Coreforge
Member
I've had good experience with PVA on glass. I just coat my print bed with watered down PVA glue every few prints (you can see if it came of in some places as the surface will look shiny instead of matt), let it dry and make sure my first layer adheres well. My print bed isn't really calibrated at all (just some leveling by eye, it literally is two sheets of glass from scanners on top of a cheap wooden board), so I have some variance in height, but as long as the first layer isn't too thick, it should work. It should always be a solid layer without random gaps, but in my experience it's fine if you can kinda see through it, although that is pretty thin. I really had to work some prints off as they nearly adheared too well. I've only tested this with PLA, but it should work with PETG as well, even if maybe not as well, since it leaves a slightly rough surface.
