Completely new to boatbuilding and want to build a simple boat

Any orange store plywood needs to be tested. I bought a sheet of 5/8 ply from them years ago and just running a screw thru it delaminated it.

Boil test for sure.

 

These are examples of interior not exterior rated plywood.

Thin exterior plywood is not readily available.

 

The

The first link gonzo posted says, suitable for interior and exterior use. Lawn decorations were a specific example.

The second one just said underlayment for general construction. I couldn't get a price on it because the HD site only gives me information on products in stock or available within 100 miles of me. What was the price on that second link?

 

If plywood is so hard to find use planks instead.

 

I don't care what the rating may be. I have built boats with that material and they lasted several years out in the weather.
The second sells for $21.38

 

Anytime questionable materials are used in boatbuilding; just test them. Screw test, boil test, look for voids.

 

Both of these are INTERIOR plywood. They will fall apart when left in sun/rain. I been there, did that.

Unless you can store the boat out of the weather completely (no sun or rain), don't use interior ply. For a few more dollars, at least buy plywood with Exterior rating (that's the glue's rating, not "rot resistance").

 

Yes, I'll save anyone the effort for HD's "Hardwood Plywood Underlayment Specialty Panel". Used a sheet for cabinet back panel, and boiled a scrap. Fell apart.

 

That is totally incorrect. With a coat of paint they will last 3 to 4 years outside. This is a photo of a dingy I built in less than a day, including a coat of paint. It was good enough that it got stolen three years later.

 

I find that HD does major mill buys of the cheapest they can and their qa is always a question. It is quite possible you are both correct. The likelihood of exterior glue qa by them isn't.

I bought a sheet of 5/8 ply from them and the glue was so weak, a screw delaminated the panel. I figured it was a fluke spot, but the entire panel did it...

 

Yes. I've had whole panels delaminate in my shop, while other panels, of the same rating, warped and bent and twisted outside in the snow and sun without delaminating. Go figure.

-Will

 

Call Dixie Plywood. That's who supplied the marine plywood to the retail outlet I used. They are wholesale only but I was able to special order it a long time ago and it worked great.
https://dixieply.com/branch

 

These facilities near you may have some good information.

 

The OP asked for materials to build a boat under $200. Marine plywood will not fit the bill.
@RO147 : build a boat with cheap materials. You are trying to learn, so it will show you what the next boat should be. After you try it in the water, you will have new ideas about improvements. Good luck

 

Ease up on the negativity. Looks like you guys run off the OP.