Wood boat with Aluminum bottom

[Wavewacker]

Considering a flat bottom jon boat 5' beam at the bottom and 24' in length.

Why can't you use an adhesive to apply a sheet aluminum on the bottom to seal and provide durability?

And, apply the same to the sides from the bottom to just above the water line? At the seam or joint what would you use to seal it, class cloth on the wood and then apply aluminum over it? Would/Could you use an aluminum channel/angle and apply it with adhesive?

Or cut the bottom out slightly larger and bend the edges up, cutting V at the corners and folding them upward over the edge?

No welding allowed!

Plywood or planks....

[PAR]

Unless the aluminum was fairly thick, you're not going to gain much by way of abrasion resistance and very little penetration resistance. You could epoxy on 12 gauge aluminum, but now you're into the range of a welded aluminum structure and can skip the wood all together.

In fact, I'll suspect a Xynole sheathing over plywood is better at abrasion protection, then 16 gauge aluminum sheet glued to plywood.

There are ways of toughening up a plywood Jon boat without resorting to a material as costly as sheet aluminum (in the thicknesses that would be effective).

[Ike]

I agree with PAR. Adding aluminum sheathing would really gain you nothing, but would add weight and the complication of using an adhesive that would bond to both wood and aluminum without eventual delamination. I don't think it would be worth it.

[Wavewacker]

Thanks! Just a thought to get the advantages of each, alm on the outside, wood on the inside, but your points are well made.

Any suggestions to better protect the hull. Lots of rocks. More plywood 2 -1/2 inch sheets?

This is a brother-in-law, a boat to share so to speak but I doubt I'll use it much. The other thoiught was just a food frame with aluminum sheet without fasteners below the water line. Neither on of us can weld enough to make a boat. 12 guage. BTW, we can get a good deal on sheet goods out the door, but shop time is not worth it.

[Ike]

I would just put two or three skegs (or runners) along the length of the bottom. Then the skegs take the dings and bangs and the bottom doesn't. And, the skegs are easily replace if neccessary. Where I am the shorelines are all very rocky and this works well.

[michael pierzga]

Sheathing a boat works for special applications. When I was a kid we would sheath small wooden skiffs with sheet metal, aluminum, so the we could operate the skifffs as ice breakers. The metal has no structural value and was ruined or peeled off by spring. Many wooden fishing boats have metal sheething to protect planking from gear chafe.

[PAR]

Aluminum is very weak, flexible and easily abated. Steel is a different story, but neither is a really good choice over plywood in small craft.

On many of my small skiffs, I spec thick, double bottoms with runners to offer some sacrificial elements as well as a touch, thick bottom to fend off rocks. 'Glass or Xynole sheathing would work well also. The choice is yours, but the sheathing will be lighter then a thick plywood bottom.

[Wavewacker]

Par, neither one of us ever worked with fiber glass, that was part of the idea as a quicker and easier way to go.

I have not heard of Xynole, but I looked it up. A poly cloth used instead of glass and what I read it seems to be in favor and perhaps more durable, didn't see anything about the cost.

All this time I assumed epoxy and resign was rather cheap, it's way expensive for some of that stuff, I can't imagine doing Bolger's Tenessee at 32' and glassing it as it would add thousands. But that's my idea, not this deal with my in law.

Anyone have any idea what the cost is to glass say one square foot? Or Xynole and epoxy? Have no idea how far a quart goes or a gal. Might as well consider all the supplies that go into a build and estimate what it costs to do one sq. ft. finished and painted.

Skids, will do...