Auto Glass: Pinch Weld Prep, Pinchweld Prep, Primer

Question
Hi, I have a Jeep Cherokee undergoing complete restoration. It's stripped down to just the body. I removed the old windshield, and cleaned all the urethane and surface rust off of the pinch weld, and sanded it smooth. It's down to the factory primer with some bare metal showing. I'm spraying the entire truck with POR-15 paint. Is it safe to spray the pinch weld too? Or will that cause the urethane to not bond correctly when I put the new glass in? What do you recommend? Thanks, -Chris

Answer
Hi Chris!
           I do not know much about paint but I will try to help the best I can.  Having said that,I want to say NO to the POR-15 paint on your pinchweld,and here is why :  Do we know if the POR-15 paint can hold the 500-1200 Psi needed to hold the glass in? If the Paint CAN tells us this then OK? But Even the Big Three have had Paint Problems. I will give you an example, A Very popular Truck Manufacturer (I will not say there name here :) who have spend millions on Research over the years put out a series of Vans from 1999-03 that had Paint failure. After removing the Windshield You could actually pull the urethane and paint off the pinchweld all at once with very little effort. Was it the paint? Bad Glue? Climate? Who knows. One thing is sure if the paint that is holding the Urethane can not hold to the cars pinchweld, what holds the Glass? Scary no? Do not Paint!!!  Without being there and looking at your car I would say If you get it clean enough that your down to the metal with no rust then a good coat of Urethane primer should be fine! If your still not sure you can always call in a Pro to look at it for you. But make sure he is not a rookie, That's probably how the rust got there in the first place LOL :) Also Remember! All Urethane Applications require primer both Glass and Pinchwelds. Hope this helps! Let me know how She comes out!!
                                             Derek :)