Re: To gap or not to gap
I hate to contradict others, but I'll throw my 2 cents in
I wouldn't leave a gap on the edges to the hull, but I always leve about a 1/8th inch gap between sheets of 3/4" ply. Why? Not for expansion, but to allow sufficient epoxy(Mixed with milled fibers & a bit of cabosil) to fully penetrate the joint. If they are butted together, you can sitll get some epoxy between the sheets as you assemble, but I feel more comfortable sealing this area after the sheet is down. (Always seal the ends before installing, though, with some resin soaked in.) I liberally use the epoxy mixture, wait for it to cure a day or two depending on temperature, then sand it smooth...I use this same mix where the plywood meets the hull, for a fillet. Then tab the plywood sole up the hull about 3 inches, followed by a layer going up 6 inches. Sand everything smooth again with an orbital sander, then glass over the entire sole and up the hull about 8 inches. All that's left is to decide is if you want paint, carpet, or the bedliner some are using. Just make sure you cover it with something, as the UV light will break down the epoxy I hear. Most of this is a personal choice. In reality. the butted together ends with a thin epoxy, and glassed over are probably just fine. I just like to do it once, with overkill, and know I'll never have to do it again. The negative side to this: If I or anyone else has to tear into a boat I rebuilt, it will be 3 times the work getting through the extra layers of glass, etc. I figure by the time that becomes necessary, hopefully I'll either be long gone or 130 years old
