How to tune Acceleration and Jerk on large pellet printer
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I'm a bit lost as where to start. I've got a large-format 3d printer that uses a screw pellet extruder. I'm trying to implement pressure advance, but what I'm noticing is that when I'm satisfied with values of pressure advance, it substantially slows down my print time. I can speed the print back up by increasing the jerk values in X and Y, but that causes my extruder to skip steps. So my question is, where do I start since acceleration and jerk in X,Y, & E all affect each other (with pressure advance enabled).?
The values I only know for sure are max accelerations for X and Y, and RPM of the extruder.
Thanks
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@p8blr The usual culprit which fits your description of events is extruder jerk being too low. Given that in any G1 move the axes travel and extruder travel have to be synchronised, then it's fair to say that if extruder jerk is too low, it will affect the X and Y axes as well. Conversely, if extruder jerk is high then in order to keep X, Y and E synchronised, it will effectively be overridden by the axes jerk values. Therefore, it is safe to set extruder jerk to a "silly high" number where it cannot interfere with any G1 Xn Yn En move. The only time extruder jerk could potentially come into affect (other than when it is set low and pressure advance is being used) is for extruder only moves which don't involve a reversal of direction (I can't think of any such moves).
