Vinylester over vinyl?

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#1

Hi,

here is a probably stupid question.
Will vinylester gelcoat stick to vinyl?
I have a mould that has some voids on the barriers and i need to make a split mould so adding another coat of gelcoat above this one will make it crack or stick to the bottom part. I had a (probably stupid) idea of wrapping the bottom mould with vinyl (vinyl for making stickers) apply release agent and make the top mould on that.
Will it stick or can i get away with that?
Imagine you have a vinyl wrapped car hood and you what to make a mould without removing the wrap. Is it possible?
Thanks!

#2

TEst, test, test.

The styrene in vinylester can attack the glue layer, creating havoc with the vinyl.

I would certainly make a test, and probably accept the use of PVA release agent, which can act as a styrene barrier.

Also mix your gelcoat relatively “hot” or fast, to prevent a long time styrene attack.

#3

but the glue is under the vinyl. Will it pass through the vinyl layer and get to the glue?

Thanks!

#4

Styrene is a strong solvent, and has the tendency to go through about everything. I would not be surprised if it went through vinyl as well.

#5

even if i use a release agent over the vinyl? will it go over that? i don´t need a perfect finish as i will only cover the barriers, but i don´t want it to stick