The Stovebolt Site Forums The Shop Area Paint and Body Shop Primer preference?

Prior to installing a windshield, once the track is cleaned out and wiped down. With about 25% bare metal showing, what would be a preferred primer to spray for the installation of a windshield?

I'd use epoxy primer. You can get a rattle can with 2-part epoxy in it. They have a button on the bottom to push and activate it. I think they're about $20-25 each.

I would also suggest the epoxy primer but would go a step further and finish the hidden area with a good topcoat. The primer alone is not a waterproof coating and in the very vulnerable metal under the gasket it will absorb moisture if not sealed with a finish coat. I would use an acrylic enamel or acrylic urethane and match the primer to it.

Kevin is correct, epoxy primer is waterproof once fully cured. Thus the reason the industry recommends it after sandblasting or striping down to bare metal, sealing the metal from the elements.
Other primers such as high build urethane, polyester or lacquer are porous and must be top coated.

Thank you, I stand corrected.

So now, are we saying we don't need a top coat over the epoxy primer prior to installing the windshield?

From the comments and a little reading on the innerweb, you may be fine with just the epoxy primer.

I would top coat any form of primer.

I would also topcoat all areas before gaskets and weatherstriping are installed.

The rattle can epoxy primer I have used has a matte finish (kind of powdery), so if that was used, I would definitely top coat it. It is handy for spot primering though, rather than pulling out the spray gun and mixing a little bit of 2-part epoxy, although in a concealed space like under weaatherstripping, it could be brushed on.

Yep. I recently did 2 windshields. I would say just one top coat.

One top coat no primer, not really sure which way to go here now? Some say epoxy primer no top coat, and some say epoxy primer with top coat.Would a base coat clear coat be sufficient for a top coat? Thank you..

Bare steel needs a primer coat, and typically a primer coat needs a top coat. Just a top coat probably won't adhere adequately to the bare metal. Clear coat could be used as a top coat over epoxy primer.

Remember now this is just for a windshield install, I plan to paint the car later. Not really worried about painting the car with the windshields and side windows in or not.. The car is not really a nice piece at all, so I am not to worried about it..

The epoxy is adequate for preventing rust under the windshield gasket so you can just leave it as is until you’re ready to paint. The preference would be to apply a top coat to add UV protection to the epoxy and if your masking wasn’t perfect when you do get around to painting, there would be color where you missed. It’s really important when you do paint, to sand the area next to the rubber really well to get proper adhesion to the epoxy or the paint will be prone to chipping.

You can use the paint of your choice on top of the epoxy, base coat/clear coat or single stage.

Would there be a problem painting the whole car epoxy primer and leave it like that.. I guess they call that a patina look?

I rattled canned this truck and keep in a barn. I did this to see any imperfections. Cost me less than $100.
Ill fix the spots and spray again. I might leave it so the next owner can paint it whatever.

Hey there Ol'55 , you've gotten a lot of good advice in the previous posts. What you are being advised to do is after you've prepped the area ( clean, free of oils, etc..sanded with 220 -320 grit) , lay down a couple of wet coats of 2k Epoxy primer and be sure to follow the flash times between coats. Once your epoxy primer has cured (follow the application instructions guidance) you should apply a top coat ( I'd go with a single, stage acrylic black paint ) that will be compatable with whatever finish coat you plan to apply later on. There is usually a "window" of time where you can apply the "top coat" directly to the epoxy primed surface, usually within 24 hours. Why is a top coat recommended? Because the epoxy coat is not resistant to the sunlight ( UV rays ). If you use black you'll only need to scotch brite what's outside the windhield gasket, tape it off and spray your finish coat once you've gotten to the point that your ready to do a "paint job". If you decide to paint the whole "truck" in epoxy, forget the acrylic paint recommendation. Just leave it alone and then when you epoxy the whole truck you'll need to do a satin clear coat over the epoxy. If you going to do that ( whole truck in epoxy ) I'd recommend you stay with one brand of product so that compatability isn't an issue.

This is epoxy, no top coat. When left in the sun, the epoxy will start to chalk. That's, maybe, 10 years of weathered epoxy in the picture.

Most of my experience is with Southern Polyurethanes (SPI) epoxy, whose properties may not translate exactly across the board to other epoxies.. With SPI epoxy it is waterproof after three coats. One doesn't normally spray that many coats on a windshield opening, and to resist any risk of chalking from UV exposure, I'd say your best bet is to media blast any pitted/rusty areas and address repairs as needed, epoxy prime, and then topcoat. (observing all mfr recommended flash/recoat times)