> A friend of mine has asked me to refresh the gelcoat of his (ancient)
> marnier. I proposed doing this with West 105 resin with 209 hardener and a
> whitening agent. Is this the best course over polyesther fiberglass? How
> compatable are the two materials, and what sort of prep work would you
> recommend? Many thanks oh guru of polymers. I await your reply dread
> sovereign.

Hi Christopher,

I don't think you'll be satisfied with the finish of a pigmented epoxy finish. You could use the epoxy and pigment as a base coat for a 2 part polyurethane (or epoxy) paint. One question though, why the 209 hardener?

In my opinion the best finish over polyester fiberglass is Gelcoat. Unfortunately if you have a large area that needs refinishing it is extremely difficult to achieve a nice finish using Gelcoat. The next best finish is a 2 part polyurethane paint, as the durability of it is close to Gelcoat, but it is MUCH easier to apply. The only draw back using the 2 part polyurethane is it's price as it's 4 times the price Gelcoat.

If the area is less than 20 square feet, my recommendation is to use Gelcoat to refinish (you'll be wet sanding and polishing though.)

If the area is more than that, I would suggest that you re-paint the boat using a 2 part paint.

One other suggestion though, try using a some gelcoat restorers from 3M (they work excellent), first step would be to use their # 9004 or # 5954 Super Duty Rubbing Compound, then # 9048, Finesse it II Finishing Material, then a good quality wax like # 9030 Ultra Performance Wax. I realize that their are other makers of compounds on the market, but these are the ones that I am familiar with.

I hope this helps a bit,

Jason

Noah's