Bizarre DAA Extrusion Issues



  • I had been chasing down some ringing artifacts on my custom tool changer and after playing with acceleration and jerk settings to no avail, I gave Dynamic Acceleration Adjustment a try. Printing a single test cube I found that M953 F38 reduced my artifacts tremendously.

    The obvious next step was a multi material print. After a few layers I paused the print and noticed my extrusions were all messed up. The solid infill looked way under extruded, and it seemed like the perimeters on the first few layers were over extruded.

    I played around with extrusion multipliers, extrusion temperatures, extrusion widths, extruder acceleration and jerk settings, all the normal stuff...

    I was lost until a community member mentioned DAA, and I immediately commented out DAA and did my test prints again.

    It looked perfect, but more investigation was needed.

    I did many tests, and have shown 4 of them below. Each print consisted of 2 40mm squares only 0.80mm tall printed on separate extruders and about 5mm apart. The pictures are only of 1 of the 2 squares printed in each test, the others are red and don't show the artifacts as easily. Print speeds were around 25mm/s with 1 perimeter and 10% infill overlap.

    The changes between them are self explanatory on the sheet.

    image0.jpg

    It seems to me like DAA is affecting the behavior of my extruder, but I am not sure. Prints without DAA are clearly better, in terms of this issue, than those with it turned on.

    Any ideas or suggestions would be greatly appreciated.

    (Hemera direct drive tools set up without any weird settings)
    (Running a Duet 3 FW 3.1.1 and Tool Boards with FW 3.1.1)


  • Moderator

    Please post your config.g so we can see your speed, etc settings



  • The relevant part:

    M84 S120 					    					  ; Set idle timeout
    M203 X18000 Y18000 Z800 C5000 E5000:5000:5000:5000	  ; Set maximum speeds (mm/min); Maximum speeds (mm/min)
    M201 X2000 Y2000 Z180 C500 E6000:6000:6000:6000	  	  ; Absolute Max Accelerations (mm/s^2)
    M204 P1500 T2000									  ; Max Print and Travel Accelerations
    M205 X6 Y6 Z3 E12:12:12:12 C1.5						  ; Maximum jerk speeds mm/sec
    M593 F38 L180										  ; DAA


  • @KevinMar said in Bizarre DAA Extrusion Issues:

    The relevant part:

    M84 S120 					    					  ; Set idle timeout
    M203 X18000 Y18000 Z800 C5000 E5000:5000:5000:5000	  ; Set maximum speeds (mm/min); Maximum speeds (mm/min)
    M201 X2000 Y2000 Z180 C500 E6000:6000:6000:6000	  	  ; Absolute Max Accelerations (mm/s^2)
    M204 P1500 T2000									  ; Max Print and Travel Accelerations
    M205 X6 Y6 Z3 E12:12:12:12 C1.5						  ; Maximum jerk speeds mm/sec
    M593 F38 L180										  ; DAA
    

    Keep in mind M205 is in mm/min NOT mm/min
    Try:
    M205 X360 Y360 Z180 E720:720:720:720 C90 ; Maximum jerk speeds mm/sec

    Your current values are crazy low... I think

    M205 vs M566, oops!



  • nope, M205 is in mm/sec (see https://duet3d.dozuki.com/Wiki/Gcode#Section_M205_Set_max_instantaneous_speed_change_in_mm_sec: This command is provided as an alternative to M566 for compatibility with Marlin. In M566 the units are mm/min as with all other speeds. In M205 they are in mm/sec.)



  • @oliof said in Bizarre DAA Extrusion Issues:

    nope, M205 is in mm/sec (see https://duet3d.dozuki.com/Wiki/Gcode#Section_M205_Set_max_instantaneous_speed_change_in_mm_sec: _This command is provided as an alternative to M566 for compatibility with Marlin. In M566 the units are mm/min as with all other speeds. In M205 they are in mm/sec.)

    Oh man, totally correct! I hadn't started drinking my coffee yet when I wrote my comment! 😪 Thanks for catching that!


  • Moderator

    @KevinMar I wonder if you have your max accelerations set too low. DAA should be allowed to choose the acceleration based on the frequency you've targeted.

    https://duet3d.dozuki.com/Wiki/Gcode#Section_M593_Configure_Dynamic_Acceleration_Adjustment

    Acceleration limits set by M201 and M204 will still be honoured when DAA is enabled, so DAA will only ever reduce acceleration. Therefore your M201 and M204 limits must be high enough so that DAA can reduce the acceleration to the optimum value.



  • I raised my xy accelerations to 6000 and my E accelerations to 12000 i believe. Still getting funky results.


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