How to remove fiberglass from plywood hull

[Wood208]

I just picked up a 1953 14' Borum Speedicraft. The previous owner fiberglassed the hull and deck. Some of the glass is delaminated and lifting off nicely but I was wondering how to get the rest off without damaging the wood. According to the Speedicraft literature, the hull is Phillipine Mahogany Plywood.

Also, I have a 1957 Botved Coronet 17' utitlity in very good restorable condition that I may be selling. If anyone is interested, let me know.

[Cuyahoga Chuck]

It's not the 'glass but, the resin that is of interest. If it's epoxy it can be softened enough with a heat gun to get the laminate to peel off. It's best to work slowly.
If it's polyester resin heat may work but I have never done it.
The condition of the plywood is what it is. If it's been water damaged the verneers may pop. If it is sound the heat shouldn't hurt it.

[Larry P.]

My best result have been 3" grinder with 50 grit and a gentle touch. Go easy and change pads as soon as they clog.

[Bob Smalser]

My best result have been 3" grinder with 50 grit and a gentle touch. Go easy and change pads as soon as they clog.


...and then I'd add more glass and epoxy to cover up the marks and make all fair, followed by paint.

Saving that thin mahogany surface lam to take varnish once it's been glassed and painted may not be possible.

[Wood208]

Thanks all for the tips. Since it was originally painted when new, I planned on painting it again. A lot of the glass is just peeling off leaving bare wood so hopefully the grinding will be a minimum.

[Bob Smalser]

Thanks all for the tips. Since it was originally painted when new, I planned on painting it again.

Good.

I'd add another 3-4 oz layer of light glass fabric and epoxy, too. Epoxy bongs well to both polyester and epoxy residue. The light stuff is easy to lay and work, provides a good base for any fairing compound required, and that top lam of your Shorea plywood can use all the help it can get.

[Todd Bradshaw]

Heat works pretty well on polyester resin as well as epoxy. Grinding fiberglass off a boat is a once in a lifetime proposition if you ask me - as in -I did it once and I'm not doing it again. It's hard to find a nastier, itchier job. You will also notice that grinding is pretty tricky because just as soon as the disk gets through the hard fiberglass layers, it has no trouble cutting into the nice soft wood underneath it. You can wind up with an awful lot of filling to re-level the surface if you're not pretty good with a disk.