Pressure advance issues
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SCRATCH THAT, I was implementing it in the config.g, works in the starting gcode just fine
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I found that I needed to increase the acceleration and jerk values when I started to use pressure advance, otherwise the printing speed was reduced.
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I found that I needed to increase the acceleration and jerk values when I started to use pressure advance, otherwise the printing speed was reduced.
The extruder jerk 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 jerk 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 jerk values when I started to use pressure advance, otherwise the printing speed was reduced.
The extruder jerk 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 jerk 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 jerk 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 jerk 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 jerk 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-Jerk 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 jerk 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 jerk 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