Starts printing fine, then stops feeding (but thinks it is still printing)

[perlguy 0]

Several times now my Ultimaker has stopped feeding during a long print, but the printer keeps going like it thinks it is still printing.

I had first thought that the extruder motor was getting too hot, but even with a fan blowing on it (and keeping it cool) I am still having this problem.

Probably 80% of the time, things print just fine. But the other 20% are driving me crazy.

Any tips/suggestions about what I can do to troubleshoot and solve this problem?

Thanks!

 

[gr5 963]

1) Is it possible that it isn't that the motor is turning but the filament was kind of shredded and isn't feeding anymore?

Assuming you are correct:

2) The extruder won't extrude if the temp of the head goes below 170C. Were you printing at a low temp (like 185C or colder)? Sometimes the temp fluctuates a bit over the course of a minute.

3) If not the above 2 issues then probably a loose wire to the stepper. I would hook up prontrface and remove filament and extrude continuously and slowly and jiggle all the wires especially at the ends where they connect to the stepper and on the PCB underneath.

4) If the wires still seem fine and it's not head temp then most likely next issue is the stepper driver chip. These little chips can be removed (they are socketed). I believe you can put any rep rap pololu in the same spot but I'm not certain. Maybe you need to keep these cool better. Or you could try swapping the extruder one with another one such as Z axis. Or you could try reducing the current by the tiniest amount by turning that little pot on it.

http://wiki.ultimaker.com/Electronics_build_guide#Tuning_the_stepper_motor_drivers

edit: Oh and those steppers are amazingly tough. I doubt it is possible for it to suddenly stop working completely just because it is hotter than usual. These things can take quite a bit of heat and abuse. They are extremely simple inside - just coils of wires that move the shaft due to magnetism.

 

 

[illuminarti 16]

What speed, temp, layerheight are you printing? When you say it stops feeding - do you mean the motor stops turning, or just that filament stops coming out of the nozzle?

This is on a UM1, right?

 

[doguri 0]

I've noticed the same problem on our UM1.

Same issue, on long prints, the extruder stops feeding.

- The feeder motor does not turn.

- If you pause the print and release steppers it moves freely. (didn't check if you could resume the print, however you can restart the print from there and its fine.

Also for the model I was printing, it seemed to occur within the first 10 layers.

My setup:

-UM1 (with dual extruder kit)

-Connected USB to Windows 7 64bit

-Cura 14.1 (Out of the box setup / Only tweaked fill and layer height)

Coincidentally I noticed this behavior sometime after installing the 2nd extruder kit and upgrading Cura to 14.1.

Also, when this happens the print continues to its end and does not cooldown the extruder.

(I was able to hand crank the extruder to clear out what got left inside.)

Normally reprinting again seems to be fine.

Thanks.

 

[perlguy 0]

Printing with PLA at 210C on a UM1.

Print speed was only at 60mm/s last night when this happened. 0.1mm layer height. Although it happens when I am at 0.2mm hight as well.

The filament isn't grinding, the motor simply stops.

Also, when this happens and the print "finishes", my heated bed is properly switched off - but the nozzle does not, so it stays at 210C until I manually shut it off.

During a "normal" print, when everything works correctly, both the extruder and the heated bed are turned off when the print finishes.

 

[doguri 0]

This does seem like the same issue. I was printing at 0.2mm layer height.

I did notice in Cura's printing window, "Term" tab, a message said something about extruder feeder protection enabled due to low temperature. (even though the temp was at 220C) Also on the Cura print graph I see spikes in the temperature for the extruder, but doesn't seem to be affecting anything.

I was thinking that when it does happen, something sees the "wrong" temperature drop and shuts off the extruder.

I'll try to get the exact message when it happens again.

 

[gr5 963]

You two seem to have different problems. Even though the temp is set to 210 or so, doguri's printer seems to think the head is getting below 170C which is where Marlin stops letting you extrude. This is 90% of the time caused by a bad wire at the top of the print head that connects from the little board then up through the cable harness to the PCB under the UM1. Usually the individual subwires inside the insulation (close to the connector) bend back and forth too many times and break. Unfortunately UM solders these wires which is bad - they are supposed to be crimped. When you solder, solder spreads into/under the insulation on some of the wires and makes them stiff and repeated bending can lead to an intermittent open. Sometimes an easy way to prove this is to heat up the head with steppers off and immediately start pushing the print head around to the 4 corners and you will see the temperature fluctuate to 0C or something similar.

A super easy fix is to use the second extruder temp cable. At least do this as a test to verify the fix. But then of course you can't use a second extruder. So I guess the best solution is to run a new wire for the first extruder and then make damn sure you provide good strain relief with that black delrin plastic E shaped part so this doesn't happen again.

so it stays at 210C until I manually shut it off

It sounds like perlguy has a different problem. Does the display show 210/210? or something like 150/210? If the former then the problem is more likely a with the wiring to the stepper or with the pololu. Reread steps 3 and 4 in my previous post and follow those debugging instructions and report back.

 

[perlguy 0]

When it screws up, the display shows 210/210.

 

[gr5 963]

So did you diagnose using my suggestions #3 and #4 above?

 

[doguri 0]

Update for my issue... The wires tested okay. It appears that printing from SD card works fine.

Unfortunately I used an older version of Cura to get the gcode on the SD card. So its either something going wrong when printing directly with Cura or the newer version of Cura.

 

[gr5 963]

extruder feeder protection enabled due to low temperature.

 

This is an intermittent error that only occurrs if you push the head around in certain positions because of a loose wire. So sometimes you will see it and other times you can print just fine. The version of cura or using SD card has nothing to do with this. Until you fix the wiring this error will come back to haunt you.