Fairing and glassing

[Helmsman]

I have been restoring a 1967 (hot) moulded plywood Albacore class racing dinghy. The plan is to glass it on the outside and epoxy it on the inside, but first it must be faired. Sometime in it's past it was stored on a poorly designed trailer and the bunks caused hollows in the bottom on each side of the centreboard slot. I have made up 1/16 veneers of mahogany and have built up these hollows with alternating layers until it is almost level now. I expect to fill the rest with fairing compound and long board it relatively smooth. Also, there are other lumps and hollows that that I would like to fill and fair out before glassing. But wait! Now that the fairing is down to the last stages should I be putting the glass on and failing later or should I fair it perfectly first? In the course of racing, these boats get bumped around at the dock and on the course so I want the hardest surface possible on the outside. A little experiment I did with epoxy and light weight fairing filler informed me that even a fingernail can scratch this stuff. My thinking is that the hull should be faired perfectly first then covered with 6 oz glass, smoothed and painted. My concern is whether adhesion would be a problem with this sedquence of layers. Will the fairing compound adhere well to the raw wood or would it be better to get the glass down first? If the glass should go down first, can I toughen the fairing compound with other fillers?

[BOATMIK]

I think you have answered your own question.

Fair it then glass it.

As you are looking at racing the boat is the existing hull light enough to add glass and still come out near the minimum allowed weight?

If it is going to be a close thing and the hull is reasonably sound then very light glass can have the same effect of stabilising the surface from cracking and veneer checking.

I've used down to 2oz in similar circumstances.

Michael Storer

[Helmsman]

Boatmik:
Thanks for the confirmation, I just needed someone with experience to asure me that my thinking was not way off course. As far as weight goes, by my calculations and tests, even with 6oz glass I'll be within 5 lb of class minimum weight. The hull has been inside hanging from the ceiling in my shop for the last year and a half and is quite dry, and consequently, light.
Helmsman