Transverse frame calculation

If those drawings posted showed a structual defalt I would agree with you. I fail to see what was amiss there .The one posted before that with the twin keels was a good valed point.
Have you ever seen an origami boat go together ?

 

I've watched some of the videos and read much of the material.

I think I have been very consistent in my opinion, I am a fan of the concept Brent is marketing, but not the substance or his method.

I like the idea of using large monolithic plates so that the hull is well faired with minimal work.

I also agree with Brent that steel is a remarkably strong material.

However, yes.... looking at the minimal drawings I have seen, the drawings lack transverse crossmembers and lacking those, enough cross-sectional rigidity in the skin thickness and in particular the weld zones.

The problem seems to be that Brent is not addressing certain potential failure modes that the forum has addressed.

Brent likes to say that he is applying the same construction techniques used in GRP boats, but in a much stronger material, steel. And says that he is basically building a steel monocoque, but I guess what he doesn't understand is that for a monocoque to work the skin needs to be in tension, and supported internally by a frame element (integrated geometry). (like the multiple layers of steel in the A pillar of a car)

He makes token arguments about how longitudinal frames are sufficient. This is simply not the case, and it has been talked about ad nauseam on this forum so much to the point it isn't even worth mentioning as it has been previously covered.

 

Mike,
great post! I have followed the discussions about Origami boats on this and several other forums for some time now. Just as you I found Brent Swains propaganda attractive for a while. With no professional technical background it took me some time to understand the reason for the often heated discussions.
A while ago I bought the "plans" for BS’s 36 footer, mostly out of curiosity. At arrival the poor details of these design sketches and the almost complete lack of technical data came as no surprise. I have bought some study plans containing more information!
Back in post # 51 in this thread I asked for technical explanations about what was wrong with BS designs instead of statements about that they are insufficient. This thread has been priceless! My sincere thanks to Mike Johns, AdHoc, LyndonJ and everybody else who put considerable time and effort in as thorough an explanation as can be made given the complete lack of information of technical details provided by BS himself.
This discussion has made perfectly clear that BS neither has the technical knowledge nor the dignity to accept various offers for improving his designs in order to be able to sell his clients a safe product developed to accepted design standards. As on various other occasions on this forum he has again sidestepped any question to technical aspects of his designs and has answered any criticism with rudeness and/or unsubstantiated anecdotes.
For all I care the discussion on this thread has been invaluable. I have no doubt that it has been an eye-opener for many. It should be used as a standard reference every time BS coughs up his mantra on this or any other forum.

Walter

P.S. Brent, by the way: In your post number 96 in this thread http://www.boatdesign.net/forums/metal-boat-building/realistic-scantilings-20941-7.html#post209812 you mentioned the following:
“I have an ultimate stability curve which I'd be happy to post here, but I don't have access to a scanner. My boats have positive righting moment to beyond 170 degrees.”
That was in June 2008. Still haven’t found a scanner yet? I’m sure lots of people would be happy to look at this stability curve. A hint: You can make a scan on most every copy-machine in most every public library.

 

Valid points, thanks.

And thanks Mike (welder) for his comments.


Here we have another promoter of the "unsupported plate" method:

http://www.al-yachtdesign.de/baufotos.htm

but different from Brent, this guy has some technical background and knowledge.
No wonder, his hulls are "unsupported" only in the very first stage of building, then:



then we see what BS calls superfluous, frames and proper longitudinals.

Everybody may interpret that as he likes.

Regards
Richard

 

Great discussion .. thank you all !!

 

Skin First

Skin first and adding all those frames after is an interesting way of doing it, makes my knees and back sore just thinking about it.
I played with the idea on a roberts 31' with the frameless method taken one step farther, skin first in a basket mold did a 1/4 size model. By the time I had it done I came to the conclution why. There didn't seem to be any real time savings vs framed first. I had to mod the bow entry a little, that and I would much prefer to have chine bars for the added strength.
So I opted for the framed first version
Tom

 

1) The "origami" method will not save time in building. I have met people whom have built these boats quickly and those who have slogged out the process for years. The build time is dependant on the builder, not the method of construction. Yes, a builder of the traditional w/transverse frame method might spend an extra 2 to 4 days making frames, but this is not a significant period of time when one considers the time to build a complete boat.

I left one client there with about two weeks welding to do at one point . When I came back months later , not an inch of welding had been put down. That commonly happens with back yard boats which is definitley not the fault of the building method. Those examples are everywhere in al designs. When you have pulled a hull together , it won't grow to completion on it's own if left out in the rain.
What really counts is the total number of man hours it takes to finish the steel work.
Lyle built the Spirit Bear with a gas driven welder as his only power source. By the time the steel work was done, he had a total of 350 hours on the hour meter, counting all welding , fitting , grinding and tacking. You'd come nowhere near to that time saving with a framed hull. You can build a set of frames in a few days. Then there's setting them up, fairing them fitting plates to fit them, four times the number of feet of seam welding, fairing, etc etc.
There is no way I could have built my hull from plate on the ground to launching in less than a month, starting from scratch, with minimal equipment, using anything but origami construction. Tom, keep track of the total number of hours in building your framed hull, and see if it is below 350 hours. Let us know how you make out . Right now you are just speculating, and estimating the time..

2) The scrounging of materials & construction of homemade versions of winches, anchors, etc., would use up any minor gains in time.The use of scrap material is a non-starter with me, due to fatigue life of alloyed metals. The other homemade bits & pieces would save money but lower the resale value and narrow the market of buyers. The anchor is a rip-off of the Danforth design, with subtle changes to disguise this. I don't steal cars from dealerships because I think that they sell them for too much, why would I do this with anchor designs?
Scrounging is sport not work, That is why I never charge for scrapyard time.
I don't trust stainless for any high load areas, just use it for wear strips on high load areas , wrapped in mild steel . My book and drawings make that clear. In that situation, metal fatigue is a non issue, and the price of new stainless is not even remotely justified.
Patents on danforth anchors, and many others , expired decades ago..

3) The lack of commonsense in steel fab/welding aspects of these boats is disappointing. The arrogance of the designer in sticking to his erroneous beliefs is annoying & could lead a first-time builder to make serious mistakes.

The lack of any real innovativeness in the last century of steel boatbuilding, except for rare exceptions, like Van de Stadt, and myself is an abysmal lack of common sense, as is the "Be reasonable and do it the hard and expensive way ." Or "If you don't have a pile of cash, forget about the cruising lifestyle" Attitude.

4) The anomalies ingrained in the design & book are of worthy concern. I place far more value in the opinions of the "detractors" on this thread, as they have much experience & have made reasonable offers to assist Brent with the engineering of his design. Such an offer is a dedication to spend hours that these people would normally be earning a lot of money for. That is gold, not pyrite.

They all have one thing in common, zero experience in cruising offshore in origami boats, and most have zero experience in building one, or in building both ways..

5) If Brent has no personal issues with a builder, he will spend much time on the internet helping them in their build and if they are in the local area(Comox Valley) he will advise in person & will assist if they wish to hire him. Yes, it is a great benefit and not common to have such involvement of the designer.

6) One must have a very thick skin to tolerate Brent's abrasive, and sometimes incorrect, opinion/responses. I couldn't imagine having to be in a designer/builder relationship with such a person for an extended period of time. Fortunately for Brent, many of his builders are first-timers & will follow along like an obedient sheep. Those whom question will normally be bleated down by the flock. In comparison, I have spoken to designers whom answered my questions in a non-confrontational manner, choosing to assist, rather than offend me.

i go put of my way to help steel boatbuilders, and cruisers in general , in trying to answer their questions on this and other sites, and find simple answers to their problems, often at no benefit to myself as my postings on many sites will attest to. I have a low tolerance for those who would discourage them realizing their dreams , in a safe and affordable manner, by advocating only the most tedious and expensive solutions as the only ones which will work. For that I make no apology.
I have been able to drastically reduce the cost of may very expensive items a cruiser requires and have publicized those findings freely, without making any attempt to monopolize the knowledge.

7) Though pertinent info. is missing from the design plans, with the book, video & web-site(origamiboats group), one can collect all needed information. This gathering of information, which should be included in the plans, does take time, however.

8) Twin keels! There are not many steel boat designs that incorporate twin keels and this is an attractive aspect to some, including myself. Unfortunately, the structural support of these keels is questionable.

You have praised that which has proven inadequate in the past, while criticizing that which has proven far stronger. Your judgement is based on speculation, praising that which has already been proven inadequate , not hands on experience.

9) The evolution of Brent's design seems to have gone through stages of improvements over the last few decades, with the kinks being worked out as problems are encountered, rather than through sound engineering principles which could have been instituted at the inception of the design. Once around "the spiral" is not enough, gambling is for Las Vegas, not boats.
All designs should be improved over time , based on the experiences of owners. Al one off first boats have a few lessons to teach us. Even after decades there are new lessons to be learned (Like Toyotas)
Having hundreds of a given design out cruising and the lessons learned incorporated in plans is a huge advantage. A designer who won't admit his initial design could be improved os a designer ot be avoided.
I remember when offsets had to be faired each time. It was the responsibility of the designer to incorporate corrections from the first full sized lofting in the table of offsets. It was rarely done. Any new method of doing anything is a learning curve, unavoidably. No one has ever developed something new which was beyond improvement the first time it is tried. If we insisted on that, nothing new would ever be developed. New clients have the benefit of three decades of experience an development.
Nothing ventured, nothing gained..

10) Brent's design is not the panacea of steel boatbuilding, merely another means to make a boat. By denigrating "the establishment" Brent has developed a reputation as a "Maverick", which can be attractive to someone who has no knowledge of why designers & engineers do what they do & therefore can not comprehend the value of what they are offering. To wit, it doesn't matter if your plans cost $500 or $2,000 , when one considers the total cost of building a boat. If you can't afford the more expensive stock plans, you really can't afford to build a boat. The price is indicative of the time taken to develop plans and in consideration of market value of the plans. Most designers would suffer great financial loss if each set of their stock plans were only sold once or twice. Those plans must represent EVERY aspect of building the intended boat, or the designer's reputation will sink like a rock. That is reality, not rocket science.

Again we hear the elitist rant."Only the rich should be allowed to go cruising. Keep the riffraff under the bridge." Makes an egalitarian guy like me wanna be abrasive to such *******s. Freeing the rifraf give me a huge sense of accomplishment.

11) The bs of building faster, stronger, better by utilizing this method is, to use one of Brent's favoured phrases, "Snake oil salesmanship."
Snake oil - definition:
"A product that has been proven to not live up to the vendor's marketing hype. The term comes from the 1800s in which elixirs and potions of all kinds, even ones that supposedly included the oils from snakes, were sold as a cure for everything that ailed a person."

I had my buddy call someone who was recently selling a Swain boat. Afterward, my friend gave me the notes he had taken, over the phone. The selling points were the same mantra that is found in Brent's various comments, in his book & on the group web-site. In fact, I finished most of my buddy's sentences in that conversation. Had my friend been a serious buyer, as someone who is not overly knowledgeable in steel boat building - though he built a couple of wood sailing dinghies in his earlier years - he told me that he had become somewhat excited by the seller's salesmanship of the design & construction of the boat in question. "Great spin" was his comment. So snake oil salesmanship is contagious.

Someone once commented to me about the huge amount of offshore experience people who seek out my boats often have. Some are on their second or third origami boats after much offshore experience in other boats. I value their opinions far more that that of the arm chair talkers.
if there is a serious structural deficiency in a steel offshore boat it shows itself quickly, and doesn't wait for hundreds of thousands of offshore cruising miles in extreme conditions, before suddenly deciding to show itself .
Many of my boats have sold for many times what their owners have invested in them, not the case as the initial price goes up, Beyond a certain point ,you are lucky to get your initial investment out . The higher the initial cost the narrower the gap, until it becomes a money losing proposition. Rutherford, the original owner of Waterline Yachts, agreed with me on this point.

Brent

 

When will you learn to use the "QUOTE" button,

BS?

 

I hit the quote button. If that is your only remaining problem, I'd say we narrowed it down a bit.

 

How hard is it?

If you had poked it it would look like this.

 

I wont bother repeating the same old tired arguments again, they have been done to death, despite Brent’s constant ignoring them and refusing to answer the questions he himself raises in his anecdotal replies.

However, here is the crux of Brent’s position:

1) His trump card to persuade the novice and poor individual like a rabbit caught in a cars head lights, is that he has more offshore sailing experience and wait for it, in an origami boat.

So, I bet we can take a straw poll and find perhaps only Brent who has BOTH the offshore experience IN an origami boat.

Thus if you have plenty of offshore experience, perhaps more than Brent, he pulls out the….ahhh…you see…but NOT in an origami boat.

The point being…????...but by then the poor person caught in those heads with tails of joy and life changing experiences, has been sold and never questions the messiah.

2) and then...Zero experience in building both ways.

If poor person who is now caught on those head lights and frozen, and is willing to accept all arguments, as prefaced by #1, then said person is a classic novice/amateur in terms of building and sailing. The sailing side has been addressed so he now moves into the building side.

Said novice will have zero experience in all aspect…and that is the distinction. Thus the novice has no base line to judge any comments that comes from Brent. But has already been sold in #1, so why question the messiah, all sounds logical…yes?

Well, by Brent’s own account he works for one month a year and sails the 11 remaining months, and has been doing that for 20 years.

So, that is just 1 x 20 = 20months experience. Of that 1 month he works just 90 hours, he claim of the hours required to build the boat, yet no one other than Brent can achieve this. This is 90 hours x 20 = 1800 hours of experience in building. That is clearly much more than a novice.

Just me, for example. I have been in shipbuilding for over 20 years. It has been my day in day out job. Working on the shopfloor in the design office all areas. In this time having done all methods of construction humanly possible. Much more than Brent’s two methods of with/without frames.

So, as a rough guesstimate I have 40hrs per week, x 48 weeks (4 weeks hols) x 20 years, which equals 38,400 hours of experience compared to 1800hours of Brent.

You can make up your own minds to the conclusions.

BTW.
Great pots by Welder/Fitter, aka Mike and Northman.

Good info from Tazzman in this pic’s above too.

 

Frame time

Brent
I know I am not the speediest at building frames but so far it takes me about 5 hours to build 1 and that is hand bending deck beams and all
I think my 3 weeks longer to build is going to come in close. I will try to keep honest track. I'm only working on it 1 day a week at the moment, busy at work and to dang hot to do anything in the afternoons.
Only thing right now is were seriosly considering swiching to aluminum before I get to far into it, Got the wife convinced it would be better LOL
Tom

 

There seems to be confusion over this 90hour thing, which is the time that Brent figures, here, that it takes him to pull the hulls together & place the deck, house etc., but does not include welding & "detailing". I went back to a file I kept when I was first researching the Brent boats, and have continued to add to since, & found this:

> --- In origamiboats@yahoogroups.com, "brentswain38" <brentswain38@>
> wrote:
> >
> > I estimate 100 hours for the shell, 100 hours for the detailing
and
> > 100 hours for the welding, at $30 per hour for the steel work.
> > Interiors depend on how expensive an interior you want . I can
rough
> > one in on a week .Material costs depend on how good the
scrounging is
> > in your area. Where there is an oil, pulp or sugar industry
there is
> > usually scrap stainless.
> > The last 36 I tacked together and detailed took me about six
weeks .
> > the owner did the welding. You could easily hire a welding
student to
> > weld it up for less that I' could do it for. I have recommended
that
> > to most owners.
> > Brent

As Brent recommends to the prospective builder that they build other parts prior to starting on the hull, I have no idea if he is including the time to fabricate the keel(s), etc., in this estimate. So, that is an estimate from one whom has built how many? How about the first-timer? x2? x3? more? See, it all depends on the individual. I don't wish to mis-quote him, but I believe that Wynand has built quite a few of Dudley Dix's 38 footers. Will a first-time builder of the same boat be able to build the same boat, to the same quality, utilizing the same amount of time? Highly doubtful. I'd be willing to bet that the first one took him much longer than the last one, and he was already a boatbuilder at that point, if I recall correctly. Then, of course, if we consider what is further down the road(interior), one will spend time on scribing templates for bulkheads &/or other interior fixtures. We must remember that what we are targetting is the time requirements for the finished product. As well, for Brent's design alone, there are numerous differences in interiors, windows, deck fittings, sail rigs, etc., and on how much time one can afford to give their build each week, as Tom has just illustrated. Call it "snake oil salesmanship", "smoke & mirrors", or simply, "misleading", it is a very subjective estimate.
Mike

 

And a lot of other people have commented something quite different, about your poor design about your poor welding methods and about the low value of a BS boat. And particulalry that a newcomer should buy a used boat and save all the time and effort and gain some experience before falling into your hands.

If it is a fatigue issue its a game of cycles and stress levels aka S-N curves.
You have several serious stress raisers 'designed' directly into very highly stressed parts of the hull. The S-N curve will take you down eventually tick tick tick............ On a well framed boat the redundancy will pick up where the fatigued bit let go. On you already poor design theres no redundancy. Tick tick tick............

It's more likely to show itself right when you most need it not to :!:


You said before on this thread that you drew the lines and designed from them and derived a stability curve from them.
But you simply made that up. You are a shocking fibber.
You have neither the lines nor the offsets table nor the properly derived GZ curve. But you like to tell people you do when it suits. That illustrates the reliability and honesty of what you say and do. By your works you are judged. And also by your designs.

So where would you like to go from here. I think the phenominally strong conic sections myth deserve collapsing. The curves you think can replace transverse frames in boats to 60 feet. But you are unable to say how or why or by how much. Or do you know by now ?

 

I am still not sure about the whole 60 foot thing? Is there any physical reason why the ballpark of 60 feet is an acceptable limit?

Why not 80? 40? 100? 20? 500?

I mean if the technique is good, why not just spec thicker plates?

Or maybe... just maybe.... at larger sizes you can have a thinner hull skin if you have internal framing? And funny enough! This applies for smaller boats too!!!

::caveat for anyone who wants to have a serious math based physics type discussion::

::further caveat, skin thickness is nice for stuff like insulation, puncture resistance, rust resistance, carrying more strength in tension, etc, etc::