We do a lot of etched glass vinyl designs on an Air Force base here in MS. The doors to many of the units have their Commander and Director of Operations names and ranks displayed on them. Every 1-2 years the personnel change and we have to change the names on the doors. We simply spray the glass with a solution of ammonia and water and scrape the old vinyl off with a single-edge razor blade. This is a technique I used years ago as a semi-professional window washer and it seems to work quite well. The ammonia-water solution helps to lubricate the surface to prevent scratching the glass. You just need to make sure you then clean the glass with something that is NOT ammonia-based since the ammonia will often degrade the adhesive of any vinyl you subsequently apply to the glass. We use RapidTac for that purpose. Let the window dry for a bit, then it is ready to accept the new vinyl.
Tim - Thanks for sharing that information. Ammonia sounds a lot less toxic than xylene, which I was thinking about using. We have used RapidTac and agree it does a great job prepping glass.
spray the vinyl with rapid tack and cover with a thin plastic film (like a garbage bag or something similar).
wait a while and it should just peel right off.
sorry if this was too late to help this time but it might help you next time ;)
I will try it next time. I used an ammonia/water solution on the 22" x 22" piece of etched glass film that needed removal. I can report that: 1) I didn't leave scratches on the glass and 2) my single-edge razor (and arm) got a good workout.
The first attachment is the film I had to remove and the second is the film I cut and applied.
I use a product called Vinyl Off by Crystaltek. Very little elbow grease needed.