappears...Poof ...but this is crap, it has a very slow and very obvious corrosion. Its Aluminium that can corrode fighteningly quickly given the opportunity, it is very high on the energy scale close to magnesium. It's only the surface oxide coating that stops it oxidising instantly in air and turning into a pile of powder. Just to give an idea of how reactive it is, In a high pressure pure oxygen environment if you scartch it with a piece of steel it ignites. I know this is irreleveant to boats but in the right circumstances Alloy really does go "Poof" or "Whoosh" and dissapears into a pile of powder.

[goboatingnow]

Its interesting that a recent video put out by Cunard on the building of the QM2 , stated that besides from cost one of the main reasons was that the deck and super structure of its predecessor the QE2 was constructed from aluminium and now required signifcant remedial work. The QM2 was completely constructed in steel.

[Ilan Voyager]

What a dark picture of aluminium...That almost make you believe that a number of NA and Naval Engineers are poor fools using that material. There are very good and long lasting boats in aluminium: the Pen Duick III (1966), the Pen Duick V (around 1971), Pen Duick VI (1972) are sailing today with no problems, a lot of fast catamaran ferries (Juan Patricio: 60 knots every day in the Mar de Plata, and many others), a big number of fast patrol boats in numerous Navies, plus dozens of fishing boats (the older I know has 30 years), yachts, pilot boats etc. Add all the super-structures of cruising boats in the Caraibes (a lot made in Finland) brief many, many boats using aluminium without special problems.

As always with any material it needs good engineering and craftsmanship and in the case of aluminium the good alloy. You will find in any material bad records of poorly designed and/or badly built boats that crack, split, and even sink.

About the QM2, the main reason was cost and nothing more.

[Ad Hoc]

Welder4956

Firstly I should point out that if you try and weld and fabricate aluminium the same way you do a steel structure, you’ll make a pigs ear of it. The two are chalk and cheese. Steel being bash bash bash all is ok, whereas as ally is to be treated with kid gloves. It is like comparing a formula 1 racing car to a day to day saloon car.

1) Work hardens. This only occurs during manufacture, not welding. The work hardening is simply using mechanical means, by the use of slip planes within the alloy to dislocate and move the crystalline structure closer together. In other words it makes the movement of the crystal matrix under strain more difficult, thus increasing the properties. An “O” temper for example has minimal work hardening and as such is easy to fabricate, roll, bend etc. This is reflected in its “yield” strength of around 120/5MPa. Whereas “H2” temper for example, is heavily strain hardened. As such is much more difficult to bend and fabricate under the same conditions as O-temper, has a “yield” of around 240MPa. Only when you weld H2 temper, locally, will it revert back to O temper.

2) Yes it does distort more. This is where one must exercise caution and balance the welding. However you can weld 2 identical structures under same conditions and each will distort slightly differently. Good practice and procedures minimise this to be just a minor inconvenience.

3) Welding controls. This is really down to the skill of the welder, if I understand what you are saying correctly. Not everyone can weld ally very well, it is an acquired skill. Also, the new range of sets such as those from Fronius are serious sophisticated, these help lots too.

4) Electrolysis. This only occurs if there bimetallic corrosion can take place. Such as bare copper pipes allowed to drip condensation onto the plate etc. This is generally poor design or incorrect procedures during production.

5) Stainless fittings. If they are high quality stainless, and the fittings are not constantly being scratched, there should not be a problem. I’ve used SS fitting for many years on ally, with no serious problems. Usually basic maintenance will prevent any occurrence of corrosion. SS has a tough oxide layer, rather like Ally.

6) I’ve been all over the world overseeing repairs. Oddly enough the worse place I ever came across for getting qualified coded welders was in Barcelona. Had to train up 2 local guys to assist on a job. However if you are talking about actual repair of the job...again, this is a specialised skill. Being a good ally welder in shipyard is not the same as being a good ally welder on repairs in ports or elsewhere. Not everyone can do it.

Maybe this will give you some thoughts?

As for Cor-ten, it has better corrosion performance compared to other high-strength steels. However, when left unprotected it rusts uniformly until the action stops after 1~2 years. After which no maintenance is required. It is slightly more nobel than mild steel so being slightly better protected underwater. For example, if the shaft is a low alloy steel on a mild steel boat, the difference in potential is not enough to prevent rusting though. Its prime attraction is slightly higher strength and a lower rate of rusting, but of course at a cost…so is it really worth it. Better to put the money into blast cleaning and epoxy painting.

[Welder4956]

Gentlemen,

It has been a little while since i last thanked you for your valuable input and offered some insight into how my quest is going.

I recived my study plans from a handful of designers and have looked long and hard at these.

From talking to various individuals and reading material we have shortened the the length of the vessel and lightened it by going with Aluminum.

I am now getting my suppliers to give me quotes on materials and profile cutting services.

I must add that the VDS study pack was exceptional and was most insightful. compared with a couple of the other i received which were paled somewhat in comparison. Not to say there were not sufficient information but when placed next to the VDS set well....the bar was set high by these gentlemen.

Now that i have reduced the size of the vessel it has opened up a couple of designers that i could not use for the larger size so i will need to look more at the available shapes and configurations.

My welding plant has been ordered for the end of the month and once i get plans and material should be looking to start construction August.

But as they say anything could happen in the next half hour.

[whoosh]

congrats my boy!! a wise decision, and VDS always sell well Mico Metals have keen prices and branch in your town
Always get you mill cert. and keep the cert numbers against where you place the plate on the boat
Will follow with interest
to those who posted strange things of myself, I start to put my gallery together

[Wynand N]

I must add that the VDS study pack was exceptional and was most insightful. compared with a couple of the other i received which were paled somewhat in comparison. Not to say there were not sufficient information but when placed next to the VDS set well....the bar was set high by these gentlemen.


then wait until you get the complete set of plans with booklet and literature that goes with it - you even get a metal plague with your design number (making your plans legitimate) and other data left open such as builder, date etc. This you can mount at a convenient place in the boat. I usually mounted the plague at the nav station...

I said it before - vd Stadt is my favorite plans to work from:cool:

[Ilan Voyager]

I agree totally with you, Wynand.

Van de Stadt is Dutch high quality: that means all...Some of my acquaintances built VDS boats with always the same results; very good boats, cleverly engineered, built by the simplest ways with so outstanding plans that you want to put them under glass in your living room. It's money well spent.

For those interested I give some links;

http://www.stadtdesign.com/
Two methods of boat building used by VDS
wood core
http://www.stadtdesign.com/English/history1.htm
quick assembly steel or alloy
http://www.stadtdesign.com/English/history11.htm
Very good method for metal boats. Fast and simple. I have used a similar method for patrol and fishing boats. A similar method can be used with polyester boats.

A digression: when it's possible the use of good prepainted steel plates saves a lot of money of sand blasting and finishing. In France I've used prepainted Marinor (a steel with exceptionally easiness to form and weld). It's worth the extra cost of material because you save more while finishing the boat.

Out of this thread but interesting;
http://www.stadtdesign.com/products/SwingRigInfo.html
http://www.swingrig.nl/ (in dutch)
http://www.boatdesign.net/forums/sailboats/swing-rig-whats-all-about-6493.html

About the freestanding mast promoted by VDS.

[whoosh]

AD HOC

If you have to bash bash bash either, you are doing something very wrong, you should be able to stretch and form so that the plates fit with no struggle at all Good steel building requires I would say more skill, even though I build in. The welding requires more skill
I have no idea where you got the idea alloy distorts more than steel, it is in fact quite the opposite, the reason being it soaks up heat faster
having built many of both and 32 aluminium vessels myself, I assure you this is not the case.

[whoosh]

What a dark picture of aluminium...That almost make you believe that a number of NA and Naval Engineers are poor fools using that material. There are very good and long lasting boats in aluminium: the Pen Duick III (1966), the Pen Duick V (around 1971), Pen Duick VI (1972) are sailing today with no problems, a lot of fast catamaran ferries (Juan Patricio: 60 knots every day in the Mar de Plata, and many others), a big number of fast patrol boats in numerous Navies, plus dozens of fishing boats (the older I know has 30 years), yachts, pilot boats etc. Add all the super-structures of cruising boats in the Caraibes (a lot made in Finland) brief many, many boats using aluminium without special problems.

As always with any material it needs good engineering and craftsmanship and in the case of aluminium the good alloy. You will find in any material bad records of poorly designed and/or badly built boats that crack, split, and even sink.

About the QM2, the main reason was cost and nothing more.
you have to remember Island voyager that ALL the knockers of al al, have never used it
I wonder why the worlds billionairs get their vessels done in Al Al?
I know of one yacht in perfect condition, MORAG MHOR, built 1959 in UK saw here in St Maartin not so long ago

[Ad Hoc]

Whoosh
Well, clearly you have been using a very different form aluminium than everyone else when welding boats together.

The coefficient of linear expansion of aluminium is 24 x10-6 C-1
for steel it is 11 x 10-6 C-1

In other words aluminium expands more than twice than of steel in one direction.

When talking about thermal expansion, ie volumetric, the ratio is still approx 2:1, that being 69 x10-6/K to 32 x10-6/K.

So when you heat up aluminium, the heat travels faster and the alloy expands and moves to accommodate the increase in volume owing to the heat much more than steel.

As for the bash bash comment, you clearly didn't read the whole text and its meaning.

[whoosh]

Whoosh
Well, clearly you have been using a very different form aluminium than everyone else when welding boats together.

The coefficient of linear expansion of aluminium is 24 x10-6 C-1
for steel it is 11 x 10-6 C-1

In other words aluminium expands more than twice than of steel in one direction.

When talking about thermal expansion, ie volumetric, the ratio is still approx 2:1, that being 69 x10-6/K to 32 x10-6/K.

So when you heat up aluminium, the heat travels faster and the alloy expands and moves to accommodate the increase in volume owing to the heat much more than steel.

As for the bash bash comment, you clearly didn't read the whole text and its meaning.

to dix
the boat here nimbus 2 has a below wl pl of 8mm, that is equiv of 2.5mm steel so strong is not necessarily heavy
the weight of this 54 footer 19tonne at departure
to ad hoc, can you post what YOU HAVE BUILT, i SEE NOTHING, in your gallery
I know Wnyard is real, but as for some of you that have knocked me?
ad hoc, you are totally and absolutely wrong to demonstrate simply lay 2 plates on ground make a 12 foot long butt, in steel without peining first, in 4mm plate, watch the spagetti mess you arrive at
now take two alloy and do same, backstepping , just the speed alone which is many times faster, in the weld, ensure far less buckling
Until you prove who you are then why should we listen? I have given you positive pts for some of the things you wrote, others like your post on 6061 was totally wrong
I can tell by the way you write, yours is a paper theory, lets see what you did please and tell me who do you work for and do you have welds tickets?

[Ad Hoc]

Whooosh

So are you saying that aluminium does not have 2 times the coefficient of linear and thermal expansion of steel?

Since you feel you know more than the known laws of physics. Here is one in your "language": so perhaps you may like to read:
http://www.lincolnelectric.com/knowledge/articles/content/feedingaluminum.asp

Simple quote
"..Aluminum expands more than steel as it heats up.."

[whoosh]

Whooosh

So are you saying that aluminium does not have 2 times the coefficient of linear and thermal expansion of steel?

Since you feel you know more than the known laws of physics. Here is one in your "language": so perhaps you may like to read:
http://www.lincolnelectric.com/knowledge/articles/content/feedingaluminum.asp

Simple quote
"..Aluminum expands more than steel as it heats up.."

ad hoc, I notice you have not answered my questions
I no bugger all abt science, all I know is from 35 years HANDS ON is that when youi weld a piece of alloy the area all becomes warm quickly, that is because it conducts heat, therefoire local HOT spots are coolwd evenly and quickly, in realtionship to steel , where you weld and the area around stays cool, the weld is hot, the area that is hot shrinks down, far more than in alloy, so welding flat plates as per a b/h you would either pein the seam area first or after
Are you a student, a new grad? because youa re talking like someone who is all theory, , and thsi is NOT meant to insult, its just that I have worked with so many people with bits of paper to their name who quite frankly know zilch
It would be good if you could answer the questions, tell us what YOU have built, and who you have worked for. Put a name to your posts, mine is Stuart

[Ad Hoc]

Whoosh

Clearly you prefer the "mine dog is bigger than you dog" discussion. Since showing pictures of boats does not convey the quality of the fabrication, only that a boat has been built, nor does it convey any understanding.

The position you take that you dispute the fact that aluminium expands and moves more than steel, despite the known laws of physics to the contrary, highlights this point. As such our foundations for a discussion are no longer valid, as your points of reference are diametrically opposite to that which is well established by many independetly.

[whoosh]

Whoosh

Clearly you prefer the "mine dog is bigger than you dog" discussion. Since showing pictures of boats does not convey the quality of the fabrication, only that a boat has been built, nor does it convey any understanding.

The position you take that you dispute the fact that aluminium expands and moves more than steel, despite the known laws of physics to the contrary, highlights this point. As such our foundations for a discussion are no longer valid, as your points of reference are diametrically opposite to that which is well established by many independetly.
well that says it all,
you have not backed your considerable words with any proof, clearly IMO you have just copied stuff from a book, a pic is worth a 100o words. And really what a person has done is what counts, words mean very little
Your profile is empty, you know nothing and it shows, never mind, you are keen perhaps one of us builders may give you work, and teach you to weld, form stretch , and in general build a BOAT, but you really should stop giving bad info as people who know little will believe you
goodbye

[Welder4956]

Trying not to add fuel to the flame but to answer the question posted to me by whoosh.

I have no idea where you got the idea alloy distorts more than steel, it is in fact quite the opposite, the reason being it soaks up heat faster
having built many of both and 32 aluminium vessels myself, I assure you this is not the case.

I have been welding for the past 18 years and i have welded all manner of materials. I have fabricated from a many different items from Exhausts to missile parts and the odd ship or 2. I shall endeavor to explain what i believe through a 5 year craft apprenticeship rather than a university paper.

When you weld a material you create a HAZ(Heat affected zone). Now with steel this remains relatively small because the heat conductivity of the material is lower. This means the steel will distort only about the HAZ thus your comment on hammering and peining. With Alloy the conductivity is far greater and the heat dissipates throughout the entire part (soaks up as you put it). In fact the furthest point will heat faster than the welding area. As this is the case more heat is required to maintain a weld pool and in some cases a pre-heat. The other issue with alloy is that it has 2 melting points in the same plate. That of the Aluminum and that of the Aluminum oxide which forms on the outer 2 microns (about 1/50 of a thou for all you USA types out there) of the plate. Because the core of the material melts at around 800Deg and the oxide at around 1300Deg the core will expand faster than the oxide. This causes the dendrite crystal formation to become restricted and begin to distort the structure of the oxide layer. For material to normalize it is best to cool naturally and return to an equiax crystal formation. I beleive these properties are what leads to work hardening and a lack of elastic property in the material. Try welding up a box made from steel and then the same from ally you will see what i mean.

Now as a famous engineer once said "You canny change the laws of physics captain"

Boffins feel free to add the science bit to that.

Now that was what i remember from 15 years ago studying city and guilds in weld metallurgy. I have not looked in a book. But i can if we need to.

If you recall this was not a thread about welding the boat. It was about which designs to look at. Not arguing with any of you as it is pointless and time consuming. Have asked for quotes on materials from MICO and Ullrich.

Should this thread be later read by someone wishing to know the properties of the materials and their weld ability i would suggest they visit either the TWI web site or www.ukwelder.com both of which are frequented by the best in the industry of welding. Not necessarily people who have only ever welded boats.

Whoosh your input has been thought inspiring to say the least but not always all together correct but not without substance. But without you this thread may have only been 2 pages long and where would the fun in that be:p

[Ad Hoc]

Welder4956

Not bad :)
Only 2 main comments.
The oxide layer must always be buffed off when welding ally, which i'm sure you know...for said reasons as well as inclusions etc.
Secondly
"..For material to normalize it is best to cool naturally and return to an equiax crystal formation. I beleive these properties are what leads to work hardening and a lack of elastic property in the material..."
Work hardening is by mechanical means not by heat. Mills roll the plate which become more and more flat, as well as increasing the mechanical properties. That is why rolling H116 plate for shell plate is so much more difficult than O temper. H116 is work hardened, O-temper is not. (well just minimal for straightness etc). Rolling, bending forming bashing with a hammer etc when fabricating increase the work hardening further. The heat affects the working hardening, ie it releases the 'locked in strain' created by the mechanical process.

[Dudley Dix]

to dix
the boat here nimbus 2 has a below wl pl of 8mm, that is equiv of 2.5mm steel so strong is not necessarily heavy

At no time have I ever said that a boat has to be heavy to be strong. The fact is that steel is strong but it is also heavy. Aluminium is also strong and it is lighter, about 50% of the weight of steel for similar structural stiffness.

[Brent Swain]

You are unlikely to need any patterns if you build from a CNC kit. Most builders of my boats build from offsets and bulkhead/frame diagrams, if building from scratch. A small percentage order Mylar patterns. Only some of our dinghies are built from paper patterns, they are too dimensionally unstable to use for larger boats.



Ganley designed some really nice steel boats. I have a lot of respect for his work. I have only heard good reports of them from owners. Whoosh's is the first negative comment that I have seen.

Dudley

Ganly was that all too rare character, a designer who actually got his hands dirty building his own designs. Thus they go together far more easily than those designed by people who only draw pretty pictures of boats and never actually try to do what they are asking others to do. They are excellent and practical designs, and I've never met an owner who was unhappy with his Ganley. They are designed with steel in mind ,based on steel working experience , taking full advantage of the material, not a copy of wooden boatbuilding .
Brent