Nozzle dragging



  • I'm using Cura 3.0 and everytime my nozzle is performing a travel move, it will drag the perimeters or the infill. So the bad way is when I got layer shift. I have Z hop enabled in cura and if I print two parts with space between them I get a z lift. But not when the head is printing the same part. What should i tweak? And also, it seems like everytime I have a head travel move, the first thing is the travel move is performed and then I get retraction. I thought first time i should get a retraction and then a travel move not reverse.
    In this picture https://ibb.co/d0u2aR the blue line indicates a travel move. On that travel move I want to have a Z lift but I don't have it.



  • That's controlled by the combing setting. By default it enables combing everywhere. The alternative settings are no combing on skin regions or no combing at all. Myself, I nearly always set the combing mode to "no skin" except when printing super runny stuff like PETG when I disable combing completely. Hope this helps.



  • You rock. Problem solved. Thanks alot!



  • Beside the fact that now everytime a retraction is made, the Z hop is performed, there are still some travel moves over the printed part when retraction is not active. So, the Z hop is not performed. And I have some cases when during this travel moves, the print head is hitting an infill or perimeter and I'll get skipped steps. Is there a way to have the Z hop at travel move even when I don't get retraction?



  • Hi, I'm not totally sure what the problem is there, can you post a link to a sample gcode so I can check it out?



  • If the nozzle is hitting previously printed infill or perimeters, that would indicate to me that those parts have been over extruded.



  • https://we.tl/IhYJToyFiE

    here it is. What I did after this i have lowered the travel speed to 150mm/s and the print speed to 60mm/s. I can still hear the nozzle hitting but because it's at lower speed, it won't skip steps.



  • That gcode was created with combing mode = all so it will move over any of the existing lines with no z-hop and no retraction. If you want to reduce the amount the nozzle smashes into the existing lines, set the combing mode to "no skin" or turn it off completely (as mentioned above). Cheers.



  • @burtoogle:

    That gcode was created with combing mode = all so it will move over any of the existing lines with no z-hop and no retraction. If you want to reduce the amount the nozzle smashes into the existing lines, set the combing mode to "no skin" or turn it off completely (as mentioned above). Cheers.

    Yep, it's getting better and better. I also have a problem with over-extrusion at the edge of perimeters on solid infill. I don t have a picture but i think I have to tweak my jerk. Now it's 15mm/s. When I print the solid infill at 120mm/s speed, the print head is making a small pause when touching the inside perimeter (inside edge of the object). In that time, extruder still have some inertia and will extrude more than it's needed. I'm thinking increasing jerk will make the print head to not pause that long when touching perimeters.



  • I wish you good luck, I wouldn't dream of trying to print anything at 120mm/s but, then again, my priority is quality rather than speed.


 

Looks like your connection to Duet3D was lost, please wait while we try to reconnect.