Rotating Magnetic Sensor - Keeps Pausing Printer

[T3P3Tony]

@wouldstain I don't think there is much more infor available from the logging. What would be good is cutting down the print (you can run it above the bed rather than as an actual print) to just a layer to two that triggers the 0/-'ve results.

[dc42]

@wouldstain do you still get the problem if you print with PLA using exactly the same settings as as you did for the successful PETG print, apart from temperatures? In particular, using the same pressure advance and retraction settings, if your hot end can handle that when using PLA.

[wouldstain]

@dc42 @T3P3Tony
I've tried printing the same model, only swapping out the filament between prints and re-running the same job. I've tried adjusting only the temp. I've tried changing and not changing retraction settings. I've tried adjusting and not adjusting z-offset when switching.

I've also tried printing PLA with the PA set to zero with 2/25 retraction.

I've had no problems printing small TPU jobs (I'd be happy to print something larger to let it run if you think it would be helpful)

I have not printed ABS recently but I can if you think it would be worth testing.

I'm using am E3Dv6 / Bondtech BMG extruder so it's a pretty standard set up.
I've also replaced the short and long bowden tubes, throat and nozzle as well as pulling apart the extruder and cleaning it.

I'm inclined to think that this is not an issue with the MFM and that the MFM is just a symptom. I have not seen a repeat of the issue with PETG yet on things like the drywall anchor. Previously, I had only been able to print one at a time. I've tested as many as 6. Sadly, I don't need that many drywall anchors at the moment but It's good to know I have them if i need them!

I had mentioned this previously and @T3P3Tony suggested a new thread. I will open one shortly.

[wouldstain]

@t3p3tony

As soon as the print pauses, I can either resume or drop the bed and have it do an extrude with no issues. I'm able to successfully resume printing for the most part in either case until it happens again.

[PetrKroupa]

Today I upgraded to BETA6 and it is interesting that my sensor started pause job. On BETA5, no problems.

M591 D0
Duet3D rotating magnet filament monitor v3 on pin 121.io1.in, disabled, sensitivity 24.80mm/rev, allow 75% to 125%, check printing moves every 5.0mm, version 3, mag 131 agc 91, measured sensitivity 25.72mm/rev, min -56% max 107% over 10658.5mm

My setup is 6HC+1LC, SBC. bondtech mosquito.

I must disable sensor because it is not possible to print.

; Configuration file for Duet 3 (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.2.3 on Wed Apr 21 2021 11:35:55 GMT+0200 (Středoevropský letní čas)
M81 C"pson"
G4 S1
M80


; General preferences
G90                                                      ; send absolute coordinates...
M83                                                      ; ...but relative extruder moves
M550 P"velkej"                                           ; set printer name
G4 S1


; Drives
M584 X0.0 Y0.1 Z0.2:0.3:0.4:0.5 E121.0										; set drive mapping
;M569 P40.0 S0 R1 T3:3:50:50
;M569 P41.0 S0 R1 T3:3:50:50
;M569 P40.0 S0 R1 T2.7:2.7:6:6										; change enable polarity, active = disable drive
;M569 P41.0 S0 R1 T2.7:2.7:6:6									; change enable polarity, active = disable drive
M569 P0.0 S1
M569 P0.1 S0	
M569 P0.2 S0										; physical drive 0.2 goes forwards
M569 P0.3 S0
M569 P0.4 S0                                            ; physical drive 0.3 goes forwards
M569 P0.5 S0


M671 X26:380:380:26 Y20:20:380:380 S10


M350 X16 Y16 Z8 E16 I1      		                            ; configure microstepping with interpolation
M92 X142.22 Y142.22 Z400.00 E420.00                      ; set steps per mm
M566 X600.00 Y600.00 Z60.00 E150.00                      ; set maximum instantaneous speed changes (mm/min)
M203 X18000.00 Y18000.00 Z1500.00 E7500.00               ; set maximum speeds (mm/min)
M201 X5000.00 Y5000.00 Z250.00 E5000.00                   ; set accelerations (mm/s^2)
M906 X1200 Y2500 Z2000 E450 I40         		                   ; set motor currents (mA) and motor idle factor in per cent
;M569 P40 T2.7:2.7:2.7:2.7
;M569 P41 T2.7:2.7:2.7:2.7
M84 S10                                                  ; Set idle timeout

; Axis Limits
M208 X-5 Y0 Z0 S1                                         ; set axis minima
M208 X400 Y400 Z420 S0                                   ; set axis maxima

; Endstops
M574 X1 S1 P"io2.in"                                     ; configure active-high endstop for low end on X via pin io0.in
M574 Y2 S1 P"io5.in"                                     ; configure active-high endstop for low end on Y via pin io1.in
M574 Z1 S2                                               ; configure Z-probe endstop for low end on Z

; Z-Probe
M950 S0 C"121.io0.out"                                       ; create servo pin 0 for BLTouch
M558 P9 C"^121.io0.in" H5 F400 T18000                         ; set Z probe type to bltouch and the dive height + speeds
G31 P500 X26 Y0 Z1                                     ; set Z probe trigger value, offset and trigger height
M557 X30:400 Y5:400 S41                                 ; define mesh grid

; Filament sensor
M591 D0 P3 C"121.io1.in" S1 R75:125 L24.8 E5.0

; Heaters
M308 S0 P"temp0" Y"thermistor" T100000 B3950             ; configure sensor 0 as thermistor on pin temp0
M950 H0 C"out0"  Q10 T0                                       ; create bed heater output on out0 and map it to sensor 0
M307 H0 B0 R0.161 C1877.2 D21.70 S1.00                                  ; disable bang-bang mode, set PWM limit
M140 H0                                                  ; map heated bed to heater 0
M143 H0 S120                                             ; set temperature limit for heater 0 to 120C
M308 S1 P"121.temp0" Y"thermistor" T500000 B4723 C1.19622e-7 ; configure sensor 1 as thermistor on pin temp1
M950 H1 C"121.out0" T1                                       ; create nozzle heater output on out1 and map it to sensor 1
M307 H1 R2.856 C161.2:95.6 D7.68 S1.00 V24.9                                         ; disable bang-bang mode for heater  and set PWM limit
M143 H1 S300                                             ; set temperature limit for heater 1 to 300C

;CPU temperature calib
M912 P0 S-12

; Fans
M950 F0 C"121.out1" Q500                                     ; create fan 0 on pin out7 and set its frequency
M106 P0 S0 H-1                                           ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"121.out2+out2.tach"  ; Q500
;M950 F1 C"121.out2+121.out2.tach"															; create fan 1 on pin out4 and set its frequency + snimaní otáček
M106 P1 S1 H1 T50                                        ; set fan 1 value. Thermostatic control is turned on

; Tools
M563 P0 S"Mosquito" D0 H1 F0                             ; define tool 0
G10 P0 X0 Y0 Z0                                          ; set tool 0 axis offsets
G10 P0 R0 S0                                             ; set initial tool 0 active and standby temperatures to 0C
; M591 													  ;filament sensor monitor

M150 X1 Q3000000
M150 U120 S15
; Custom settings are not defined

M955 P121.0 I42  ; specify orientation of accelerometer on SAMMYC21 with CAN address 121

; Miscellaneous
T0                                                       ; select first tool

Presure advance is used: M572 D0 S0.04

[T3P3Tony]

@petrkroupa please share the gcode file you were printing that has this issue. Also what Z height did you have the really bad low value.

[PetrKroupa]

@t3p3tony - Here is file - 0.6 nozzle, PLA https://uloz.to/tamhle/FnGywCyC0Lbx#!ZGNmZQR2AwZ1ZmV0BGV3LzExATWvBUuvGQOzJUqHASq3MwSvBD==
It is 8Mb. I had to upload it to another server. Anyway, the error occurred many times in the first 4 layers. Then I turned off the sensor (m591 D0 S0). Today morning before the end of printing I tried M591 D0 and measured sensitivity was min -53% max 105%. Printing was completed successfully without any problems.

Z height? Do you mean : G31 P500 X26 Y0 Z1? Or?

[T3P3Tony]

@petrkroupa thanks. The answer to the Z height question is that it happened many times in the first few layers. Just makes it easier to reproduce if I don't need to print the whole part.

[PetrKroupa]

@t3p3tony - maxi_dvojka_CUT- Telo32-2_0.6n_0.3mm_PLA_velkej_2h10m.gcode

OK, here is a cut off model. It is only 1.5 mm high. Sliced with same setings.

I thing my Z height is OK. Not too much on the bed. BuildTak doesn't like it. Rather, I feel like I'm almost too high. However, the value entered in G31 still depends on the position of the probe. I use BLTouch and I believe it's ok. Anyway, I believe this is not a filament sensor problem.

first layer:

[alankilian]

@petrkroupa I notice your layer change has something I've never seen before:

• Two very fast negative movement on the extruder.
• Normal speed negative movement on the extruder
• Normal speed positive movement on the extruder

This is the only unusual thing I see.

Starting at line 730 in the file:

;WIPE_START
G1 F14400
G1 X264.546 Y233.289 E-.42543
G1 X264.445 Y232.993 E-.04957
;WIPE_END
G1 E-.025 F2400
G1 Z.7 F18000
G1 X265.067 Y236.944
G1 Z.2
G1 E.5 F2400
;TYPE:External perimeter

[PetrKroupa]

@alankilian - Hmm Im using prusa slicer. the question is what is there for. Most likely it's a remnant of the original profile. But the error always occurs somewhere during the layer, I never observed it at the beginning. But good point, thanks. I try remove it.

[alankilian]

@petrkroupa If you can slice something smaller, I can try printing on my Delta and see if I get errors also. (If you can center at (0,0) that would be even better.)

[dc42]

@petrkroupa likewise, if you can slice it centred at (0,0) I will try it on my delta and on my toolchanger.

[PetrKroupa]

@alankilian, @dc42 - Today i will finish last big print. Then I will try to create some small GCODE (50 * 100mm) where the error will definitely show up. I'll test it and upload it here. We'll see what shows. So far, it seems that the error does not occur during the first layer.

[PetrKroupa]

@dc42 - One question, if the problem was somewhere on the HW side, the measured % value would be lower. Because the sensor simply turns less than the extruder. Correct?

However, this does not explain how a min -53% can happen. The extruder would have to create the filament.

Am I thinking right or am I completely out of it?

[PetrKroupa]

I finally figured out what was happening.

sensor.mp4

When the filament is slightly bent, the sensor restarts. Not always. But I managed to film it during manual extrusion. What is certain is that it cannot be wiring because nothing moves. It's weird that it only showed up with BETA6, but until then I didn't have a problem with it.

The question is why the sensor restarts.

[alankilian]

@petrkroupa said in Rotating Magnetic Sensor - Keeps Pausing Printer:

When the filament is slightly bent, the sensor restarts

OH! That's a good catch.

[dc42]

@petrkroupa is the AGC value reported by M591 consistently below 100 ?

[PetrKroupa]

@dc42 - Yes, it is solid somewhere between 91-93. I also verified that the spindle rotates freely and has no axial move.

I tried to tap the sensor in various ways, bend the connectors and twist it in every way. Strange....

[dc42]

@petrkroupa I think either there is a dodgy power connection somewhere, most likely in the wiring but possibly on the PCB itself; or something is causing the watchdog timer to time out. I can't see any reason in the firmware why the watchdog timer would time out, other than bad power or a transient causing the microcontroller to get into a bad state.

If you are sure that you can't provoke it or temporarily fix it by bending the wiring, then I suggest we replace the circuit board. Please email warranty@duet3d.com with a link to this thread.