This may be common knowledge, so I apologize if this has already been discussed.
In a nutshell … for Generic PLA, I can use the cold plate with no glue. I have changed the first layer height from z-0.04 to z+0.9 in the printer start gcode near the end where it tests for the PEI plate, and I select the PEI plate even tho I am using the cold plate.
After a couple of tall print failures (lift off) using the PEI plate, I decided to buy the cold plate and use glue. I was able to successfully finish my prints. But a friend had great success using an old surface he used to use on another printer and he simply raised the first layer so that it wouldn’t stick like super glue.
His surface looked a lot like my cold plate surface so I decided to give it a go.
It worked with great success !!
I can create different profiles for different levels of “stick” (-0.04 being the default PEI setting and WARNING! you might never be able to remove the print, and +0.9 where the print can be removed with a fair bit more effort than with the PEI plate. (wait for the plate to cool from 65 to room temp first)
Be aware that you may have to experiment with this setting with different filaments.
So now I use the PEI plate for general prints, and the cold plate with no glue for tougher models requiring more adhesion. Changing that number gives me control over the level of “stickiness”.
Note: I did use an old cold plate (used about 10 times) which I’d cleaned off all the glue with soapy water and then Isopropyl Alcohol so I believe the plate was completely cleaned of glue.
I suggest that you experiment with a small test object with an old cold plate first before committing a large print. If it doesn’t work for you, you might never be able to remove it, so experiment at your own risk !
A neater solution may be to remove the PEI code section and replace it with the “G9.1 Z+0.9” line of code, but it works fine as it is.