Filament stuck on 4th Extruder
Hello all,
I can print multicolored on extruder 1 to 3 without any blockages no matter how many tool changes are done. But when I add the 4th extruder the filament will get stuck eventually in the steel tube of the Y-Splitter after ~200 layers of printing (I can print flat objects with 4 colors without the filament getting stuck). Then I have to unscrew the QSM-M5 fitting of the multiplexer, cut the filament above the steel stube and push it out the other way.
The fact that it only happens on the 4th extruder and only after a while lets me believe that it is not a printer/slicer setting but some hardware issue, like not perfectly aligned steel tube or the steel tube being just a bit too narrow or the spring tension is not right. I tried to fiddle around with all that but without success. Does anyone have any other suggestions I might try?
Thanks 😉
RE: Filament stuck on 4th Extruder
Try running a print in single mode and use extruder 4 and see if it fails on that.
this can be done in Slic3r or Prusa Control
You can run test on the drive and observe it better with just one drive running
and then if you get it running smooth then move on to the MMU prints.
also I would print basic models like the "Benchy" for test.
share your results and i'll see if I can help further.
RE: Filament stuck on 4th Extruder
I find every so often a filament path acts up and wants something done to them.
I have a Prusa,therefore I research.
RE: Filament stuck on 4th Extruder
Ya I find that the cheaper filaments dont do so well in the MMU or just printers in general,
I have had good luck with fillamentum., Colorfabb, and Prusa filaments.
RE: Filament stuck on 4th Extruder
As I said I don't have any issues with the first three extruders, the blockage only occurres on the 4th. Printing single with only extruder 4 works of course because there is no tool change involved. My filament of choice I use with success (except on 4th) is FormFutura, prints very clean and reliable.
RE: Filament stuck on 4th Extruder
Well then then the only thing I can suggest is doing a process of elimination and see what area might be causing the issue.
You can also look at the PTFE tube on the hotend, I had a issue once with feeding after I changed it out and the inner bevel on the tube was not enough and it would jam on random extruders.
Also I remember my #3 extruder having similar issue when I first assembled my MMU.
First I would check the spring tension on the extruder gears,
I do this when the filament is loading and hold my fingers on the filament while it loading and put some pressure on it to see if I can get it to slip in the drive.
If it doesn't slip then I unload the filament then check to see if the gears are gripping tighter than the other or is pealing filament loose,
If so then its probably to tight.
Second I would try switching the location of the tubes on the Multiplexer on top of the print head,
Say #1 and # 4 locations
Leave the metal connectors and metal tubes in there current locations.
If the issue changes to say #1 is jamming and #4 is now running correctly then the issue is in the Multiplexer on the top of the extuder.
If not then you have a issue most likely with the drive section,
Such as spring tension, Motor connector, Motor could be bad, Set screw on drive gears has come loose, etc.
Simple way to test the motor would be to make a MMU print for drive #3 and #4 and then switch the cable connection on the board,
If it still fails on #4 then its probably a issue just with that drive but if #3 fails then there may be a issue with the board or motor.
I hope this helps,
also if you have some pictures of the Multiplexer or the drive tension springs, etc. maybe it will help us see something you dont.