Clear PETG printing adhesion issues
I have an Prusa MK3. I am having problems with adhesion, separating, and lift/bubbling when printing a first layer. Most prints are fine with other types of filament but not the clear PETG. I am using Overture. I have tried many adjustments with fan speed and extruder, etc., to no avail. See pictures. 
RE: Clear PETG printing adhesion issues
If you want to print with PETG then the PE sheet is not really a good choice. Better to use the powder-coated textured sheet.
https://help.prusa3d.com/article/flexible-steel-sheets-guidepost_2195
Hope this helps!
RE: Clear PETG printing adhesion issues
I've printed petg on that sheet yes the textured sheet is better but as long as you use glue stick on that bed u will be good also I'd say it's damp fillament try drying it
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