I observed that my M200 developed strange issue - extruder loses steps nearly continously during raft printing.
It sometimes clicks every now and then during part printout but I didn't notice significant degradation in quality (I'm printing only in Z-ABS).
First layer of raft seems underextruded because of that.
I tried leveling the bed, autocalibration comes out fine, I cleaned extruder gear, replaced nozzle with new one, I even replaced entire hotend - no success, clogged nozzle is not the problem here.
Problem is worsening over time - Extruder started skipping some steps when printer had ~700h of total print time, now it has ~1000h and it skips every second step.
Some part is obviously degrading and needs replacement but I don't have a clue which one to replace and I don't want to take blind guesses. Have You faced this issue before?
Stepper motors should not lose torque over time, gear teeth look and feel sharp as new, Cables should be fine too - if it was the cable is should lose steps everywhere not on raft only (it skips when high extrusion rate is used)
Take a straightedge and make sure table is flat (high spots can block nozzle exit on first couple passes). You might want to remove table pcb and clean out as pcb holes/underneath can become loaded extrusion. Make sure the filament feed block to the hot end is clear (not just hot end). Some people have had to replace the extruder bearing, check it's running smooth..while doing that make sure extruder gear isn't too far back on shaft (hitting motor or set screw hole in path of filament) Also possible thermal couple not working right, too cold.
I jinxed it... Tonight print failed and I woke up to smell of burned plastic.
Now extruder skips steps even when trying to load the material but this is probably due to burned plastic inside nozzle.
I disassembled entire extruder to clean everything - bearing and screw holding it seem fine (screw is not damaged, bearing runs smoothly).
Extruder gear got covered in plastic chips but this happened tonight because of this failure - path of the filament is correct, it does not hit the set screw or anything.
I took a closer look at recently printed parts and they seem just a little bit underextruded compared to earlier prints. I'm placing my bet on heater or thermocouple.
I just ordered replacement, we will see if that was causing the issue.
By case I mean thermocouple housing - metal can connected to screen and then to white wire with blue dots - it was shorted to black wire.
I will get replacement heater after weekend (Every store is out of stock, WTF?), and I need this printer working ASAP (I have deadline and I need some plastic parts).
I sawed open thermocouple housing and black wire was exposed and touching metal.
Extruder was not skipping steps without material.
Heater has 15.5 Ohms, picture in your post does not load.
I'm still not sure what was the real problem - I reassembled thermocouple after wrapping it with kapton tape (It should last few days until new one arrives),
cleaned everything and reassembled heating block and extruder - printer now works perfectly fine, thanks for your time.
One last thing - inside thermocouple housing one of the wires looked like it was connected to external metal can intentionally (just left there bare) -
I'm still not sure what was the real problem - I reassembled thermocouple after wrapping it with kapton tape (It should last few days until new one arrives),
cleaned everything and reassembled heating block and extruder - printer now works perfectly fine, thanks for your time.
One last thing - inside thermocouple housing one of the wires looked like it was connected to external metal can intentionally (just left there bare) -
can You confirm if this is the case?
It's possible that the set of heater&thermocouple wasn't installed correctly in the hotend causing problems with getting a demanded temperature and, in consequence, melting the material sufficiently.
Also, you mentioned that the extruder gear was covered with plastic chips and there was burned plastic in the nozzle.
So we have 3 potential reasons of the failure. I'm glad the problem is gone.
Not sure which wire you're referring to. Please contact me via PM.
Alright. I experience this same issue, however only with external filaments. But, this issue sounds the exact same.
The printer seems to be over-extruding and thinks that it cannot push as much filament as it wants to, and the clicking is a slight retraction of the filament to overcome this.
A simple fix is to turn down the flow ratio under raft settings until the clicking is resolved. However, since your issue is worsening, it sounds like you’re having a nozzle clog. Get a new nozzle.
Nope, nozzle was fine, same thing happened with new one.
My problem was faulty heater - I replaced it and problem went away for ~1000h of printing time and then it came back, I replaced heater again and it prints OK, hopefully for next 1000 hours or so.
It seems that heater can fail in some strange way that it still produces enough heat to melt the plastic, but not enough to keep it flowing. From outside it looks like nozzle clog, but it is not. Eventually nozzle WILL become clogged and prints will fail with hotend covered in burned plastic.
This is pure speculation, but I think that resistive wire in heater breaks off after hundreds of hours in high temperature and many heating/cooling cycles but it still makes contact - heater still looks like it’s working (It gets hot) but either it has higher resistance now (produces less power) or delivers heat intermittently leading to clogs.
BTW. this thread is a little bit stale (11 months old)
(11 months old)