PETG or Polyethylene Terephthalate Glycol is a very tough material with good thermal resistance. PETG has a low thermal expansion, so even when printing big objects without an enclosure, it practically does not warp. It’s almost as easy to print as PLA, but it can offer many mechanical properties that PLA prints just can't. It is less brittle, ductile and cannot burn. It also offers a healthy amount of flexibility which can prevent parts from breaking under stress.
Unlike PLA or ABS, PETG tends to ooze a bit and may leave strings of plastic on your print. You can fight this with increasing retraction and playing with hotend temperature, but if you use our filament presets in PrusaSlicer, we already did that for you and the amount of stringing is minimal. If you still witness a tiny bit of stringing, you can get rid of it by quickly blasting your finished prints with a heat gun.
PETG sticks very well to PEI, which is generally a good thing. However, sometimes it could stick a little bit too well, and you could rip a piece of PEI coating from the bed. To prevent that from happening, apply a separating agent (e.g., glue stick) onto the print surface.
Recommended bed temperature: 85°C for the first layer, 90°C for the other layers
Easy to print
Possibility of stringing
Good layer adhesion
Not soluble in acetone
Very tough and durable
Bonds strongly to the print surface
High temperature resistance
Water and humidity resistant