Mold Release

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#1

Hi everyone,

I have a plug that I’m going to make a mold of and I have questions about mold release.

I have currently went through 8 coats of paste wax on this plug and I want to see if I can skip the PVA and just apply the tooling gel coat. The reason I want to skip the PVA is that I don’t want the marks that it leaves on the mold. So can I just put more layers of wax, say 15 times etc? I know someone that tried using just paste wax before but parts of the plug got stuck. Any input would be appreciated.

#2

Hello from FG site? :rolleyes:

Use high temp mold release wax like from Meguirs as there are differences in std. wax and mold release wax. Also, most beginners buff away all the wax…

#3

Four or five coats of a proper mould release wax should work fine, and if there are any areas of the mould where you could incorporate a schrader valve, then compressed air will aid greatly with releasing parts, which is always a little more difficult on a new mould.

#4

The paste wax that I use is the Finish Kare brand and what I do is I apply it and let it dried. Then I wipe it off after. Is this brand good enough and is this the correct way to use the wax?

Thanks

#5

I use TR high heat wax. It is my only release wax I use. Never had a problem with it. I don’t use PVA because the wax works perfectly fine

#6

Also, if you mix a too hot batches of the tooling gel coat or too many layers of the reinforcements at one time, the excess heat will melt the wax away too.

#7

Does the difference between brushing on the gel coat and spraying make the difference also? I noticed that when I make parts, the sprayed on gel coat ones de-molds somewhat easier.

#8

I brush on tooling gelcoat and I only use the TRG high temp…never use pva.

Havent had any parts stick on me yet.

#9

i noticed when i first started, i never really polished till it look like a mirror. then after polishing really REALLY high, and got that look. and used pva, it never stuck. not i want to use wav on my parts. pva is so much easier to put on thou. BUT its hard to not get bumps, dust, etc

#10

One could always use perm mold releases like Frekot products. Not sure on cost though.
You apply 5 layers with 10min dry times. then you don’t have to recoat for at least 10 pulls later.