Guys I built a mold and put on my tooling gel coat. Waited for the set up then started my built up for my mold. When I put the resin on the gel coat any where it’s on the Clay it blisters the tooling gel coat. What can I do on my next mold. I have a big one with a lot of Clay but I can’t afford for it to blister.
you can use PVA over the clay, that might shield it from interfering with the gel coat. But PVA the entire thing, not just the clay. It’s best when sprayed on, though I always use a brush.
my 2 cents.
Ok I will give that a try. Any other ideas?
I doubt it has anything to do with the clay. More likely you have applied the tooling gelcoat too thin over those areas, causing it to alligator when you put the resin on.
If it was anything to do with the clay then the issue would occur when you apply the gelcoat, not the resin.
True, good point… I’m with Hanaldo. I didn’t think about that…
Did you brush or spray gel coat… I know if it were me, I’m usually brushing and try to be extra careful over the clay… I could see myself doing just that.
I brushed it on. But I didn’t have any other problems except where the Clay was. The gelcoat doesn’t want to stick to that Clay so it like runs off of it almost
I see… well maybe the PVA would buffer the surface so it’ll stick… Maybe do a test piece to try it?
Spray or brush some pva onto the clay to alleviate the surface tension. Ez pz.
I just said that BTW 
Your gelcoat is too thin over the clay. The clay has oil in it so you need more thickness there than over the rest of the surface. Wipe PVA over the clay. Or spray PVA over the whole job. You need to mist it on at first because it might fisheye on the oily clay.