DiY pontoons.

Catrease01

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May 31, 2015
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Ok ao im new to the forums but ive been reading dor awhile. Im going to make a miniish pontoon that supports 1500lb. Overall. The toons will be square 2ft wide and wooden. This doesnt have to last decades. What thickness wood should i use and shouldbi cover it with something? Sheet aluminum isnt an option for me. I was thinking along the lines of a paint or something
 

henleyhale

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Step 1. Get this idea out of your head its a bad one
Step 2. Pick up destroyed pontoon boat for the price of the trailer and rebuild the floor and transom. Youll be just as proud of your accomplishment and youll save alot of money vs. The one your going to go make a hazard at the end of the dock with.
Step 3. Brace yourself for sarcasm from the forum.
 

GA_Boater

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Welcome aboard. Cat.

Gee, henley - What's wrong with wooden boats? That's how it all began.



Cat - How large a boat are you thinking of building and what do you plan to use it for? Check out some plans on the WWW for some ideas. Some have material lists to give you an idea of cost. Depending on what you want henley's idea of picking up a "junker" may or or may not be the best way for you go.

Here a Google for you to look at. https://www.google.com/search?q=wooden+pontoon+boats+plans&ie=utf-8&oe=utf-8

Here is a free plan for a 12 footer - http://www.jemwatercraft.com/pontoon.php and a Glen-L plan for an adaptable 12-28 foot toon - http://www.glen-l.com/designs/house/huckfinn.html
 

HotTommy

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The following thoughts are off the top of my head. Use with caution.
A 1,500 pound boat must displace 24 cubic feet of water to stay afloat. You probably don't want' your pontoons completely submerged, so plan on them displacing at least twice as much space, or about 24 cubic feet per pontoon. If they are 2' wide, they'll need to be at least 12' long and 2' high. ... Unless you plan on bumping into rocks, docks and hard things, the main consideration for covering the wood is to make it water tight. I suppose you could use that aerosol rubber coating spray they advertise on TV all the time, but I think fiberglass would be a much better choice. Keep in mind that no matter how hard you try, the insides of the toons will probably get wet sooner or later. It would be best to protect the wood by fiberglassing both inside and outside. ... The biggest structural challenge for the pontoons will be the force of the water trying to push the two long sides and the bottom in. A simple solution would be to place wooden reinforcements every 2' or so inside the length of the toons. I'm visualizing an inverted triangle with the points truncated to fit flush against the sides and bottom. I'm sure there is much more I haven't thought of, but maybe this will give you a sense of the magnitude of the engineering task you are undertaking. ... Good luck.
 
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Catrease01

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May 31, 2015
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Ok thanks to everyone who kindly replied. 1500lbs is with bonus weight. Itll be meant to hold me and my wife (together we weigh 250...wet) and an extra person. I figured 1500lbs is with safety room. 1500 /62.4 = 24 cubic feet. 12 per toon. Or 2 6ft x 2ft x 1ft toons. I want it to be wood because i have lots of it.y question really is should i worry about the thickness? And should i polyurethane them for waterproofing or try and skin it with something
 

BrianMc

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I have to somewhat go along with Henley. Unless there's some nostalgia involved here,or a craftsman looking for a cool project you will likely be money ahead finding an old tube and frame to use. Building stout enough wooden tubes will also weigh more than aluminum. Keep in mind when looking at the weight capacity of a two tube toon that one tube has to carry more than the total capacity without submerging. Otherwise if everyone moves to one side it'll flip over. I've seen a formula for this somewhere. Try googling pontoon capacities.
 

MinUph

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Jun 5, 2011
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As a fellow woodworker I commend you on your project. I would think 3/4" thick lumber properly glued and screwed would suffice. Just a guess mind you. As far as sealing and finishing I would try the best sealer you can find and use many coats. Probably 6 or 7 then a finish coat of the best finish you can find. I don't have any recommendations on these. I would hope this will be pulled out when not in use. And stay way from salt water. I would love to watch the progress so keep us pictured.
Have fun and be safe.
 

Jeep Man

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Oct 17, 2008
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Welcome aboard Catrease. Personally I think it is very doable. Whether it is financially viable over a set of used or factory seconds pontoons I don't know. I get the feeling you are not in USA or Canada. If aluminum is not an option, covering wooden pontoons with fiberglass would be your next best option. The shape and design of that "box" will be the key to it's success.
 

Illinoid

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Sep 28, 2013
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I started trying to figure our how to build a toon out of some big cottonwood trees on my nursery, over 2 ft diameter but ended up with an early aluminum toon. I still would like to build a pacific proa some day and there is lots of engineering info at proafile.com that you could use to build a wooden toon. You can also glue together foam insulation and wrap it in fiberglass. Nothing wrong with being creative, as boats go, pontoons are in their infancy.
 

jbcurt00

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3/8" ply will be sufficient to build the exterior tube shape and plan to build bulkheads,. FYI building the tubes w some flare or taper can make them more rigid because of the compound shape. Thats why 3/16" luaun is plenty strong enough for my knock down wooden boat.

I envision a wooden tube and support structure that could be assembled for use, then disassembled for transport.

But no, i dont think 1X2X6 tubes will be sufficient.

No matter how you plan to propel the bost, you'll want some taper to the tube, which decreases their volume.

I'd use the boat stitch and glue method to make the tubes. Use 3-4oz glass (2layers) and TiteBond3 waterproof glue instead of resin to seal all the seams. Then epoxy or urethane the wood to seal it.

Google Ken Simpson boats. He's the designer or my knockdown boat and espouses the titebond3 and glass seam method. Worked great @mine.

Good luck w your project.

I look forward to seeing what you come up w.
 
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Catrease01

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I live in Mississippi. Northeast mississippi. In a county of almost 40000. No factory near here and nothing on cl or scrapyards. Plus i have plenty of wood in my stores. Enough for a few boats. The cost isnt the problem its the experience building a floating mobile pontoon with my own hands any fool can buy something. Me and my wife are 115lbs each. 1/4 plywoods is 22lbs ish per sheet. Not sure how much epoxy weighs though. Cant be that much well c. If what ive found is the right epoxy its like 50to 60 dollars per gallon thats not to bad imo. From what i read epoxy is best. With a paint over it to block uv.
 

HotTommy

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I get the impression that experience will teach you far more than all the advice on this forum ever could. Good luck with your project. And let us know how it goes.
 

southkogs

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GA gotcha' the Huck Finn, but don't rule something like this HERE out either.
 

GA_Boater

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There are all kinds of plans and in some cases full or partial kits. I want to build a Power Yak from Glen-L. I think it's just cool.

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Ooops, Sorry. I'm starting to hijack.
 

Catrease01

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No worries. I do have a question if anyone knows the answer. Ofr can atleast lend some direction. What does a pontoon thats taller than itbis wide do? For instance a pontoon that is 1ft wide and 2ft tall vs vice versa. I get that the greater the horizontal sa the more friction there is but what does it do if u turn it on its side? Does that just make it sit deeper in the water than the other direction ?
 

GA_Boater

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A wider toon won't sit as deep in the water so it doesn't have to displace as much water. A 2' X 2' toon is probably better all around.
 

BrianMc

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Oct 2, 2010
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You will displace the same amount of water either way you turn it. As far as strength goes for the square tube here is something to think about when reinforcing it. At 6" deep your applying about .25 psi to the bottom. Doesn't sound like much,but a 2'x8' section would have around 600 lbs pushing against it,or 36 lbs per sq. ft. Double that at 12" deep.
 
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