air bubbles when spraying pva

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#1

Iam haveing trouble with little air bubbles on the surface of the gel coat that is from the pva.
Iam waxing the mold a couple of times, then spraying a couple coats of pva. spray gel coat and so on…

when I pull the product it looks perfect, like the mold suface, then I wash off the pva and there are little void pin holes in the gel coat surface from the pva.
spraying with automotive air gun at 70-90psi

any other ways to eliminate bubbles?
what other release agents are good ?

#2

You have to make sure the PVA is fully dry and you need to mist on several light coats, letting it dry between them…at lest that works for us.

I use and like semi permament mold releases but with newbies students, it is cheap insurance…

#3

the last coat was pritty thick that could have done it!
it also leaves a texture on the gel coat so I have to wet sand after!

Have you tried useing any auto waxes to get a good mold surface?