Windshield Frame Rust Repair?

stpete

Well-Known Member
Dec 26, 2015
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The windshield guy came to put a new windshield in my truck and we found that the previous install was pretty bad. There was rust around the edge of the windshield and was spreading. The windshield is out and I have gotten the frame to bare metal with a wire wheel. There rust was just surface with just a few spots that are starting to pit. But, I still have the black rust stains that I know can come right back. I think if I try to grind them completely away I might weaken the frame as they are in the corner.
I'm trying to get this done in a short amount of time. Is there a specific primer or product I spray before primer that would help keep the rust from coming back. Preferably something I can get pretty easily that's either rattle can or brush on.
 
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It turns the rust black, you can see all the little spots were the rust was. It was really rusty behind the hinges and that whole area turned black.
0oYP5wrSrUgQPMKiQxb1lHowPOLNDp1WVnIZvBNi1npLtxy4AqJdZ0rPVlgvn14ITSFKconAUCYjAL7yat9KmmZN2kYK4RSeFeeM8QALCLVcl7YYm5wT81_FYl9o3ZZ9BwkFsbtG8q0yyDza72QxRAYfzEwtIkcHbate26wLgtYEi4WT5-jENNwLnFGrrcdNEOF3-XEmy5f6hRmombxBQGFfYwW-rlWs2iNIljWWtW0FFS9FPoEbgNyCBjR8FjK3oPGRxFK1mCvf2D_VnLNeul3rSb4Srt4Eh65oMJa2epX__mLe8YkHdrNyB19bXX-I_PzTIa2ZdpkDscUcAo_6uJ8B5V4Zyfr97EG0IWSX8p2Lz_ubM_yIvNsQceyS_rdjJLYpz0dQl2v4KJJL_Y1dvJnyDkRi8M3uE3Hr0rj2zUrHR2xRpIDwcH-bdLi-PUIoK6MYNx5a1LVN-xMW_nLTJB8dSdL9Qm6l-xScrvgOx3fK0G23wFPLAPG7DHoNE5tp1oyZEuVt48evVCnC0o_HX6qYuurbFAU8fksWt3rcn8JQ1Pg58ybzYxc6flQWFpzhtTAupv3yXT7FrnvAi3E7Gv6mupJIIG0zcKnJNcXNKA=w1687-h1265-no
 
Phosphoric acid solution. It's what we used at Safelite to get rid of as much rust as possible. We also used specific primers that wouldn't affect the bonding of polyurethane window adhesive. The primers were made by Dow or Sika, I don't remember which ones anymore. Do not use body filler in the pinchweld areas where the glass sits.
 
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I wish I knew of a place to grab ospho last night. I got a similar phosphoric acid based rust converter from the local auto parts place(I think made by loctite) last night and brushed it onto the rusty areas. Hopefully it works similarly enough and stops the spread. All the rust did turn dark black.
My current plan is to use an etching primer next since I have some bare metal, then sealing primer, then some duplicolor Oxford White and maybe some clear. If all goes well, I will be ready for a windshield on Monday. It will be nice to get that back on the road.
 
@Davedacarpainter This is the worst area. It's a little hard to tell from the pic because it's already been "rust converted". I had hit it with a wire wheel and smoothed it out. It was still brown at this area, but most of it was black staining with no pitting.

2622.jpg
 
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@Davedacarpainter This is the worst area. It's a little hard to tell from the pic because it's already been "rust converted". I had hit it with a wire wheel and smoothed it out. It was still brown at this area, but most of it was black staining with no pitting.

2622.jpg
I don't see that it's rotted:nice:.

The rust converter will only go so deep into you rust before it dries and the chemicals loose their ability to convert the rust. You will want to sand it all down and reapply the converter to those areas that are still rusted.

On the bare metal you'll want to use an etch primer or an epoxy primer. Though i wouldn't use an epoxy in this situation since the converter uses an acid to convert the rust. Acid and epoxies don't go together.

Have you thought of using a small hand held sandblaster to finish cleaning out the rust?
 
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Why couldn't the windshield installer do the repairs on that for you and install the glass? I've done it hundreds of times. If there aren't any holes, and the rust isn't too bad (which it looks like it isn't) we would treat it, prime it, and complete the job.

In the future, if you have glass replaced, and the guy used a pipe knife or cold knife to remove the glass, make darn sure he seals the scratches back up with primer and sealer. There's a reason some glass companies charge more to do an install. If that was done by Safelite, they would pay for the repairs. Lifetime warranty on glass breakage not caused by impacts, and on the install quality.
 
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I don't see that it's rotted:nice:.

The rust converter will only go so deep into you rust before it dries and the chemicals loose their ability to convert the rust. You will want to sand it all down and reapply the converter to those areas that are still rusted.

On the bare metal you'll want to use an etch primer or an epoxy primer. Though i wouldn't use an epoxy in this situation since the converter uses an acid to convert the rust. Acid and epoxies don't go together.

Have you thought of using a small hand held sandblaster to finish cleaning out the rust?

Well, I'm thinking about it now. I found a cheapo HF one I can borrow today. Still puts me behind my desired schedule :bang:

But, I prefer to do it right. I think it will be up to the guy with the garage it's in how much longer I'm welcome :rolleyes:
 
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Why couldn't the windshield installer do the repairs on that for you and install the glass? I've done it hundreds of times. If there aren't any holes, and the rust isn't too bad (which it looks like it isn't) we would treat it, prime it, and complete the job.

In the future, if you have glass replaced, and the guy used a pipe knife or cold knife to remove the glass, make darn sure he seals the scratches back up with primer and sealer. There's a reason some glass companies charge more to do an install. If that was done by Safelite, they would pay for the repairs. Lifetime warranty on glass breakage not caused by impacts, and on the install quality.

It looked worse than it wound up being. I didn't have the installer take the glass out because I had to arrange a place to do the work if it was rusted through. The rust was going under the adhesive in multiple places. Fortunately, it's better than I expected. I was expecting to have to take it to a body shop to get some metal work done. I discussed the options with the glass installer and felt like I was better off taking care of the problem as opposed to having a truck with no windshield sitting in my driveway. I'm not sure how well the installer treatment works, but I'm hoping to do better.

I bought this truck off the internet. I wouldn't have bought it if I had seen it in person. I would love to kick the previous owner in the nards repeatedly for all the stupid s*&t they did. The headlights were wired with speaker wire. It took me $3K in parts and about 100 hrs of my time just to get the thing through a MD inspection and get it registered. I'm not sure what the PO used to remove the windshield, but it might have been a hatchet. There isn't a 2" stretch around the perimeter that wasn't gouged enough to have a little rust forming. I have a cold knife and have used it in the past. Didn't work on this thing. There was adhesive glopping out both sides of the windshield. The glue line was as wide as it could possibly be in most spots. It was hell getting it out. I'm not surprised, but it is another kick in the area if anyone ever walks up and says "Hey, that's my old truck".:cool:
 
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Blasted the frame. It came out pretty good except this one spot. @Davedacarpainter, what should I do about these? Can I just fill them, or do I need to break out a welder?

HolesinWindshieldFrame.jpg
The problem there are the tiny little holes that go all the way through the metal (I would say penetrate, but, you know, the guys here:nonono:).

It means the rust will be on the backside as well. Plus the metal will probably be too thin there because of the rust.

You would probably blow holes through it if the welds would stick at all.

It’s not too tough to fix, just a little cutting, fabrication of a new strip of metal, etc.
 
The problem there are the tiny little holes that go all the way through the metal (I would say penetrate, but, you know, the guys here:nonono:).

It means the rust will be on the backside as well. Plus the metal will probably be too thin there because of the rust.

You would probably blow holes through it if the welds would stick at all.

It’s not too tough to fix, just a little cutting, fabrication of a new strip of metal, etc.

Yeah, I was worried about welding that. Especially with the welding skill level I have available to me. I don't think I'll quite be able/have time to fabricate a replacement part, but I'll paint some rust converter on the underside and fill the holes with something. JB Weld?
 
Use an encapsulator for the backside. If you need to drill out one of the rusted through holes a bit to stick a painting wand in to coat it, that’s what I would do if i wasn’t going to cut the rot out.

Any heavy duty epoxy to fill the holes like jb weld or a panel bonding adhesive.

It won’t fix it for ever, but probably good for ten years though.

I just want to stress the importance of coating the back side with something that’ll seal it up, like POR15 or some such product.

Have you pulled the headliner away from the roof there to take a look at the backside?
 
I looked at the backside today. Problem is, there's another layer of metal under the parts with the holes. I filled it with the JB weld steelstick. I created a 2" long section to try and make sure it stays intact. I can tell my welcome is wearing thin at my buddy's garage, so gotta get it done.

It's got 2 coats of etching primer, 2 coats of sealing primer, and 2 coats of Duplicolor on it right now. I have a couple spots where the tape tore up some paint that I need to fix and then add a coat or two of clear. Hopefully that'll do it and I won't have to deal with this again as long as I own it. I didn't think blue tape would rip the paint underneath up, but it did. I don't think the new blue tape is the same as the old. It rips up the paint under it, but won't stick to the paper or itself. Stuff sucks.
 
I looked at the backside today. Problem is, there's another layer of metal under the parts with the holes. I filled it with the JB weld steelstick. I created a 2" long section to try and make sure it stays intact. I can tell my welcome is wearing thin at my buddy's garage, so gotta get it done.

It's got 2 coats of etching primer, 2 coats of sealing primer, and 2 coats of Duplicolor on it right now. I have a couple spots where the tape tore up some paint that I need to fix and then add a coat or two of clear. Hopefully that'll do it and I won't have to deal with this again as long as I own it. I didn't think blue tape would rip the paint underneath up, but it did. I don't think the new blue tape is the same as the old. It rips up the paint under it, but won't stick to the paper or itself. Stuff sucks.
Blue tape is for house paint. I use the 3M yellow at work.

It's more porous than the yellow, it allows the paint to soak into it. It works fine for house paint since it is much thicker. Automotive paint is so thin, it soaks it up.
 
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Just to follow up and end the thread. I got the windshield in the day before Thanksgiving and used the truck for a little Thanksgiving travel. It was a bit of a last minute flail to make it happen. I tried to hurry the process by painting coats to thick and not waiting long enough between coats with bad results. I spent the day Monday driving back and forth between work and my buddies garage every couple hours and recoating parts of the roof to get good protective layers in place. It's definitely a 10-20' job, but it's done and should provide a good sealing layer to prevent future outbreaks. I have 2 coats of etching primer/sanded/one coat of sealing primer/feathered edges/3 light coats of white were needed to completely obscure the primer/2 coats of clear. It had about 30hrs to dry before the windshield installer got there. At least 2 hrs between coats. Trying to push it to less than 1hr between coats led to spots peeling.
Thanks for the advice. I'm more confident this will last than I would've been by sealing the rust only.
PaintedWindshieldFrame.jpg
 
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