I have been printing with PETG on glass for a little while now, and have gone through almost an entire roll. Yesterday I had my first print stick so hard that it delaminated the glass :(. I stopped using hairspray as it made the prints not stick at all, and printing bare glass was just fine. But something about yesterdays print made the glass give up. Is this how PETG + Glass normally fails? Works perfectly for years, and then suddenly fails?
This does happen.
+1 for glue stick.
Also a layer of blue painters tape works well for me.
Another thing I've had good success with is cleaning the bed well with 95% IPA (thanks resin printing!) Then dropping the build plate with print attached into the freezer for a bit after it's done.
I used to do tape, but i really like the smooth finish that bare glass gives. Glue stick gave me bed adhesion issues, and i cant easily remove the glass bed.
I think the glass delaminated while it was cooling normally, not when i was prying it off.
Maker's Muse recently recommended G10 garolite as a durable print surface. This is basically a sheet of fiberglass fabric embedded in epoxy resin. It's cheap material, highly heat resistant and apparently releases prints very well.
I watched that video when it came out, but never made the connection to that being useful to me. I might give that a go when my replacement glass bed fails. Thanks!