How can I get a rear view mirror button off the windshield if it was put on upside down?
Applying heat to one side, interior, of a vehicles windscreen runs the very real risk of cracking the windscreen, because of the differances in expansion. The more usual way to remove a stuck on mirror is too use a length of wire. Introduce the wire under one corner of the mirror and pull it side to side to cut through the adhesive and any patch used. Finish off by cleaning off any residue adhesive. This is the same method used by professional outfits to remove whole bonded windscreens when they are too be re-used. Using heat is is a very risky business unless you are able to control the temperature of the whole screen and should only be considered as alast resort.
I found these instructions on eHow:
- Use the blow dryer or heat gun to warm the mirror mount right where it attaches to the windshield. You are applying this heat to soften the adhesive underneath.
- Test the mirror every so often while you are heating it by trying to gently move the mirror slightly back and forth. Once you feel movement, continue to apply heat and increase the force a little at a time. Work the mirror back and forth and it will release from the windshield, leaving a fair amount of adhesive behind.
- Warm the adhesive left on the windshield again. For thick patches of adhesive, wrap the fishing line around your fingers as if you were getting ready to use dental floss and press your fingers up tight against the windshield on either side of the remaining adhesive. Work the line under the top edge, and move the line back and forth with downward pressure. The line will cut through the adhesive and remove all but a little residue.
- Apply the adhesive remover to the residue and use the razor scraper to gently scrape off the rest of the adhesive. Wipe the area with a rag and more adhesive remover.
- Clean the area with glass cleaner.
These look fairly comprehensive. You may want to put the mirror on the mount, even though it's upside down, so as to have something to hold on to. Do not apply too much force to it, though, as you run the risk of breaking it. Also, ensure you remove all of the glue off of the mount, as new glue will not want to stick to it if you don't.
They actually sell a debonding agent just for that very purpose. As I recall, it sprays on & wicks under the button, releasing the button.
But... the SIMPLE thing to do, and least worrisome, is to get another button and stick it directly to the one that's already in there... only right-side-up this time. Nobody will ever notice that you have two buttons, one stuck atop the other. I've watched a good mechanic do that in a Porsche dealership.
I was able to get mine off using floss. It fits into the gap between the windshield and the glued on metal button better than wire. You have to keep at it and use several pieces of floss since the floss will break. It took me about 10 minutes. Floss is thinner than most wires and fits into the narrow gap well.
I tried the dental floss and it wanted to cut into my hand holding it taught. I then used a disposable lighter, paying attention to only letting the flame touch the metal mount part, with the mirror removed (I shattered a windshield once directing flame into the glass). 10 or 15 seconds, a couple times, and it popped right off with pliers!
The wrench trick did it for me. Carefully applied pressure with a long handled wrench and just when I thought it wasn't going to work-pop! No damage to the glass, either. The hardest part was finding the button after it popped off. It ended up under the passenger side seat almost under the rails.
I just now accidentally glued the button on upside down. Here's how I fixed it. I attached the mirror to the upsidedown button and then pried it off. Then with a very flat screwdriver I scraped everything off the window and the button, and used glass cleaner to clean both pieces. I just glue the button back on right side up, fingers crossed it's sticks.