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TTriton
06-14-2004, 08:16 PM
I have a question for anyone that might have some insight. OK.. I have painted many things over the past so I got a clue... But I have recently been listening to several differnt people about primer. I have heard some people say that you really need to have 100% coverage of primer and if you sand thou to the base coat in this case gel coat you need to reshoot the primer. Then others have said that in my case shooting over good gelcoat I don't even have to prime first just sand it down baby smooth and shoot the top coat which is a single stage paint. Any ideas??? suggestions???

Georgia Boy
06-14-2004, 10:39 PM
I am no expert either but from my experience I got better adhesion from shooting straight to gelcoat vs. shooting over primer. I am striping my boat for painting now and the places that I shot over the gel is alot harder to get off than the primed surfaces.~GB

WILDMAN
06-15-2004, 06:25 PM
I always sand with 400 grit, then spray the gel with a bondig clear, also called adhesion promoter. DO NOT sand any finer than 400 or you may have peeling problems

Georgia Boy
06-15-2004, 07:58 PM
I think that tells me what my problem is with my last paint job. I sanded and primed then wet sanded smooth with 600 grit and sprayed the color. it just kept bubbling and peeling off of the primer.

WILDMAN
06-15-2004, 08:49 PM
If it was bubbling up like paint stripper, That's because you probably used an enamel primer. Most basecoats will lift enamel primers.

Georgia Boy
06-15-2004, 09:55 PM
it was not lifting the primer, it seemed to be not adhereing to the primer. you could peel the paint up when i was stripping it and the primer coat looked good under it. I have never had that problem before. ~GB

SKATER241
06-16-2004, 08:08 AM
one of the best ways to ensure adhesion would be to use an epoxy primer as a sealer.a product like ppg dp 40 thinned down as as a sealer works best.this will also help with fisheyes from the fiberglass outgassing the release agent from the molding process.depending on what color you are shooting you really want full coverage of a sealer before shooting base coat to ensure no difference in color from primed or sealed area to an area that is gel.this is especially true when using lighter colors.

WILDMAN
06-16-2004, 08:52 AM
Yeah, what he said!

tabararacing
06-21-2004, 12:27 AM
I've used that PPG sealer stuff, its cool stuff, no doubt about that. I thought I'd pipe in, if you guys are ever doing mold stuff, I've found that duretec primer is the way to go instead of gel coat if you plan on painting it again. Sure stops pinholes and weighs significantly less than gel coat.
Brian