On Tuesday, April 4, 2017 at 10:18:43 AM UTC-4, wrote:
After removing all the gelcoat, a friend recommended applying a very thin cloth known as Vail to fill most pinholes. We brushed on epoxy and rolled on the Vail, followed with thin peal-ply, then squeegee'd it out with excess resin toward the trailing edges of the wing. Not sure it worked all that well and took two of us 4 hours + $400 bucks for Vail, resin and peal-ply. In some areas (near spoilers), we trapped some resin between the Vail and peal-ply which was full of pin holes!
I think the concept is good, but next time I believe I'll skip the Vail and just brush on epoxy and cover it with peal-ply. The resin has got to fill most pin holes and the peal-ply will leave the surface ready to prime.
Would like to know what others are doing?
JJ

If surface does not need any replacement of cloth for structural reasons, I have found the following to work best for me.
1)Blow as much dust off the surface and out of defects as possible.
2) Apply PCL Polyprimer using a 4 inch foam roller using a good bit of pressure on the roller. The first coat is not all that thick and the objective is to work the filler into the pinholes. I use 907 white for these coats.When it has tacked off I roll a second coat which covers and lets me see the defects that are not filled.
3) Spot in all the defects I can see, then spray one coat of 901 gray.
4) Sand and continue.
This usually gets 90-95% of the pinholes for me.
Good Luck
UH