Polyester

Hi,

I believe the caps on top of the fin and the rudder are polyester, not epoxy. They are white. The plans suggest that these only need a final sanding prior to painting. Is this correct - no pinholes? What grade of paper do you use for final sanding of this stuff?

Thanks for any help...Keith

You're dreaming!

All fiberglass parts will have pinholes!

If they are the same as the other RV's, the white is gelcoat, a polyester finish sprayed into the mold before the glass is layed up. They are easier to finish than raw fiberglass, which is LOADED with pinholes. The disadvantage to gelcoat is the weave tends to show through even after sanding smooth, priming and final sanding. I prepped mine by sanding the gloss off and filling minor imperfections with spot putty used in autobody work. You may find hidden air bubbles between the glass and the gelcoat as well. I used the same epoxy primer on them as the rest of the airplane. After a year they still look good. There may be a few pinholes but the gelcoat really does eliminate most of them.

Play with your primer

Primered the top cap after a light rub with 3m pad. Used a high-build primer.
The trick is to play with the amount of reducer to get the right coating for the fiberglass. No two fiberglass parts on this plane covered the same.