UM3E Stalls during initial filament purge

[CTotten 18]

Twice in the last few days, I have started a print on my UM3E, only to have the machine basically stall during the initial filament purge (the glob it puts down in the front/left corner).  In both cases, I had to shut the machine off to get it to stop.  Normally, it purges for a few seconds, then lowers the print bed a bit while purging for a few more seconds, then moves to begin the actual print.  The total time is normally no more than 10 seconds.  The first time, it purged for about 30 seconds (at the initial height, and never lowered the bed) before I realized what was happening.  It made quite a mess on the nozzle.  After that was cleaned up, I started the print again and it worked fine.  Today, I went to run another batch off the same G-Code file, and it did this again.  I caught it quicker this time, so less of mess.  As with the previous time, I started the print again and it worked fine. 

 

Any ideas?  I have had this machine for 12 months, and have never seen this before.  The firmware has not been updated recently, and the same Cura version has been in use for months.

Edited October 24, 2018 by CTotten

[Smithy 1,144]

I had this issue too some time ago and later a second time. I think it has something to do if you abort a print. At least in my case I aborted a print before and after starting the print again I had this issue. In my opinion it is independent if you say "retry this print" or start from scratch. So if I have to abort a print, I do now always a restart of the printer just to be sure. 

 

Someone else reported that he had similar issues when not confirming that the object was removed after a print and the printer was turned off before pushing the button.

 

And the issues are not always the same. I had it onetime like you, the material was pushed out without moving the head up, resulting in a mess and another time I had the issue without extruding any material at all. But in all cases, after a reboot and printing the same gcode again, it was working fine.

 

 

[CTotten 18]

I think in both cases it was following an aborted print.  Interesting.  I will add that to my workflow to make sure the printer is power cycled after an aborted print.  Hopefully that will prevent that from happening again.

[Smithy 1,144]

For me it never happened again when I do a restart. 

But yes interesting that you also had it after an aborted print.

[Smithy 1,144]

I forgot today to power cycle the printer after I had to abort a print job. I aborted the job and said no I don't want to retry the print. Then I sent I new file from Cura and the printer went in a "hanging" state while doing the prime blob, resulting in a very very big blob which was not stopping extruding until I switched the printer off before something flood my print head. Also aborting, pause is not working in this state.

 

So this is definitely a bug in the UM3 (haven't tried it yet for the S5). Seems that not all will be cleaned up after aborting.

[Brulti 177]

I've had to abort several prints in the past couple weeks for various, but I did not observe this behavior in my UM3E at all. I did not power it off after aborting, sometimes I would just says 'Yes' when it asks me if I want to retry, sometimes not and start something else or the same print after tweaking something I had forgotten. So it's not a general bug.

 

Still mysterious though. Maybe the log file could help find out what the problem is? I've no diea how to read it, but we have several people on this forum who can and who might find out what the problem is.

[CTotten 18]

It could be related to the firmware version.  I have not updated my firmware in 9 months or so.  I will try to post the firmware version currently on my machine later this week. 

[Brulti 177]

There was definitely a firmware update at some point in the past nine months, that might be it.

[Smithy 1,144]

I am on the latest firmware, so I don't think it is fixed in the latest one. I am not sure if it is every time I abort a print, but when it happens it was definitely after an aborted print.

[Brulti 177]

Unless your firmware update bugged, it seems unlikely to be firmware-related as the latest update isn't recent and such a problem would have had these forums flooded by reports if it was the firmware.

 

One way to know would be to reset the printer to factory settings, do a test print to see if the problem persists or not, then update the firmware again and run another print and see what happens.

[Smithy 1,144]

I will try to get the log after it happens again. Normally I don't have to abort prints often, just when printing with PETG, this f*cky material will not always stick very well to the bed, so I have to retry it sometimes when the print comes off.

[Patronus 3]

I've had the same problem a few times in the last few days. My UM3 goes into a frenzy and keeps purging with no end in sight. The only way to stop it is to switch off the machine. In my case it also happened after an aborted print.

[Smithy 1,144]

There is definitely a bug but happens not always. After my last aborted print nothing happened, started normal, so I was not able to catch the log.