Hi all, novice user here so hopefully someone can help. I have an issue where the beginning of nearly every extrusion is delayed so the print head is moving for a second or so before any filament comes out leaving a gap. Here’s a pic to see what I mean:
You can see the small gaps in the upper right inner wall where it started and the outer surface at the bottom left corner of the window where it started again after doing a move. This also happens at the start of the skirt but the rest completes OK. It doesn’t seem to be a bed adhesion problem as there is no spare filament floating around the print bed and what is extruded seems to be sticking very well.
I have tried different retract settings as well as switching it off altogether and have tried different filaments including the one that cane with the snapmaker originally. I have even opened up the print head to ensure the path the filament takes has no obstructions etc.
Does anyone have any suggestions of what else I could try? I have a spare hot end would it be worth trying that?
Thanks in advance,
Brendhan
Have you calibrated linear advance? That tends to help with underextrusion at the beginning of print moves.
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The entire print is suffering from underextrusion. Have you calibrated your E-steps?
Teaching Tech 3D Printer Calibration
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Just calibrated my E-steps @CNC-Maker it now seems much better ‘filled out’, thanks for the tip and the link. However it didn’t help with the original issue and it is still under-extruding after a move.
@bobby4718 I tried to run through the linear advance calibration from the link that @CNC-Maker gave me but the test pattern rather failed to print:
Also when I issued the M900 command the printer did not return anything at all not even an OK, not sure if that means it’s set to 0 or linear advance isn’t enabled in the firmware, I assume Snapmaker have enabled it?
Thanks both for your suggestions, I’ll keep trying to get the test pattern to work. Any further suggestions would be much appreciated.
If M900 is not returning anything, are you trying to do this over a WiFi connection? If so, you need to be doing this over a USB connection. WiFi connections have issues when issuing commands, as you are actually talking to the TouchPad and not the Controller.
Ah yes, makes sense when I try over USB I get the expected “echo:Advance K=0.04” response. I’ll have another go at the test pattern tomorrow, getting a bit late here now. Cheers.
Think I’ve got it now, increasing the test print thickness to 0.28mm seemed to improve the legibility/adhesion. A combination of both the E-steps and the linear advance along with a few tweaks to the filament profile seems to have mostly sorted the issue. It’s not perfect as it is still slightly under extruding for the first couple of mm but with the better extrusion rate the remaining tiny gaps are filling in nicely. Here is what I did for anyone interested:
- E-Steps calibration: was extruding 93.5mm when it should have been 100mm - corrected.
- Linear Advance: went from K0.04 to K0.02 - doesn’t sound like much but seemed to make a noticeable difference.
- Reduced the nozzle temp to 205° (after I had put it up to 215° doing a bit of experimenting)
- Returned the first layer extrusion to 100% from 120% (was done to try and fix the under-extrusion before I calibrated the E steps)
Both done with the help of the link from @CNC-Maker . As I said not perfect but enough to be getting on with for now and get my home brewery controller finished!
Thanks again guys and here is the final print (and initial + working prints…):
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