Primer For Quarter Window Repair

boostfrk

10 Year Member
Aug 30, 2011
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Colorado
I'm going to repair my quarter windows this week while they're out and the car is getting painted. I've read lots of information about repairing these, and people usually mention a high-build primer (Duplicolor) or sometimes specifically SEM's flexible primer surfacer to fill in the pits and roughness associated with decrepid quarter windows.

Is a flexible primer required, or are people just buying SEM because of the quality of the product? Has anyone here used a standard high build primer like Duplicolor?

How many cans of primer are people typically using to fill in the pits and get the molding smooth again?
 
I actually used 3M windshield eurathane to repair a set once. Turned out excellent. Just cleaned them up really well with some thinner, scuffed the area with some sandpaper and spread it on with my finger. Block sand when dry, prime and paint with some matte finish. Dried hard, but still had a flexible texture. Primed it afterwards and painted. They were good as new.
 
I used Duplicolor high build primer and semi gloss black paint. Mine look like new now.

Chris

I'm using the same primer and then Duplicolor's Trim Paint. The driver's window is done and I'm working on the passenger window now. Biggest issue is some of the rubber peeled off on the "front" of the window (facing the front of the car) right where the rubber met the glass. I've got it taped off so I can create a straight line but I'm not sure I'll be able to build the primer up thick enough to match the thickness of the rubber. It may take 20 coats or some crap.
 
As I think I mentioned before the passenger side window was in bad shape. A decent amount of the rubber had peeled off on the "front" of the window (the edge that faces the front of the car). I taped off the line where this rubber should extend to, and started shooting coats of filler primer. I'm still nervous how it's going to hold up but it's better than what was there before. Paint, sand, paint, sand, paint, sand, paint, sand, etc. nearly all day yesterday.

I've finally got this portion of the molding built back up to look like it should be. The primer was getting so heavy that I couldn't see the tape line anymore, so I removed the tape, cleaned up the edge, and then laid down new strips of tape in order to finish off the remaining coats of primer. You can see a blemish at the bottom and the top I'm still trying to get perfect. Hopefully I'll be painting these windows over the weekend.

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Before I cleaned the edge up.
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I'm telling you guys....don't bother fudging around with primer that's just going to peel off over time, or the first time you blast them with the hose. Primer is only good for a few coats. 3M windshield urathane is what you want. Spread it on with your finger, let it dry and block sand it smooth. You can lightly prime and paint it afterwards.
 
I'm telling you guys....don't bother fudging around with primer that's just going to peel off over time, or the first time you blast them with the hose. Primer is only good for a few coats. 3M windshield urathane is what you want. Spread it on with your finger, let it dry and block sand it smooth. You can lightly prime and paint it afterwards.

Are you talking about this stuff, Brian?

http://www.amazon.com/dp/B000RW1XCK/?tag=stangnet-20
 
Don't fix them on the car, you'll end up cracking whatever product you use to fix them IF you ever go to pull them out in the future. Pull them, fix them on a work bench.

I will say, the 1st car I did I was 21 and I used 2 cans of spray bomb primer, trim black and no clear coat. The moldings developed TINY TINY bubbles. I assume it's because they weren't sealed off.

Pictured below is the 2nd set I did. Sand, Nason 2k Urethane primer...basically only two coats because it's a professional prodcut, lots more sanding, then trim black and low luster clear coat. These held up great. The 3rd set I did I used teh same method and got the same result.

From 2008
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My yellow car from 2008
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Don't fix them on the car, you'll end up cracking whatever product you use to fix them IF you ever go to pull them out in the future. Pull them, fix them on a work bench.

I will say, the 1st car I did I was 21 and I used 2 cans of spray bomb primer, trim black and no clear coat. The moldings developed TINY TINY bubbles. I assume it's because they weren't sealed off.

Pictured below is the 2nd set I did. Sand, Nason 2k Urethane primer...basically only two coats because it's a professional prodcut, lots more sanding, then trim black and low luster clear coat. These held up great. The 3rd set I did I used teh same method and got the same result.

I took them off the car; since the car is out at paint I had to pull them anyways.

I just laid the first 2 coats of trim black this morning. I wasn't planning to use a clear as most people I've heard don't use a clear with the trim black paint. How quickly did the tiny bubbles form?
 
It didn't take long. This was in 2004, so IIRC I refinished the quarter moldings around December, and I noticed bubbles by March. They had plenty of time to dry obviously because I have a shop. The car sat outside in my driveway for about 3 months. It saw cold temps and snow. That might have had something to do with it, but regardless....water/moisture isn't gonna be good.

Get yourself some low luster clear to seal it up and you're good. It doesn't shine it up like regular clear coat on your actual car. It just seals it off from the elements.

I had 2nd and 3rd cars for a long time (had clearcoat) and they never lifted or bubbled. I sold the red car to a good friend over a year ago. I saw it last Tuesday and it's still like new.
 
Any idea if the Duplicolor Trim Black is a laquer or enamel paint? I believe it's a laquer since it doesn't have a recoat window, but want to make sure and get the right kind of clear to spray over it.
 
I think it's a laquer too. I just made sure I bought the same brand of both products. If you look into SEM they have their own trim black and they also have 3 different clear coats. The low luster, the medium luster and the high gloss. Duplicolor has their line of clearcoats, never looked hard enough to see if they have different lusters but honestly....those rattle can clears aren't going to shine up your car like a professional clearcoat will on a body panel.
 
Thanks. I'm not too concerned about the gloss associated with the clearcoat as I figured I could find a low luster, but more so because I haven't heard of hardly anyone using a clearcoat after re-finishing their quarter windows, or any other trim parts for that fact.

I don't want to leave the clear off and have the same problem you did, nor do I want to put it on and have some other unforseen issues.
 
Thanks. I'm not too concerned about the gloss associated with the clearcoat as I figured I could find a low luster, but more so because I haven't heard of hardly anyone using a clearcoat after re-finishing their quarter windows, or any other trim parts for that fact.

I don't want to leave the clear off and have the same problem you did, nor do I want to put it on and have some other unforseen issues.

Yeah, just stick with the same type of paint and even the same brand. You only need a couple light/medium coats.

If you wanna test it out, just spray a scrap piece or spare piece of plastic you have.