!! Problem with release agent PVA !!

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!! Problem with release agent PVA !!

Author	Message
Evripidis	Evripidis posted 11 Years Ago HOT Topic Details
Group: Forum Members Posts: 5, Visits: 23	Hi I have a problem with the application of pva. When i apply pva with the brush, it shrinks, it can not stay at the place where i suffuse it and as a result there are areas with no pva. I thought it was because of moisture and i try to heat the glass with an airgun but the results were the same. Pva is applied on a glass surface. I want to point out that i was following this procedure and everything was ok. This is the first time that i have problem with the pva. I don't know where the problem comes from. Could anybody help me? Thanks in advance
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Hanaldo	Hanaldo posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	2 things. 1. It sounds like you're applying way too much PVA. When there's too much I've found it does tend to fisheye quite a lot. My best results with PVA, aside from spraying it, have been with using a soft cloth to wipe on a very thin film. Juuust so that you can see it leave a wet mark on the part, but not so much that you can actually see the colour of the PVA or a raised surface. PVA will work with a very tiny amount, and the less you use the better your surface finish will be. 2. Have you tried letting the PVA start to dry, then giving it a quick wipe all over? The PVA will start to form a film and go a bit tacky, so when it does this you can brush over the fisheyes and then it won't spring back again.
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Evripidis	Evripidis posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 5, Visits: 23	Thank you, I ll give another try
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Hanaldo	Hanaldo posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I do recommend spraying though. If you've got a compressor then just get a cheap gun to spray it with. Clean up is as simple as putting water in the cup and spraying it out. Otherwise if you haven't got a compressor, I had good results using a Preval spray system before I got my gun.
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