I've had an Anet A8 for a few years now and always printed in PLA, however I recently saw that PETG is much stronger and more flexible than PLA which for me often cracks as it's very brittle.
I bought a roll of PETG, put it into the printer, cranked up the extruder temperature to 220 and tried printing. Unfortunately the Marlin thermal runaway protection keeps kicking in and stopping my print mid way through. On the first few prints the base would be printed perfectly, but the within the first few layers the extruder temperature kept dropping and the printer shut off, I found that this was due to the cooling fan running too much and cooling the extruder end. I then turned the fan down to 10% and printed again, this time the print started off really well, but after around 100 or so layers the printer stopped due to the extruder cooling down. I don't know whether the temperature slowly kept dropping as I wasnt watching the printer at the time.
Does anyone have any experience with PETG on an Anet A8 and can offer any advice? I guess the following may help but all have side effects
- Printing with 0%, 2%, 5% cooling fan speed, but may cause issues with the print
- Printing slower to stop the extruder end cooling too quick, but would significantly increase print times
- Maybe a hardware upgrade? Maybe replacing the heating element with a better one, but then the board may not be able to cope with the extra current and might be a bit of a fire risk.
Any thoughts would be much appreciated, I'm almost thinking I will either have to stick with PLA or get a new printer that's more capable of maintaining the extruder temperature.
The prints mentioned above were at 0.2mm layer height but can't really do any lower as the items are quite large and take 16 hrs to print already.