Technical Any tips for removing back window with REALLY old/hard rubber? (1941 Buick)

I'm removing all the glass from my '41 Buick because we're getting ready to chop it. I cracked the windshield trying to separate it from the very original and very hard rubber gasket. No biggie because it's flat glass, but I don't want to do the same with the backlite. Any tips?
Thanks.
Curt

 

maybe some brake fluid , it destroys some rubber

 

Use a box cutter and cut the lip off of the rubber to expose the edge of the glass. You will need to buy new rubber anyway so just cut the glass out.

 

^^^ Break out the knife, save yourself a lot of grief.

 

I cut the glass out of my 51 Chevy a few weeks ago. I just cut the old rubber down to the pinch weld and the glass all but fell out. The rubber moulding was hard and brittle but it did cut ok.

 

Squirt some penetrating oil or any oil on it and let it soak before cutting.

 

Utility knife, cut around perimeter on out side , sometimes the glass will still stick to the inside face , score that area with said knife and ...viola..now...putting it back in is another technique by itself consisting of rope , soap and assistance of a dope....ha ha

 

i use a knife but tv shows use hammers. lol

 

when we would swop windows out of parts cars, to use the glass in the vehicle we would be saving. we would, break the glass to save the rubber on the project. cut the rubber on the donor to save the glass out of the parts vehicle.

 

I have removed a windshield from a 53 chev that had sat for years outside , I liberally loaded it with WD 40 and let it sit for just a few hours , damn thing slid out with very little effort .

 

...mite warm up the rubber with a butane torch very carefully, mite cut a lil easier

 

Or a heat gun.

 

heat gun and a knife is the way to go.

 

If the rubber is in any way pliable I use the box knife and a fresh blade, you want to swap out the blades often as the easiest way to get cut is to try to cut with a dull blade. If the rubber is really brittle I use a long-handed gasket scraper and a rubber mallet. You want to hit away from the center of the glass, not towards the center of the glass.

 

Thanks fellas. Worked like a charm. Took a while with two of us but the glass came out intact.

 

Great news there.

 

so which method did you use?

 

The box cutter is the only way to remove the glass, the petrified rubber isn't reusable anyway. HRP

 

The Buick glass is installed from the inside, so there's a rubber molding that captures the trim and the pinch-welded seam on the outside and the glass on the inside. I sprayed PB blaster around the rubber the day before, then @Cody Walls and I cut the rubber (outside of the perimeter of the glass) all the way around on the inside, then we slid a blade along the glass (running parallel to the glass) on the outside to break the bond with the rubber. It released pretty easily after that. Then we cut the top off the car.

 

That was pretty drastic punishment for the car for not letting go of the rear glass.

 

We don't take shit off anyone.

 

Make sure the glass can't fall inside and break when removing the rubber. I was not expecting that to happen.