I have a bltouch clone which work fine on glass bed. After switching to textured PEI sheet, it’s variance trippled to 0.1mm, which make my bed mesh all wobbly.
I’m I suppose to remove the steel plate when making the bed mesh? Do you home Z with a probe with this setup?
The weirdest thing is, despite all this all my prints adhere completely fine. I guess PEI is just that good.
How are you checking your variance? Plugin on Octoprint or another way?
No, you should be running your bed mesh in whatever configuration you will be printing with. So if you’re about to print with your PEI sheet, run the bed mesh with the pei sheet installed. I have my start gcode set up to do run a bed mesh befre every print, if you’re interested I can help you with that.
It’s known that the rolled aluminum beds on cheap printers like enders are not flat, they all have waves in them. I’m thinking that the difference your seeing in the bed mesh variance between the glass built plate and the pei build plate is due to the fact that the glass is much flatter. The PEI will conform to some extent to the bed, which in turn will lead to higher variances. The bltouch is there to compensate for those waves in the bed.