PETG on the Ender 3

I did some more internet searching and found some more wisdom on printing PETG on the Ender 3. Nobody said anything about issues with the stock Ender 3 print bed so I decided to give it a try. I printed with the following:

  • The filament I used is MatterHackers Build Series PETG in Black.
  • Temperatures - nozzle at 240C, bed at 55C to start and then 20C thereafter. Mine only cooled down to 30C after 30+ minutes of printing.
  • Fan - off for first 2 layers then 100% thereafter.
  • Speed - normal print speed of 30 mm/sec. Yes, it's slow but it works. The recommendation I found said that 40 mm/sec would probably be OK though.
  • NO SPECIAL BED PREPARATION. As long as it's level it works.
I've only printed one part so far this way but I have to say that it worked great and I had no difficulties getting it off of the bed. I think it might have been easier than PLA because it just popped off. I'm a real believer now and will probably start using PETG more.

The only gotcha of course is switching between PLA and PETG. When switching to PETG you should make sure you force all of your old PLA out before you print. When going back you of course have to heat to the PETG temperature (240C) and get the PETG flushed out. Contrasting colors make this much easier to do (I went from orange to black on my first switch). If you try to do this with the same color you won't be able to tell when one is flushed out.

PETG is 'gooey' and will create long and very fine strings when you pull the filament out. When you are feeding it in it will tend to ooze out of the nozzle. To minimize this do a little manual 'retraction' by turning your extruder wheel back a couple of millimeters.

Last but not least remember that your PETG is HYGROSCOPIC and MUST be kept in a sealed container.