Pressure advance issues
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I found that I needed to increase the acceleration and [censored] values when I started to use pressure advance, otherwise the printing speed was reduced.
The extruder [censored] value is the critical one. The extruder acceleration during printing moves is limited to the lower of the value you specified in M201, and the [censored] converted to mm/sec and divided by the amount of pressure advance.
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I found that I needed to increase the acceleration and [censored] values when I started to use pressure advance, otherwise the printing speed was reduced.
The extruder [censored] value is the critical one. The extruder acceleration during printing moves is limited to the lower of the value you specified in M201, and the [censored] converted to mm/sec and divided by the amount of pressure advance.
M201 X1000 Y1000 Z15 E1000 ; Accelerations (mm/s^2)
M203 X15000 Y15000 Z300 E3600 ; Maximum speeds (mm/min)
M566 X600 Y600 Z30 E200 ; Maximum [censored] speeds mm/minuteOkay, so… If M201 is E1000 and M566 is E200 (mm/m) I'd be limited at the 1000mm/s on acceleration?
If i take 200 / 60 and divide that by .1(pressure advance) I get 33.3mm/s
Am i doing that right? Should I adjust any of that? o.O;
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That's all correct. You don't need very high extruder acceleration for printing moves (and pressure advance doesn't affect the acceleration for retract and un-retract moves); however 200mm/min extruder [censored] is unusually low, so the associated acceleration limit for printing moves that it causes might have an effect.
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That's all correct. You don't need very high extruder acceleration for printing moves (and pressure advance doesn't affect the acceleration for retract and un-retract moves); however 200mm/min extruder [censored] is unusually low, so the associated acceleration limit for printing moves that it causes might have an effect.
Okay! Glad to hear! I believe I even upped that from where it was before… wondering if this might be the cause of my issues haha
What E-[censored] settings would you recommend? Using a e3d Titan with pancake stepper..
Thanks,
-Casey -
I'm experimenting with some pressure issues here too. Stumbled on this thread, with adding M572 D0 S0.2 (I have an unusually long bowden tube) things seem much better- still tinkering. What are we actually changing with pressure advance?
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I've just added wiki page https://duet3d.com/wiki/Pressure_advance#How_to_enable_and_configure_pressure_advance.
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Thanks DC42. Perfect explanation.
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That's all correct. You don't need very high extruder acceleration for printing moves (and pressure advance doesn't affect the acceleration for retract and un-retract moves); however 200mm/min extruder [censored] is unusually low, so the associated acceleration limit for printing moves that it causes might have an effect.
Sorry to dig up an old thread but I am just now configuring my own pressure advance. What would you recommend for extruder [censored] with a 3:1 gear bowden extruder and a ~60cm long bowden tube?
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I am also tuning the Pressure Advance. I have found a a K-factor calibration guide for Marlin at http://marlinfw.org/docs/features/lin_advance.html and a G-Code pattern generator in http://marlinfw.org/tools/lin_advance/k-factor.html.
Will this approach work for Duet?.
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Well replacing the instructuon fir Marlin
[[language]] M900 K0.x ; set K-factor ```by
[[language]]
M572 D0 S0.x