> Hank, When using luaun, is it necessary to use exterior grade or is plain
> old underlayment OK?

I've built several cheap boats with interior grade plywoods. There are very few exterior grade plywoods available in 1/8 and 1/4. Most suppliers do not stock it and must order a few sheets for me and that jacks up the price. Glues for interio and exterior seem to be the same these days. After the boat is glassed over it does not seem to matter what is inside.

We've used masonite as a core and glassed over it. I don't think I would build the complete boat this way. The part we needed was a visor over the cabin house. The shape required a long curved panel. Cutting it out of masonite was cheap and worked very well.

Bed sheets can be used in place of polyester cloth. Look for them on sale. You may want to wash and iron them to get them to lay flat.

Polyester tooling resin will save money too. Five gallons will cost $95!

After reading this post you may think all I build is junk. Some of my cheap boats are over 5 years old and showing no sign of falling apart. I usually win first place in the wooden boat shows I enter. You do not have to spend a lot of money to have a beautiful boat.