Filament not stopping at the nozzle
Hi all,
I have bought the I3Mk3S and the MMU2s kits. I initially assembled and tested the printer without the mmu on it and it was all ok (printed a really nice batman)
After assembling the MMU I had a few rookie bugs I worked out (pfe tubes too tight etc) but have now hit a major snag. The filament loads to the MMU fine and then pushes out to the nozzle great but it then keeps coming forming a great donut shape around the nozzle. I have kept this going for 30 seconds incase it is doing some sort of cleaning but it does not seem to want to stop.
My feeling is it the filament sensor on the printer not detecting that the filament is there yet and continuing to pump it through until it "finds" it.
To clarify I have attempted the following;
Checked the filament sensor cable connected in the box and it is correctly mounted
Checked the cable for breaks/shorts and it is good
Replaced the IR sensor board with the one that came in the MMU2s Kit (I know there the same) incase it was faulty
Nothing shows up on the self test
If anyone can help it will be greatly appreciated
Thanks
RE: Filament not stopping at the nozzle
Got it. I found an article which explains the exact operation of the filament sensor and the tension screw was wrong.
RE: Filament not stopping at the nozzle
Hi Herbiedc3. I am having the same issue where the filament keeps coming out into a pile. What was the solution? Do you have a link to the article? Thanks
RE: Filament not stopping at the nozzle
Hi Michael,
The link that opened it up for me was as below
https://help.prusa3d.com/article/wprwemqsmj-ir-filament-sensor-calibration
The issue I had was with the tensioning of the rocker which is linked to the bondtech gears within the extruder. I fixed it using a method used for another printer, I will list what I did.
Do all of this cold
1. Remove the PFTE tube from the extruder
2. loosen all the way the idler screw on the left hand side of the extruder (40mm screw with the spring)
3. Cut a piece of filament approx. 20cm long (not critical but longer is better than shorter)
4. Push the filament into the extruder all the way to the hotend (you will have a lot out that is good)
5. tighten the idler screw until you can move the filament but with strong resistance
6. Remove the filament you should hear a click as the bondtech gear springs back
7. Replace the PFTE tube
This fixed my issues and it is printing without any problems now
I hope this helps
RE: Filament not stopping at the nozzle
Thank you for the link and the steps Herbie. 😀 I will try it out tonight