Extruder motor stops during print…

ofloveandhate

OP here. d300vs with firmware RepRapFirmware for Duet Ethernet version 1.19.2 (2017-09-01), Duet Ethernet 1.0.

repeated failures of the following kind:

the extruder stops responding to moves, with no error message. only way to get it responsive is to M999 or power cycle.

d300vs thread here: http://forum.ultibots.com/viewtopic.php?f=59&t=297

dc42

I suggest you start by upgrading the firmware to 1.20. It provides better monitoring of the stepper drivers, so it may warn you if the driver is reporting an unusual status.

If the issue recurs, after it has happened and before rebooting, please send M122 to get a diagnostic report. Also send M906 without any parameters and confirm that the current is still set correctly.

ofloveandhate

ok, thanks. will report back in a few days.

ofloveandhate

another failure

M906
Motor current (mA) - X:1000, Y:1000, Z:1000, E:400:400:400:400:400:400:400:400:400, idle factor 30%

M122
=== Diagnostics ===
Used output buffers: 3 of 32 (9 max)
=== Platform ===
RepRapFirmware for Duet Ethernet version 1.20 running on Duet Ethernet 1.0
Board ID: 08DDM-9FAMU-JW4S4-6JKD8-3SD6L-TMXMS
Static ram used: 11992
Dynamic ram used: 98816
Recycled dynamic ram: 3880
Stack ram used: 1216 current, 8448 maximum
Never used ram: 7936
Last reset 27:23:06 ago, cause: power up
Last software reset at 2018-01-26 12:31, reason: User, spinning module GCodes, available RAM 10464 bytes (slot 0)
Software reset code 0x0003 HFSR 0x00000000, CFSR 0x00000000, ICSR 0x0441f000, BFAR 0xe000ed38, SP 0xffffffff
Error status: 0
Free file entries: 10
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest block write time: 0.0ms
MCU temperature: min 41.0, current 41.2, max 60.2
Supply voltage: min 23.8, current 24.4, max 24.9, under voltage events: 0, over voltage events: 0
Driver 0: standstill, SG min/max 0/1023
Driver 1: standstill, SG min/max 0/1023
Driver 2: standstill, SG min/max 0/1023
Driver 3: standstill, SG min/max 0/1023
Driver 4: standstill, SG min/max not available
Date/time: 2018-01-27 15:56:14
Cache data hit count 4294967295
Slowest main loop (seconds): 0.607014; fastest: 0.000045
=== Move ===
MaxReps: 5856, StepErrors: 0, FreeDm: 240, MinFreeDm 120, MaxWait: 2357420531ms, Underruns: 0, 1
Scheduled moves: 0, completed moves: 0
Bed compensation in use: none
Bed probe heights: 0.000 0.000 0.000 0.000 0.000
=== Heat ===
Bed heaters = 0 -1 -1 -1, chamberHeaters = -1 -1
Heater 0 is on, I-accum = 0.0
Heater 1 is on, I-accum = 0.5
=== GCodes ===
Segments left: 0
Stack records: 2 allocated, 0 in use
Movement lock held by null
http is idle in state(s) 0
telnet is idle in state(s) 0
file is idle in state(s) 0
serial is idle in state(s) 0
aux is idle in state(s) 0
daemon is idle in state(s) 0
queue is idle in state(s) 0
autopause is idle in state(s) 0
Code queue is empty.
=== Network ===
State: 5
HTTP sessions: 1 of 8
Responder states: HTTP(1) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)

what should i try next? i have not yet tried the other extruder pins on my board. i also have a wifi i can try, but that's pretty invasive, and it makes connecting a PITA.

ofloveandhate

ok, so i tried something. with the machine in its errored state, i swapped the extruder motor pins to E1, instead of E0. then, i made a new tool in the web interface.

switching to the new tool on the other pins allowed me to extrude! then, as a sanity check, i swapped the pins back to E0, changed back to the original tool, and was unable to extrude. ok, i am not insane. switch to new tool on E1, extruding is ok.

i think i will try printing on E1.

ofloveandhate

i printed on E1 last night, to no avail. still failed. i am unable to connect to the printer, "due to the duet firmware". wish i had a screencap of the page – did a refresh, and now get nothing. i am unable to connect to the printer through any other means. my normal fallback of repetier host, simplify3d, and all other programs fail to connect.

i have now wasted about two kg of plastic due to this problem...

ofloveandhate

so, i swapped boards to my wifi board, with firmware 1.19.2. another failure.

i updated on the wifi to 1.20, and am reprinting now.

ofloveandhate

another failure, on my wifi, 1.20. we can safely say:

either neither of my duet boards are defective, or both are
if this is a firmware problem, it exists in 1.19.2 and 1.20

i additionally believe that

we can rule out my wiring as a problem. otherwise, when i switched E0 to E1, the extruder would not have moved without a restart. however, if my wiring is causing this fault, it should be firmware detectable… ideally

one problem i have observed is that the firmware is unable to detect if the extruder motor comes disconnected. you can unplug, and replug, no errors. should this not be observable?

ofloveandhate

is this the same problem as i am experiencing?

https://community.ultimaker.com/topic/4733-print-stops-or-fails-halfway-through/

ofloveandhate

it seemed so at first, but no, my fans work fine. that post was about heat creep, not the motor stopping.

dc42

Does extrusion stop at the same point in the print each time?

The stepper drivers on the Duet can in theory detect when a motor wire is disconnected, but in practice we found it gave false positives, so I disabled that facility. If I can find a way to filter out the false positives, I will enable it again.

ofloveandhate

another thought i had – maybe i should put a fan on the duet? is the board overheating?

https://www.duet3d.com/wiki/Connecting_and_configuring_fans

ofloveandhate

no, it is not the same point every time.

ofloveandhate

here's a snippet of what my gcode looks like:

G1 X-9.773 Y20.202 E0.0240
G1 X-8.049 Y19.083 E0.0845
G1 X-7.228 Y18.592 E0.0393
G1 X-5.829 Y17.806 E0.0660
G1 X-2.005 Y15.805 E0.1774
G1 X-1.749 Y15.664 E0.0120
G1 X-0.741 Y15.031 E0.0489
G1 X-0.182 Y14.575 E0.0297
G1 X0.225 Y14.087 E0.0261
G1 X0.746 Y12.742 E0.0593
G1 X0.847 Y12.526 E0.0098
G1 X0.864 Y12.365 E0.0066
G1 X0.745 Y10.941 E0.0588
G1 X0.342 Y9.133 E0.0761
G1 X-0.212 Y7.194 E0.0829
G1 X-1.216 Y3.878 E0.1424
G1 X-1.686 Y2.198 E0.0717
G1 X-1.997 Y1.061 E0.0484
G1 X-2.338 Y-0.306 E0.0579
G1 X-2.657 Y-1.687 E0.0582
G1 X-3.138 Y-4.143 E0.1029
G1 X-3.300 Y-5.092 E0.0396
G1 X-3.519 Y-6.570 E0.0614
G1 X-3.767 Y-8.725 E0.0892
G1 X-3.921 Y-10.510 E0.0736
G1 X-4.038 Y-12.900 E0.0984
G1 X-4.060 Y-14.016 E0.0459
G1 X-4.047 Y-16.295 E0.0937
G1 X-3.986 Y-17.935 E0.0674
G1 X-3.894 Y-19.398 E0.0602
G1 X-3.771 Y-20.858 E0.0602

so it is a sequence of short extrusion moves the whole file. no long linear extrudes, just this.

ofloveandhate

here are my four attempts at 'seepferdchen'

ofloveandhate

another thought: should i prefer absolute or relative extrusions? i have only been using relative through this whole process.

ofloveandhate

i am starting to think there is a bug in the reprap firmware, in the part that processes relative extrusion distances. i printed the same model, same supports and all settings, last night. only change was that in simplify3d, i switched to absolute extrusion.

ok, there was another difference that i should have not let happen, and that was that i printed this one without the https://www.thingiverse.com/thing:2567240 bottom corner plates.

i am re-printing the same file now. if it fails again, then we know that the relative / absolute distances had nothing to do with my problem. if it succeeds, we have stronger evidence that it is a firmware bug.

ofloveandhate

i am now convinced that there is a bug in the firmware dealing with relative extruder distances

another success with absolute extruder distances, print time was 36h 21m

video:
https://youtu.be/7BCaq2k_oJk

pic:

a little problem at the top. caused due to top layers being set to 0 for that process in simplify3d. (6 processes used total, to reduce the amount of plastic used by varying the infill %)

dc42

Most Duet users - including me - only ever use relative extrusion distances.

Did you turn off "Allow zeroing of extrusion distance" in S3D? You should do that when using relative extrusion, although AFAIK it doesn't matter if you leave it enabled.

ofloveandhate

zeroing was indeed allowed in s3d, both in my relative and absolute prints.

brad at ultibots indicated that he thinks people mostly use absolute, where you think it is relative…

i have > 70 hours of absolute distance printing with no errors now, so am growing in confidence that i was experiencing something problematic with relative. i think some stress-test kinds of gcode files are merited. i was thinking that cylindrical circles or ellipses with ever-smaller faces might be useful, and mix in the zeroing.

are there known smallest distances that the extruder should be asked to perform? i read the code in the reprap firmware, and nothing immediately jumped out at me as risking underflow or rounding error. i was however concerned in GCodes.cpp at lines 2044 or so,

const float moveArg = eMovement[0] * distanceScale;
float requestedExtrusionAmount;
if (gb.MachineState().drivesRelative)
{
  requestedExtrusionAmount = moveArg;
}
else
{
  requestedExtrusionAmount = moveArg - virtualExtruderPosition;
  virtualExtruderPosition = moveArg;
}

that in one case, the value of virtualExtruderPosition is adjusted, and not in the other. is it assumed to be always 0 if relative? where is it adjusted?

i just want to know exactly how to manifest this problem, as i am not content with absolute distances as a workaround.