PID Tuning With Filament Flowing (heater feedforward M309)

[gallaghersart]

Was wondering if there was a way to also have a constant flow of filament while PID tuning was taking place?

Just was thinking that the filament would be cooling the hot end during the test and this might help Speed/Max flow 3D prints.

Thanks!
`mike

*** FYI, By Posting this and other Ideas on this website, my personal websites and others I hereby say this is open source and forgo any patent rights so all can use. Acknowledgment would be nice, but not required.

[dc42]

@gallaghersart see the M309 command, https://docs.duet3d.com/en/User_manual/Reference/Gcodes#m309-set-or-report-heater-feedforward. This command is new in RRF 3.4.

[Del87]

@dc42 some manuals how to calibrate S value? I have best results with M309 S0.03 (lowest temperature fluctuation by extruding the same amount of filament (PETG 235 degrees) on same speed G1 E60 F200).