Hi, I am new to this site and new to the composite scene, I have been trying to make a mould with no luck as the gel coat is sticking to the paint. I was just wondering is a poxy g coat the same as tooling gel coat?
Try to use search, i’m sure you will find the answer pretty easy.
What paint? What release agent?
Typically epoxy based products are called a tooling “surface coats” and polyester based products are called “gel-coats”. The release with epoxy based products can be more difficult.
the first time i tried it i used wax and pva and that didnt work. the last time i tried it i used just wax. the paint is just the rattle can sort.
Don’t use cheap 1K paint from a hardware store! That will make Problems with all release agents.
okay thanks am best off using bare metal or is there a certion type of paint to use. i was going to try and make a mould of a wing(fender) will it react with the factory paint?
The factory paint should be O.K. I would test it in first though.
thanks a lot. just another quick one. could i go over body filler or will it need painting?
Over paint the body filler or it tends to stick.
Are you using epoxy? If its with a slow hardener you may find they tend to be more corrosive on your mould surface than with a standard or fast hardener. They can etch into the mould surface with extended open times when a faster hardener would cause no problems with the same release agent.
Do a test sample.
Just a couple of things I have used,
Use an epoxy Paint.
Wax your Part/Mold at least twice then wax again and set outside in the sun to heat it up, then wax again. sometimes when your making a mold waxing the master part 5 or 6 times is a good idea.
remember as the resin cures it heats up a bit and can cause issues with your wax, kinda like a post cure on your wax.
BTW, early in my molding experience, I used to use rattle can paint successfully on plugs. I would let it dry for 4 or 5 days, sand, polish, wax 4 to 5 times, let the final waxing set for at least 1 hour, and I always used PVA. The PVA must create a continuous film with no holes. The PVA will block any chemical reactivity. Rattle cans and just wax seemed to always stick.
I now use PPG Deltron DC3000 (clear-coat) to prep all my plugs. I use Frekote FMS sealer, and Frekote 770-nc to provide the release.
is there a web site that i could get these from?
You can get smaller quantities of the Frekote system from Soller Composites.
I get the PPG paint products locally from an auto parts shop. I don’t know if anybody sells it via the internet.