PEI Print Bed Question

Hey Guys,

I have done a lot of digging on good ways to adhear ABS to the bed. I have attempted every possibility and never had great success. I ran into PEI and ordered a sheet and absolutly love it! I find that it doesnt stick as well as others have reported, but If I print with a brim at 115 degress on the print bed, it never lifts. So that is still a win! Not to mention the bottom layer has a very sexy matte finish

However, I am starting to think back on things and I think the whole issue I have been having trying to find a good way to adhear ABS is related to extremly thick glass I have, I think it is 3/16 or thicker (came with the printer, and I bought it from Craigslist.) I have always allowed the bed to heat for about 20 minutes before starting to print, due to the thickness. However, I am starting to wonder, due to the thickness, am I seeing much lower surface heat compared to what the thermistor is reporting?

So my questions is, Can I glue the PEI directly to the PCB board? This will allow for direct heat transfer to the part, faster warm up times, and potentially allow me to lower the heated bed temp. I understand that this means that if the PCB takes a crap, I gotta replace the PEI as well, this is minor for me as I just want to be able to print ABS flawlessly. I also realize that this means I will not be able to have multiple print beds for easy change outs, however I dont have that now and do not have the need/desire to do so.

If you feel that this isnt a viable option, what would you suggest to use instead of the thick glass I currently have, i have a 12"x12" bed