what hapens with successive sub-step relative extrusions?



  • Are sub step size quantities of extrusion simply ignored (when using relative extrusion) or does the firmwhere have a running total of these and it will for example output a step of extrusion for every ten tenths of step?


  • administrators

    It keeps a running total of the fraction of a microstep that is outstanding, until it reaches a whole microstep. But this wasn't working properly until firmware version 2.02/1.23.



  • Thanks.

    What is the minimum resolution that it would handle well?

    Not asking on the back of a fault, I just got the parser to kick out a warning message for sub-microstep sized extrusions and it almost looked like the program was stuck in a loop dumping out hundreds of warnings for moves from a standard height Benchy build.



  • Just cleaned up the parser a bit and the number of short vectors is a small percentage of the total numbers of moves. Extrapolating further still it is likely that the total length of these vectors will be an even smaller fraction of the total distance travelled by the nozzle.

    Catching the fault was a good effort! I'm guessing it came from the multicolour work rather than observed build issues on single material extrusion?

    Edit:

    Total moves: 109178

    Vectors shorter than one microstep (16 microsteps)
    Small x vectors: 13
    Small y vectors: 0
    Small z vectors: 0
    Small e vectors: 700

    Vectors shorter than one physical stepper step
    Small x vectors: 248
    Small y vectors: 0
    Small z vectors: 0
    Small e vectors: 69174

    Vectors shorter than one physical stepper step (if I swapped for 0.9 steppers)
    Small x vectors: 115
    Small y vectors: 0
    Small z vectors: 0
    Small e vectors: 19956


 

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