I have 2 Prusa i3 mk3. They have a special metalsheet that is coated with PEI i think it's called. I previosly used a gluestick, but that stopped working. So i cleaned the sheet from all the glue and now i really find that it works best when i just clean it with alcohol. Nothing is coming of during the print. But the glue hardend and actually made it worse.
So for me it works best, when just cleaning with alcohol.
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