So one fine day I go to my car and BAM rust on my A-pillar AND a cracked windshield. Naturally, I do what anyone else would and just soil my pants.
Took off the windshield and noticed more rust along the A - pillars and whatnot. I ground off most of the urethane and most of the rust (still have to get a good grinding wheel to get the rest off to get to clean sheet metal)

I'm not sure where to go next on this. I read I should just use POR-15 but I'm not sure if I need to use an etching primer underneath it or not. Not even sure if the new urethane that holds windshield on will stick to the POR15 as I've heard its pretty smooth.


Thanks for input!

 

Personally i would cut the rust out and patch the small area. It just looks to be very porous and thin. Usually caused by a not so good windsheild install in the past. Also if you do use por15 on it make sure it's topcoated. Por15 isn't UV stable and will break down. They offer top coats for it.

 

Thanks drag. If I do use por15, will I need some kind of primer? Or does it paint right on the bare metal. I was looking closely at the whole window frame (I'm going to probably at least primer the whole frame as there were small amounts of surface rust in random patches all over) and it looks like from the factory they put primer -> paint -> some kind of black layer over paint. Should I mimic that or will just putting por15 + top coat be good enough

 

Por15 in my experiences and from lots of reading on various different forums doesn't really like to adhere to bare clean metal. It's made to stick to rusty metal that is clean of loose scale. If u have access to a small spot type sandblaster you could sandblast the area and epoxy prime it then paint it. I am no definitive authority on automotive paint, but I have a uncle who does it for a living. I have picked up a few things here and there.

 

The black stuff i do beleive is the windsheild urethane adhesive. It needs to be completely cleaned off before a new windsheild can be "glued" in.

 

You should post a bigger picture of it.

 

you don't use anything under por15. Just make sure you clear coat it or put a top coat over the por15.

 

There is some recommended surface prep, but POR-15 is intended to be applied directly to bare metal- primer would defeat the purpose of using it in the first place.

 

I cleaned it up more since those pictures. Below is what it looks like now. Most of the black urethane is gone

Thanks. If I clear it will the windshield urethane stick to it?

Thanks!

 

I had a rusty windshield frame on a van and used rust convertor and let it dry and then had the windshield installed and didn't have an issue.