Low temperature filaments, Nozzle temp under 100C

Hello,

I'm working on test prints with some very interesting " PCL Low Temperature Filament - Black - 2.85mm" material and wanting to know if there is an easy way to allow for extrusion when the nozzle is under 125C with either a Taz Pro dual .5 or a Taz 6 SE/.5mm nozzle.  

I’ve created a material profile and have the slicing settings prepped for my tests but it doesn’t seem to want to enable extrusion motor until I reach that 125C with the nozzle.

  • Based on pre-print tests with manual extrusion ~95 - 110C seems optimal and at 125C it is very problematic and can tend to bound in the extruder drive even without retraction.

Suggested print settings:

  • 70°C - 140°C printing range
  • Heated print bed not required. If needed, use bed at 45°C
  • Print slow, speed:10~40mm/s

Thank you and I appreciate any help or suggestions!

There might be some firmware limiters that are in place. I don’t know for sure as its a bit of a rabbit hole.

There are indeed firmware limitations:

#define PREVENT_COLD_EXTRUSION
#define EXTRUDE_MINTEMP 120

You will have to build custom firmware to change these limits.

There is a g-code to allow cold extrusion but I don’t remember if it is enabled in the Lulzbot firmware. It is “M302 S0” to disable temperature checking. You could try going into the console in Cura, enter that, and see if it will allow you to extrude at lower temperatures, or add that to the start code in Cura and re-slice your file.

Thank you all for your helpful hints and tricks!

I have edited a Marlin firmware and I’m planning on upgrading and testing that sometime this week. But I also like the “cold Extrude” g-code override. I’m curious to see how it does maintaining the nozzle temp through the duration of the print.

I’ll report on the results. Fun stuff!!!