Hello my husband and I are building a catamaran made with marine plywood (Gaboon from France). It is considered very high quality and it cost a fortune to have it delivered to Australia. Right in the middle of building the second hull, we found out that there was a panel with a quite deep void (of course the panel is already part of the outboard side of the hull and we can’t really see how far it goes). What would you do? would you rip the sheet off and start again or simply inject epoxy in it? thank you very much for your suggestion
I think I would sand down to the void and around it then build it back up with layers of fibreglass cloth. You could try finding the top of the void then drill two holes halfway into the plywood and fill up through one hole with epoxy if your still not 100% cut a bit of plywood and epoxy it over the panel. You should be able to get marine ply in Australia there are a few boat builders here that point you in the right direction http://www.glen-l.com/phpBB2/index.php
Best take to it with an angle grinder with sanding disc on it ( 40 grit) and cut away the void area making a hole with shallow tapered sides until you are well clear of the void area. Put a backing piece across the hole with kitchen wrap or similar on it as a parting agent, then lay in layers of glass cloth in epoxy until slightly over filled then fair back to the true surface.
I’ve often said that the problem that cant be fixed with epoxy and fiberglass cloth has yet to be found, thats not quite true but for sure it will fix a lot of things, your problem being one. Good luck with that.