The good, the bad and the ugly - Steel building methods that is....

Discussion in 'Metal Boat Building' started by Wynand N, Aug 18, 2010.

  1. Ad Hoc
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    Ad Hoc Naval Architect

    Please do post, your posts are always worth reading..and who knows what may spark from it.
  2. Wynand N
    Joined: Oct 2004
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    Wynand N Retired Steelboatbuilder

    a very good question Jarl, and one issue mostly overlooked by new builders. A lot of emphasis is put down on the speed some hulls are built and this is a powerful sales pitch. When that is done by the customer, a reality shock.
    Now the expenses, time and fun starts and we have so many abandoned home projects sold as scarp.
    Another tragedy is people building bigger than their wallets allowed - easy to work out the steel cost and say, heck, not to much for a say 45 er. But, what he is not informed of is that the hull represents only about 12 - 18% of total cost of a well built/equipped boat. (BS, I see you crawl around here and do not reply on this - we've heard it before....). And costs of equipment for bigger boats rises exponentially, take mast and sails for instance.

    As for your question. I can give you two examples of boats I had built;

    1. vd Stadt 34 - Hull & deck complete with keel (lead ballast fitted), rudder, Bulkheads (steel) ready for shot blasting - 18 working days
    Completely fitted out as per plan ready for delivery - total built time: approx 5 months.

    2. Dix 43 centre cockpit radius chine; Hull, deck, keel (with lead ballast fitted) rudder completely shot blasted inside and outside and epoxy prime coated - approx 4.3 months. I must state that during this stage from the boat was started we had power sharing (lack of maintenance of generating plants - typical of African efficiency) and every second day only had electricity for four hours at the time lasting 5 months...
    Total completion of this boat ready for launch took about 15 working months with delays and changes made as we gone along with fitting out. This was a full house boat exceptionally well equipped.

    It can be safely said that the hull/deck construction, blasted and painted only take about 25% of the total build time for a professional yard working full time on the project.
    The home builder will take much, much longer.
  3. LyndonJ
    Joined: May 2008
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    LyndonJ Senior Member

    One problem with welding any metal plating is if you pull it into shape and it's got high residual stress from being pull into a tight curve, then when you weld it it distorts much more in the weld zone. You get obvious discontinuities in the curvature where the welds are. So I was thinking a pull together flat form might have some problems adding framing later.

    The best plate first methods would be flat plates with a little curvature joined at the edges. aka fully hard chine fully developable. You can build those in a cradle or over their own strongback.
  4. magwas
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    magwas Senior Member

    Please read my full post. I did not say that with origami one should not consider mechanics. I have basically said that the mechanics related arguments against origami are not based on any property inherent to the building method.

    Also, the expressions like "I think" is here to signify that (although I am pretty sure about the subject) I am not talking from first-hand experience. I regard it much better than blatantly stating and restating opinions which have already been debunked.
    If you have problem with any of those statements, please bring up substantial arguments against it. Readers won't learn anything about the subject (only about your style) without arguments supporting your opinion. And you are certainly qualified to bring up such arguments.
  5. magwas
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    magwas Senior Member

    This point have been brought up several times, so I think it is basically a valid one.
    However there are several kinds of items boosting the building cost with the size, so maybe there is some place for optimisation here.
    "Bigger" here means a boat which is aimed exactly to the same purposes like the "smaller": same number of crew, same type of usage. And it is not like twice bigger, but for example a 40 footer instead of a 35 footer.
    1. Bigger boats are usualy more well equipped. So if one can live without the extra equipment (like air conditioner, plasma TV, and the related beef in with electronic systems), this part can be spared.
    2. There are items (like material and work for furniture) which basically grow linearly (more exacly somewhere between quadratic and cubic to LOA) with boat size. My point is that those expenses are although bigger with a bigger boat, are in the handleable range.
    3. The items which need exponential effort and expense are mainly related to rigging. (What have I forgotten?) Maybe with a split rig and a less demanding sailplan (junk rig comes to mind) one could make this handleable: smaller although more deck hardware, a mast and a sail which is within the abilities of the builder.
  6. Wynand N
    Joined: Oct 2004
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    Wynand N Retired Steelboatbuilder

    Magwas, you sound like the typical wannabe steel boat (or any other) owner.
    Again, why are many steel boat project abandoned? Because people build bigger than they can afford. Read my last post again.

    Having built 19 steel boats in the past, ranging between 24 - 65ft overall, I can tell you that 5ft difference in LOA is a mayor step. Even 2ft make a huge impact on price - browse sailboats for sale and you will notice that, and that's for a reason - bigger boats are more expensive to build, period.

    Have you ever being in an empty lets say 43ft hull? It is a big hole to fill and building materials cost the same regardless of size boats is gonna be used for. If you are to build a boat as per plan to a good standard, what can you really save doing it yourself? Lets see..

    Steel pipe push & pull pit with stanchions welded to the deck? Yah, save a few bob there, regardless of the "look". What else? OK, a wooden bucket instead of a flush loo, a silly little paraffin burner instead of a nice gas stove with oven. Yes, the engine is worth something, lets swop that for something old and run down that will let you down when needed most. Also, get rid of the shiny winches in lieu of some wooden blocks and they are good for building muscles too ;)
    Not a lot saved and you will be stuck with a boat you would not be proud off and nobody else would buy down the line.:rolleyes:

    The fact of the matter; a home builder can save on everything he buys, negotiating discounts - the pros will ask you the retail price plus handling fee and over and above that, some profit.
    The biggest savings for the home builder is labour as this can easily be in the region of 40% of boat price.
    IOW, a bigger boat cannot be build cheaper than its smaller sister - regardless pro or DIY.

    By the way, I had never installed a TV, aircon, microwave etc on a boat...
  7. dskira

    dskira Previous Member

    A real pro with experience has spoken. So true Wynand. I hope your post go thru the amateur builder.
  8. apex1

    apex1 Guest

    Lets add some points to the "bigger is not much more expensive" myth, Peers.

    Going from say 35 to 45 makes roughly twice the volume, but the novice sees (and counts) only 10ft on hull, deck and maybe, mast and sails.

    Given the (rare) case we have the same accommodation, just every compartement a bit wider, more elbowroom.
    Now the novice assumes that cannot be a big factor in cost and time to get it that "bit" bigger.

    The bigger bollards, clamps, winches, windlass, stronger ropes and wire, extra insulation, even the bigger diameter in wiring due to extra length, all forgotten.
    Cabinetry, paneling, larger pumps for bigger bilges, twice the engine size (and tanks accordingly), all forgotten.

    But that is all weight, and weight costs, not LOA.

    Of course a good NA can design extra length (for extra speed) in larger boats, by adding "empty hull", read laundry, walk in cold stores etc, without increasing the cost proportional. But that game starts somewhere in the 55ft range or above (I guess) to make sense. Way above the size for the average homebuilder.

    What we see here is the ever so common reaction of the complete novice.
    They do not like and do not accept the dream gets busted.
    There must be a way to make the phantasy become reality. It MUST....
    When the experts say it is not possible, you have asked the wrong experts! Ask others, which tell you it is easy to accomplish, and the so called experts just wanted to milk you.
    Then our novice is happy (and ready to destroy his life).

    Thats the way some (at least one around here) make their shabby living

  9. waterdrop
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    waterdrop Junior Member

    wow you guys had quite a feast out of my one post, reminds me of the posts made by brent himself, really i'd just like someone with naval engineering expertise to give me a couple answer to my questions,
    Here's the thing, I do not have the piles of money that would be required to have a boat professionally built, have never done it before so the framing first than plating isn't really even an option. I've welded just enough to know that I don't have the skills necessary to put something like that together in a timely manner and come out of it with a fare hull (certainly not without using fairing compound). So the design of Brent Swains boat has peaked my interest, everybody I've talked to who has built one has been (and still are) has assured me that they are simple enough to pull together and can be done fairly quickly, I for one like the look of them to boot, the hull shape/cabin and all that is a fairly good cruising boat compromise. And they're are so many of them around, I run into several in just about every coastal town around BC and the owners that I've talked to are very confident in their strength.

    The pre bent long. frames vs. bent along with the hull frames discussion is kind of interesting, to me the it seem counter intuitive that they would be much different, but you are the engineers, although mixed in that thread is complaints of a near complete lack of actual detail about the 36'BSs, not that you are to blame for that, but I'm still somewhat skeptical about the accuracy of those calculations deviating from either method. I also wonder and the practicality of fitted pre-stressed ones in after the skin is formed? Although as I said don't really think it's necessary but would love it if someone would elaborate on different methods of doing this.

    Also the mast arch pipe bursting through the chine problem could easily be fixed with some heavy guesting couldn't it?

    And Wynand how did you know I was a woman? was it something in the way I wrote? I find it so interesting that from that one post who've garnered so much information on me.

    Just to make things clear here I am not Brent Swain, never met the guy, just read his postings, his book, seen the video of him building alex's boat in courtenay, I've looked at a least a couple dozen of his designs around the area, talked to a spatering of the owners about their boats, I would just like to build a steel boat that is tough as nails and can go around the world with a budget under 50k and it doesn't seem that any other method other than origami (which is just a name, I could can it skin first or banana peel construction or what ever -you know what I mean) would accomplish this, I would love it if all you self titled professionals would stop arguing and put you heads together and come up with some fixes to these apparent flaws, You say you're professionals and experts so let's see some evidence of this.
  10. waterdrop
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    waterdrop Junior Member

    I was also thinking of building in china maybe next summer, I have an extensive family over there and since, it seems that most anything metal comes from over there, it would be the place to do it to keep costs down
  11. apex1

    apex1 Guest

    There are no self titled pro´s here, why do you turn agressive?

    And the evidence is not to provide, because BS hides his plans (you may guess why)
  12. waterdrop
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    waterdrop Junior Member

    Well, some of you have written under your names, stuff like "Naval Architect", "steelboatbuilder" "welder/fitter" ect... leads one to think that you are calling yourselves professionals or at least something other than amateurs. Which is why I am asking you guys, that is why this forum exists isn't it? or is this one of those manly_bullshiting_sessions where you are all just patting each other one the back for reiterating what has already been said.

    Well the question of cost, as other's have pointed out isn't really about how the method in which the hull is built, the cost of materials is directly related to weight so if one boat is lighter than another it will have cheaper materials no? But they weight difference in a 36' steel boat designs can't be that much regardless of frames or no frames, it's the labour which is the large variable in a hull right? What I said is "professionally built" as in not built by me (an amateur) ie. WAGES rather than my own time of which I have lots and don't mind spending but would rather spend efficiently since to go sailing IS the goal here.

    I didn't mean to be aggressive I am just trying to direct your energies into something that is more productive than it has been in the past threads. I'm just asking about ways to build a steel boat, fast cheap and with little skill, experience or equipment. To me it seems that the origami method is the best suited for this but that there are a few flaws, pointed out by you folks, so I'll ask again, since we're trying to be constructive here, what would be necessary to fix these flaws?
  13. waterdrop
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    waterdrop Junior Member

    "but I'm still somewhat skeptical about the accuracy of those calculations deviating from either method."

    Sorry, if I didn't word that very well I meant, the calculations between the buckling potential between a pre stressed angle iron welded to the hull vs a compression loaded, It doesn't seem to me like it would make that much of a difference, and therefore seems counter intuitive that a piece already bent into a shape would resist force better than one that wants to stay straight and therefore is already pushing back. I find it especially surprising that there would be a large difference in strength between these two methods.
  14. rugludallur
    Joined: Jan 2006
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    rugludallur Rugludallur


    Since we are talking requirements lets review a bit:

    You want a boat around 36ft
    You want it to cost less than 50k

    How many months does it need to float?
    Does it need to be able to propel itself, how fast does it need to go?
    How many days of maintenance per year are you willing to put in and how much can it cost?

    At the risk of putting words in other peoples mouths, what I think most of us are trying to say is that origami is a viable building method, but that it takes no less time than a chined boat with frames to build if done properly. If you don't have the time or money to do it well now you certainly won't have the time or money to spend on copious amounts of maintenance required later.


  15. CatBuilder

    CatBuilder Previous Member

    If I may pipe in on costs:

    The hull materials are one of the least significant areas of boat building costs.

    Hulls usually represent 30%-40% of a boat's final build expense. Pay no attention to saving any money on the hull's costs. In fact, pay little attention to saving money at all, if you want a boat you can resell later on.

    The "equipment" is where the lion's share of the money is spent:

    *Cushions (interior and exterior)
    *Cleats, winches, anchors, lines, etc...
    *Safety Equipment

    This is where the money is spent building a boat. It has little to do with the hull itself, so don't get stuck on choosing any build method to save costs.

    Generally speaking, it costs approximately the same amount to build a piece of junk hull as it costs to build a perfect yacht hull (assuming no labor costs).

    Build the best hull you can and then outfit it as you would either or any type of boat.

    I'd also like to add that I'm not for or against Brent's boats, but I have to admit... I like his inexpensive solutions to everyday cruising problems.

    If you can handle re-building, rather than building, you might want to save yourself a lot of time and money and take a look at these:

    You will always be able to find a better used boat (for your budget) than making a new one, if they exist (none existed in my personal case). I'm also warning you... you won't be able to build a 36ft steel boat for $50K. No way, no how. Just look at the price of the rig and sails as well as a few winches, lines, anchors and refrigeration. You'll eat up your $50K in that stuff before you even think about hulls.

    Lastly, I want to mention that steel isn't an "inexpensive" material to upkeep. Zinc anodes are brutally expensive as are paint jobs and sand blasting. There is a lot of work involved in keeping up a steel boat.

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