Working with Original Glass
If you’re doing a concours-quality car, saving or scrounging decent original glass will be essential. And even if you aren’t, because replacement glass is expensive, and if the glass on your car is still intact, you’ll probably want to try to re-use it. At least that’s been my orientation so far. The windshield will be replaced with a new (modern, not repro) Carlite-branded winshield from NPD, but I’m trying to save as much as possible of the side and rear glass.
The problem is, my car sat outside for 35+ years. So not only is there a thick layer of much on every piece of original glass (both on the outside AND the inside), but the junk on the outside was baked into the glass by the sun for an eternity in car time. The windows are heavily water-spotted, but the biggest issue is the hard layer of tartar that somehow built up around the edges. Nothing easily removes it.
I started by washing down the windows inside and out with dish soap, water, and a non-scratch scrub sponge (do NOT use 3M yellow sponges with the green scrubby side— they WILL scratch your glass according to the wisdom of the internet— but the blue/blue ones worked fine for me). From there, I dried off the glass and tried using window cleaner to see how much more there was to do. At first it looked like I’d made some serious progress, but as the last moisture evaporated, I was left again with a dull satin surface instead of the clear shiny glass I’d hoped for. Next I tried Bon Ami, which seemed to make a small improvement (I ignored the instructions and used the current formula with the limestone in it, even though Bon Ami Original formula is the only one you’re supposed to use on glass). I tried rubbing compound, which did nothing. Lacquer thinner was no help, either. The only thing that seemed to make any real difference on the ring of garbage on the edges was 0000 steel wool, but that took forever.
Having found nothing that really worked quickly, I resigned myself to use the steel wool. Cleaning just the two small sheets of glass in the vent windows took three hours of repetitive scrubbing, it was deadly dull and boring. Without the patience or the room to sit and scrub the main side windows, I eventually tried using the rubbing compound and the 0000 steel wool together, which sped things up a bit. Not perfect, but good enough for me. And having spent an hour fussing with the vent window glass trying to get it to re-seat in the frame, I also decided the polish on the main window frames was good enough as well. No need to pull the frame off and go through the hassle of re-seating the glass, it’s not worth it. If I ever decide to turn the car into a concours car (doubtful, but not impossible given that I’ve saved every part that came off and have used concours-quality hardware wherever possible), THEN I’ll pull the frames out and polish everything up. For now, and in the interest of progress, I’ll stick with what I’ve got.