Extruding Problem

Snapmaker 2.0
1

Hello its been a while since i was active here. I mainly used the SM for CNC and Laser bc I allways had problems with the print quality.
Yesterday i needed to print something big on the SM otherwise i had to split the model!

Now the Problem is that on some spots the printer is underextruding but the esteps are calibrated. On the other side the print stringed a lot the print temp. was not the problem i print allways with the same filament and i set the retract to 0,6mm with 60mm/s

Are there some new ways or things to calibrate?
Im happy with every help

I will also share the Cura project files.

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2

Wow, that looks strange… Stringing is just a matter of tweaking the retraction settings - I’m always advertising to add a bit of extra prime amount to avoid underextrusion after travel, but your problems look like something else…
I’m lost here. Perhaps backlash? Check your linear modules for play - if you mill a lot, you may have loose parts or worn nuts? See here: https://support.snapmaker.com/hc/en-us/articles/1500000110341-What-should-I-do-when-the-slider-of-the-Linear-Module-comes-loose-
Perhaps this helps: Print Quality Guide

1 Like
3

Hey there thanks for the tipps i will look trough the links.
What are your retract settings and extra prime settings so i can see if its get better

4

Currently running a print with these settings in Cura, and it looks good so far:

grafik

Things I changed from default:

  • minimum travel: I do not want retraction too often - I accept a bit of stringing, since retration sometimes makes things worse in other aspects. So I changed to 5 mm, sometimes even more.
  • extra prime amount: To compensate for oozing during travel. Went higher earlier, but that then caused overextrusion at the start of print after travel. N.b.: Cura uses volume (mm³) - most other slicers use length (mm). In Prusa Slicer I use 0.2 mm.
  • Maximum count: The small extruder gear of SM2 with its sharp teeth quickly gnaws through the filament - the default of 90 is flirting with desaster!
  • Z-Hop: Never yet used it, but people say it reduces likelihood of knocking over large prints. May be worth switching on.
1 Like
5

Ok you are using the default retraction and this is good? I tought for a direct drive extruder it is too much but i will test it thanks. The extra prime could be a success

6

Never bothered to change retraction distance - 5 mm is a lot, I guess 2 would be enough.

1 Like
7

I will test it hope it dont make it worse because when the retract is more it takes more time to extrude right?

8

As I understand it, retraction goes like this: print - retract X mm - travel - push in again by X mm plus extra prime amount - continue to print. So, in an ideal world, the retraction distance should not really matter. Aside from that retract/push in by X mm takes longer the larger X is. But we talk about fractions of a second. Of course in a long print, it adds up, so you’re right in that sense.

1 Like
9

Sounds logical the part iv printed took 38h to print so in this case it would add some time

10

Could it be old filament? You said it’s been a while since you used the SM for a print?

11

Hey there! No thats not the issue i used the same roll for other parts on another printer and went totally fine

12

So with 5mm retract and the extra prime amount it looked a lot better! I will also slow down the print speed a little bit and it should also gibe a improvement. But lot of stringing was going on