Origami steel yacht construction

[Stephen Ditmore]

Interesting, Scott. Note also that there's an origami boat on the Touch-3D site at
http://www.algonet.se/~ludesign/LUproj7.html

[Brent Swain]

This is the same system used by sailtech. In 1995 Ken Splett went to work for Gunter Richtler when he was building small aluminium workboats. Ken scaled up a set of plans for my 36 footer to 40 ft and built it for Richtler. They called it the "Fastwater 40" I spent many long hours going over the building proccess with Richtler and sold him a copy of a book I had just written on the origami building proccess.
Later , while I was away cruising the South Pacific , Richtler ,in articles in Cruising World and Pacific Yachting , claimed to have invented the proccess on his own. The two magazines later published corrections of the claim.
It would be very difficult to fully weld watertight bulkheads in any small metal craft without severly distorting the hull. Fortunatly, it would take a very long time for water to work it's way around the edges of a well bolted in bulkhead if it were foamed in place.
The need for watertight bulkheads is however doubtful in small steel yachts as the likelyhood of ever punching a hole in 3/16th plate is remote.
As for making a steel boat unsinkable, it takes 1 inch of foam to float 1/8th inch plate and 1 1/2 inch to float 3/16th. You only need to calculate the percentage of metal in ballast , engine and other things that don't float, then increase your foam thickness by that percentage, plus a bit of overkill. Your wood work has it's own weight in buoyancy as it weighs half as much as water on average. The sprayfoamers machine has guages on it which can tell you the amount of buoyancy you have after the job is done.
Years ago a friend was working on an aluminium 34 ft "Saugeen Witch. It was a bare hull with about an inch and a quarter of foam in it. They left the boat on a tide grid and went for a few beers. When they got back , they found that a thru hull had been left open and the boat was full of water and floating with about a foot of freeboard.
Brent Swain

[Brent Swain]

PS Gunter Richtler founded and runs Sailtech.
Brent Swain

[Brent Swain]

Frames can be either transverse or longitudinal. Chines , decks, and centreline structures constitute extremely strong longitudinal frames , which are far stronger than any transverse frames . In multichined hulls they are often much closer together than transverse frames and thus often make transverse frames structurally redundant Making an origami sheet metal model , then trying to change it's shape ,will give one a clear example of their redundancy.
Longitudinal stringers are far more effective than transverse frames as they are ,and support portions of arcs. It's much easier to bend a relatively straight section of transverse frame than it is to compress a longitudinal angle iron stringer on end ,especially if it's welded to hull plate with a two inch weld every six inches .
I've never felt the need for any type of trestle or temporary frame to pull a hull together , altho they may be justified if one is building a series of identical hulls.
Brent Swain

[Stephen Ditmore]

Hi, Brent. I'm really glad to have you participating in this forum, and I have a question for you.

I'm advising an effort to build a "replica" sailing ship. "Replica" is in quotes because I have been encouraged to suggest features that would make the vessel faster, safer, and acceptable to the Coast Guard as a passenger vessel (not just a sail training vessel). One thing I'm contemplating is the possibility of building the subdivided lower hull of aluminum up to the bulkhead deck, then building a wooden ship on top of that. The lower hull by itsself would resemble a lifeboat scaled up to about 90' with a fluch deck. Watertight bulkheads are not optional, and the scantlings should be consistant with ABS standards, so there's a disincentive to stray from conventional construction methods. I have a pretty good idea what the hull shape should look like if designed without regard to ease of contruction.

Question 1: How much $$ could be saved by making the hull developable consistant with your methods given that it is to be built with welded watertight bulkheads, and probably some transverse framing?

Question 2: Does this sound like something you'd be interested in undertaking once there's funding enough to pay you for your work?

[Brent Swain]

I wouldn't want to take it on as a project this time of year,cruising season is just beginning, and I may be heading south again this fall, but I'd be happy to answer any questions you have via the internet.
While I've seen estimats of 1,000 hours to put a 40 ft hull and deck together , I usually take less than 100 hours to put a 36 footer together working with one owner, sometimes a lot less if the owner knows a bit about steel working. Using origami techniques would save you a huge amount of time and labour costs .My book is a manual of origami boatbuilding techniques and would answer a lot of your questions. Many people have built their own boats using my book and a set of plans, with no problems.
If you want to put transverse framing or bulkheads in after the hull is together , that would be much easier than trying to fit the plate to the frames beforehand.Running longitudinals through the bulkheads would control the distortion from fully welding the bulkheads somewhat.
The french "Strongall" boats use heavier plate and no frames or longitudinals on origami boats , yet their boats pass all ABS and Lloyds rules .
I would suggest that you experiment with models made from sheet material.Whatever you can do with a model, you can do with sheet steel. If you put your plate shapes on a computer disc, and make a model off it to double check it, some metal suppliers can send your plates pre-cut using the computer disc ,for a price which has dropped drasticaly lately. This can make assembly extremely rapid.
Where are you?
Brent Swain

[Stephen Ditmore]

I'm in New York, but my "client" is in Virginia. We're not ready to go yet....right now this is a fundraising effort, but we're planning out what we want to do and how we want to go about it. Advice and participation are welcome from all quarters at
www.tallshipsacredromance.com
To qualify as a Jones Act vessel the "bottom" needs to be U.S. built. Other than that, we're open, but my thinking is to have the aluminum part professionally built and have any amateur work be on the wood portion. One guy who's well situated for the project and who has a good reputation is Howdy Bailey:
http://www.dixdesign.com/Global-Yachts.htm

[Stephen Ditmore]

Let me clarify that when I ask about your "undertaking" this, I mean as a consulting naval architect in charge of providing lines or expanded panel patterns as needed to produce the final bottom shape.

[Brent Swain]

Providing lines for a 90 footer is a bigger undertaking than I'd be interested in right now. Just draw the lines the same way you would design the underwater shape of any hard chine hull, then take the shapes off it, by computer , then make a model. The model will give you a good idea of how things will work out and provide a double check on the accuracy of the computer loftings as well as any changes you want to make before building the full sized ship.
With aluminium it would be easy. It would probably be a good idea to use extra heavy plate where the wood topsides join the metal bottom as joining wood to metal without corrosion problems is always a challenge. It would also be a good idea to make it easy to get to in case there are corrosion problems there in future years.
It would definitly be easier and cheaper to build the whole ship out of aluminium, but I don't know if that's an option.
Brent Swain
Brent Swain

Hi, my name is Aaron and I have been building a 26 footer for several years now. My Email address is aaronriis@yahoo.com

[ludesign]

Originally Posted by origamiboats

If anyone is interested in an unusual steel boatbuilding method, please have a look at my yahoo group site called "origamiboats". I'd like to know what you think.

The boatbuilding technique, which yields a longitudinally stiffened steel hull in quite a short time (a few weeks for the bare hull in some instances), has been around for many years, but most popular on the BC coast (Canada). Some have been built in Europe, and examples of the type have cruised far and wide.

Myself, I am soon to start construction on a 40 footer, which is one of Brent Swain's new designs, representing a world-class cruiser with ample room for familes. His most popular design to date has been the 36 footer.

Alex Christie

I have designed about 50 such boats since the mid seventies (using steel, aluminum, plastic sheets and plywood) and have written a program being extremely well suited for designing such hulls.

Check out www.touchcad.com

[CICCIO]

someone may tell me if exists any small boat build in origami way using plywood and fiberglass, i'm planning something like a micro and build a 1:5 model that looks good what
do you think about ? thanks

[harry tams]

Originally Posted by ludesign

I have designed about 50 such boats since the mid seventies (using steel, aluminum, plastic sheets and plywood) and have written a program being extremely well suited for designing such hulls.

Check out www.touchcad.com

Impressive. Though not in the market for your program, I am interested to know if there are any origami style boat plans available for the Wide Beamed Narrowboats or replica dutch barge. Can you point me in the right direction?

[Thaddeus]

Fascinating.

[boristhespie]

So to recap (lol) Theis method involves having patterns cut which aso have folds impresses into the sheets of metal (?) which joe blogs and others of questionable technical ability but with good welding skills can put together cheaply and quickly.

Hous fast for such a hull?