Plug release agents?

General Composites Discussions Composites Talk
#1

I’m going to start molding on a plug soon and I’m wondering if people have any feedback or experience with release agents other then PVA? I’m thinking of going with a sealer, then semiperm and then with tr hightemp wax over top that.

The plug itself is smooth with automotive clear coat. I have tried a few small test areas and found that it release properly, I’m just a bit hesitant since I’ve only ever used pva…

Any tips and suggestions would be greatly appreciated.

On a side note, are semiperm release agents destroyed by contact with water? What would happen if I applied some pva over certain area coated with a semiperm?

#2

Semi perm is only used on the actual molds and not the plugs. Use paste wax (Meguirs molding wax) and if you are in doubt, then use PVA on top of that.

#3

Thanks werks, Will the tr high temp that I have not work? How is paste wax different?

#4

i had some results lately with wax on a painted auto part that really hurt my feelings… I had waxed the part at least 5-6 times but when i tried to demould it, the paint was unstuck from the surface and stuck inside the mold. i had to sand it ALL . and every time i pull a product out, some of the stuff unsticks from the mold and i gotta sand it again.

ANYWAY, that was a front spoiler…i had to do the back one too. I tried frekote , 4-5 layers, and did a test with polyester. it ate through the frekote, and through the clearcoat, paint, and primer (like the alien, it has resin for blood) …i did another test with epoxy and it worked perfect. so i went out and bought 1kg of epoxy mold resin, and used that (after yet another test) and made the mold with epoxy and glass fabrics. total cost = through the roof. but i expect it to be a perfect and REALLY strong mold (i’m demolding it tomorrow)

#5

Thanks aga, I appreciate your reply and I know what you are talking about I remember that thread.

I don’t intend on using poly resin, I only use epoxy resin.

So you had good results with the frekote and epoxy?

Please update on how the demold goes for you!

#6

Is the TR high temp a paste wax or what?

If the plug has fresh enamel paint on it, it takes a month or longer for it to fully dry / cure as it dries from the outside in.

#7

The paint and clear coat on the plug is years old.

The TR can doesn’t say paste wax on it…??? What is the diff between paste waxes?

#8

i guess he means paste wax or liquid wax…

i have liquid wax too, but they say its only good for silicone molds, or as a base for pva (priming wax)

#9

oh I see, the TR is in a tub… not liquid.

#10

i demolded the rear spoiler today, no problems at all with the release, it was more like a “wierd shape” and a “damn this clay” problem :rolleyes: …but nothing a few good kicks didnt solve.