Building a small work barge with plywood

This is dredging up a really old idea, but how about putting the lifting mechanism on a truss system to spread the weight over the length of the deck? I remember they used to use a similar system about 150 years ago to add rigidity to old steamboats.

 

Thanks sam sam. Interesting stuff. Each picture or article gives me more stuff to add to the design. Everybody keep sending me links or ideas. Thanks

 

Now comes the problem. Marine plywood is far too expensive for this project. Whats the best alternative generally available. I wish advantec was not a chip product. It has potential elsewhere.

 

The idea about supporting the lifting mechanism is what were thinking about. We've got some 3 inch square stock that were thinking of making a support frame to bolt to the deck of the barge and tie down somehow to the verticle support inside the barge. Maybe chainplaates or something similar. Still wondering if he egg crate will have the longitudinal and lateral strenght verses internal beams or frames.

 

Depends on your skills, timber source, and time you can invest. A triple planked (or even 4) hull can be a good alternative. The Atkin plan mentioned by Sam would be my recommendation as well. I will have a look at it, and maybe come back with another comment.

Regards
Richard

 

Here in the states you can find 3/4" exterior luan plywood with many plys from some lumber yards. If you have a Carter lumber they often carry it. The price is about the same as 3/4" AC exterior. There are very few voids. Good stuff in comparison to the fir/larch plywood.

 

The problem Indian is your budget. Gonna be tough to build something 24 x 12 that cheap.
Perhaps investigate the" Foam Billet " technique. That foam in pretty cheap and its used on many floating dock projects. Not the best for the job, not a true barge , but you could probably put together a dock float with common pressure treated framing and some kind of ac plywood deck, really cheap.

 

The foam billets dont work real good up here because we have muscrat problems. they love any unprotected foam. We used shrink wrap over the foam for a few years and that kinda worked but now were slowly replacing the foam and blue barrels with black commercial foam filled floats. The docks that we build cost us about $30 per sq ft. so thats not as cheap s you would think. We could still build something like we have now but i would really like something like what we have been talking about. Even if we only get about 15 or 20 years out of it that would be ok. Were still working on our cost estimates but my worker thinks he has the numbers under control. Were pretty resourceful up here in the north country.

 

Cool...guess you know local supplies. Id have a hard time putting together enough decent plywood for your budget. Good quality exterior ply, well sealed and proteced might do the trick.

 

Well scrap the $3000 estimate kind of. That was for a 12' X 24' X 24". Only 2 feet high. Although that would probably work for our needs i was thinking more in the line of 3 or 4 feet high.

 

This thread may prove relevant to your project.: http://www.boatdesign.net/forums/classification/deck-loading-35482.html

 

I think people overthink too much about leaks and sinking.

You should give more details on what you will use this barge for, and the conditions, etc. Do you want a barge you can put stuff into or a platform you can work off of ?

An egg crate design would be a pain to glass all the joints and all the joints will create rot situations. If you want 15-20 years of service from wood, I would think a real basic structure that you can access and squirt down with preservatives every few years would be best.

Your original barge only cost $1000 and worked until a storm wrecked it. How was it built?

Possibly you should look for a "derelict" house boat that you can strip off the cabin and make into a work barge.

 

Marine Pontoons

How about these plastic pontoons:
http://www.plasticpontoon.com/web/downloads.html

http://www.plasticpontoon.com/web/downloads/36-inch_cut_sheet.pdf

....medium density polyethylene (MDPE), 3/8 inch thick

 

Your right about the original barge working for 25 years although it did have some inherent flaws that we plan to correct on the new one. We did look at rebuilding using the old design and enlarging it and using commercial dock floats. That would work fine but the cost for just the flotation was the deterrent so that's why we were looking at different options and came up with this one. The egg crate design is a lot of work. And a lot of glassing. Chick, my employee, thought that would be a nice alternative. It all boils down to the final cost which were laying out and comparing. We also want this one to look better and more professional rather than an old dock with a winch on it. The old system had floats that leaked or came loose and the crane or gantry system that we had was pretty cobbed up. Lots of thinking and ciphering to do. I do appreciate all the info that i am getting though. It helps with the design process.

 

perhaps the thread on building a house boat would give you some ideas