Talk Composites - The Forum for Advanced Composites

PVA release agent - how long before applying epoxy gelcoat?

http://www.talkcomposites.com/Topic22478.aspx

By Christian_83 - 12/25/2016 3:44:52 PM

Hi Guys
Im trying to make a mold of an existing part /that i use as a plug)
Ive given the part 5 times of carnauba wax and then 2 coats of PVA (20 min cure between layer) I didn't have the time to put on the epoxy tooling gelcoat. 
So my question is, will the PVA still "work" if i put on the epoxy tooling gel coat in 24 hours? or will i need to put on new PVA?
Is there any reason with applying more than one layer of PVA (to be sure that all corners and fed ) ?

Cheers
Christian
By Hanaldo - 12/26/2016 1:33:00 AM

No time limit as such, you just want to apply it before it gets covered in dust or other possible contamination, and beware of the PVA shrinking in places and cracking or pulling away from the surface. 

Other than that, you could apply the gelcoat 6 months later and it wouldn't be a problem.