Volumetric flow limits with PLA and PETG – a Voron experience

I built a Voron 2.4 to try to print faster than my faithful Prusa farm units could manage, but when trying to set expectations I found frustratingly few hard numbers in terms of what kind of volumetric flow people were achieving with a similar setup. In some ways that’s not surprising since a lot of people with Vorons etc. print ABS instead of PLA.

Here are the numbers I am seeing so far, using a Voron 2.4r2 with Rapido hotend, Stealthburner and LGX Lite extruder.

I’m going to try some different speeds after seeing other people hitting 25mm³/s with PLA – something is obviously missing from the equation here! Stay tuned.

Volumetric Flow Limit of PLA

0.4mm nozzle, generic, PLA @ 215deg – 15mm³/s, 16mm³/s resulted in inconsistent extrusion

0.4mm nozzle, generic, PLA @ 230deg – 16mm³/s. 17mm is just starting to show inconsistent extrusion and it’s more clear by 18mm³/s.

0.6mm Bondtech CHT nozzle, PLA @ 215deg – 18mm³/s. 20 results in inconsistent extrusion.

Volumetric Flow Limit of PETG

  • 0.4mm generic nozzle – 12mm³/s is OK with chamber doors closed @ 240 filament and 65% cooling. Also 250 @ 50% fan.
  • 0.6mm Bondtech CHT nozzle – 14mm³/s is OK @255deg and 100%. fan. 15mm³/s causes inconsistent extrusion at 240 filament/65% cooling. 265deg and 100% fan results in 15mm³/s flowing OK but heat soak killed the print 2 hours in. Will re-test after improving the chamber exhaust fan.

General Notes

Aurarum PETG doesn’t extrude at 230 – I find I need to have the hotend at at least 240. 93pc seems to be the sweet spot for the flow rate.