Uncured tooling gel

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#1

Ok I figure I’d ask since someone has probably had this issue…

Sometimes, in certain areas my tooling gel doesn’t cure. It’s typically around where I do clay work. Meaning if I bridge the edge of the part to the flange it’s that area. It may be only 1/4 wide or even smaller or larger. The gel coat I don’t think is any thicker or thinner in that area.

I use frekote nc770 and then dolphin wax. I’ve had this issue before but just deal with it and fix my mold later on after I pull the first part.

I’m thinking its moisture but is there any way to fix this or is my best bet to just dremel it out then pop some new tooling gel in there vs risk pulling a part and potentially pulling up more than just that section.

#2

Get some different clay. Ideally use plasticine. It’s possible, even quite likely, that the clay you are using contains sulphur. Whilst some gelcoats and resins aren’t affected by the presence of sulphur, I know the one type of tooling gelcoat I’ve got here is affected and doesn’t cure properly.

Honestly, I recommend getting some filleting wax. It’s more expensive, but in most cases it is actually reusable so it takes a long time to go through a block of wax. And it really is THAT much better. It’s one of the best products available when it comes to making moulds, it really is. Can’t describe how much quicker, easier and nicer it makes the whole flanging process.

#3

I was really about to buy filleting wax and now regretting I didn’t!

Is there any way I can fix this issue? I’ve been using the same clay for about 3 years now. It’s a combination of I think whatever fiberglast sells and over the counter clay from a crafts store.

#4

Perhaps PVA over the clay would form enough of a barrier, but even then I wouldn’t trust it. Sulphur has a tendency to just get into things and ruin them. It’s probably your best bet though.