Currently, my print bed has PEI that is bonded to glass. While I can remove the glass with the PEI from the print bed as that is just resting on a silicone thermal pad, I can’t remove the PEI itself from the Glass since it’s bonded to it using 3M double-sided Thermal Tape.

This is a problem now because I want to start trying to print with PETG… and that stuff is crazy-sticky. From my understanding printing it on PEI is not a good idea because it will pretty much bond to it, in fact, even on bare glass without some kind of coating it’s still not a good idea as it can even stick to the glass too well and damage it… as shown at the 3:20 mark here:

I also don’t have a spare piece of glass to use without the PEI, and even if I did, that would mean I would have to re-level the print bed every time I switched between the glass alone or the glass with PEI on it as they are different heights…

I figured, maybe I could temporarily just put some blue tape on the PEI itself simply so the PEI would not be printing straight onto either PEI or Glass.

But I have a few questions about this:

First of all, does PETG even print well on Blue Tape?

And if so… does it also print “too well” and it would just get stuck to the tape?

Would it even ooze through the tape and get stuck to my PEI anyway?

And finally, if it would work fine… is Blue Tape safe to use on PEI? Would it leave any residue or somehow damage it for printing with PLA or other materials?

I have a Prusa Mk3 with PEI bed. I print PETG often with no over-adhesion problems. I use the Prusa recommended Windex on the PEI bed to reduce adhesion.

I have an MK2 with PEI and print a lot of PETG.
Windex, original one, is an option.
Set you first layer so it isn’t jammed into the bed. Go with a first layer height of 110-120% which will help to reduce the adhesion also.
It will take some time to figure out when to try to remove the print also.

I remove mine while it is still cooling. I think once I get to 45c or so on the bed temp but do not force it.

Just because…could you flip the PEI-on-glass over and use the glass side up?