Nozzle crashes during print start or stops too high

dc42

To find your Z probe trigger height (G31 Z parameter), see https://duet3d.dozuki.com/Wiki/Test_and_calibrate_the_Z_probe.

Hint: if your printer digs into the bed when starting the print, your G31 Z parameter is too high.

bellus

@phaedrux said in Nozzle crashes during print start or stops too high:

As a way to eliminate the probe hardware from the equation entirely and to test the Z axis positioning specifically, you can switch over to use M558 P0probe type. That will use manual jogging whenever G30 is called. So you'll have to use the display to drop the nozzle down until it just touches the bed.

https://duet3d.dozuki.com/Wiki/GCode#Section_M558_Set_Z_probe_type

So I tried this first, manually jogging this during homing works as advertised. BUT, when starting a print, X & Y home and then the pop up for Z comes up but it’s un-responsive. Clicking of the Z movements does nothing.

bellus

@dc42 said in Nozzle crashes during print start or stops too high:

To find your Z probe trigger height (G31 Z parameter), see https://duet3d.dozuki.com/Wiki/Test_and_calibrate_the_Z_probe.

Hint: if your printer digs into the bed when starting the print, your G31 Z parameter is too high.

I think I understand the Z offset better now. I followed the calibration. I repeatdably got 2.053 about 6 times. But it still drives into the bed, granted not as bad though.

dc42

Does this problem only occur when you start a print file, or does it also occur if you try to home the printer manually?

If it only occurs when you try to print a file, please post the first 50 or so non-comment lines of the print file.

You have your max Z speed set to 600mm/min in M203, which is quite high seeing that your Z steps/mm is 1600 in M92. You may be losing Z steps because of trying to move the Z axis too fast.

bellus

@dc42 said in Nozzle crashes during print start or stops too high:

Does this problem only occur when you start a print file, or does it also occur if you try to home the printer manually?

If it only occurs when you try to print a file, please post the first 50 or so non-comment lines of the print file.

You have your max Z speed set to 600mm/min in M203, which is quite high seeing that your Z steps/mm is 1600 in M92. You may be losing Z steps because of trying to move the Z axis too fast.

Correct, only while starting a print. All axises home correctly, then Z lifts approximately 10mm or so. when the print begins Z descend right into the bed. Every time I have initiated homing and even during mesh bed compensation it works flawlessly.

*M107
M190 S75 ; set bed temperature and wait for it to be reached
M104 S215 ; set temperature
G28 ; home all axes
G1 Z5 F5000 ; lift nozzle
; Filament gcode

M109 S215 ; set temperature and wait for it to be reached
G21 ; set units to millimeters
G90 ; use absolute coordinates
M82 ; use absolute distances for extrusion
G92 E0
G1 E-2.00000 F120.00000
G92 E0
G1 Z0.400 F4800.000
G1 X92.212 Y89.205 F4800.000
G1 E2.00000 F120.00000
G1 F1800
G1 X92.637 Y88.772 E2.03205
G1 X93.334 Y88.124 E2.08232
G1 X94.213 Y87.375 E2.14338
G1 X94.781 Y86.937 E2.18124
G1 X95.550 Y86.380 E2.23146
G1 X96.106 Y86.019 E2.26650
G1 X96.726 Y85.657 E2.30444
G1 X97.515 Y85.234 E2.35171
G1 X98.203 Y84.918 E2.39175
G1 X98.683 Y84.737 E2.41883
G1 X99.722 Y84.395 E2.47665
G1 X100.566 Y84.160 E2.52297
G1 X101.231 Y83.990 E2.55923
G1 X102.131 Y83.819 E2.60765
G1 X103.208 Y83.738 E2.66472
G1 X115.192 Y83.690 E3.29807
G1 X115.923 Y83.724 E3.33670
G1 X117.305 Y83.876 E3.41018
G1 X118.207 Y84.029 E3.45857
G1 X118.740 Y84.140 E3.48733
G1 X119.694 Y84.389 E3.53943
G1 X120.474 Y84.642 E3.58274
G1 X121.308 Y84.964 E3.63003
G1 X121.874 Y85.211 E3.66264
G1 X122.669 Y85.599 E3.70938
G1 X123.829 Y86.239 E3.77942
G1 X124.366 Y86.575 E3.81288
G1 X125.088 Y87.072 E3.85922
G1 X125.606 Y87.463 E3.89348
G1 X126.270 Y88.014 E3.93909
G1 X127.206 Y88.867 E4.00600
G1 X128.109 Y89.792 E4.07437
G1 X128.509 Y90.248 E4.10639
G1 X129.330 Y91.292 E4.17656

I did go ahead and change M203 to 100mm to see if that made a difference and did not.

Phaedrux

Can you post your homeall file?

bellus

@phaedrux

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v2 on Tue Feb 05 2019 20:31:22 GMT-0700 (MST)
G91 ; relative positioning
G1 Z5 F2400 S2 ; lift Z relative to current position
M98 Pdeployprobe.g ; deploy mechanical Z probe
G1 S1 X-245 Y-225 F1800 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 X5 Y5 F2400 ; go back a few mm
G1 S1 X-245 Y-225 F360 ; move slowly to X and Y axis endstops once more (second pass)
G90 ; absolute positioning
G1 X15 Y15 F2400 ; go to first bed probe point and home Z
G30 ; home Z by probing the bed

; Uncomment the following lines to lift Z after probing
;G91 ; relative positioning
;G1 S2 Z5 F40 ; lift Z relative to current position
;G90 ; absolute positioning

M98 Pretractprobe.g ; retract mechanical Z probe

Phaedrux

@bellus said in Nozzle crashes during print start or stops too high:

M98 Pdeployprobe.g ; deploy mechanical Z probe
M98 Pretractprobe.g ; retract mechanical Z probe

Remove those from your homeall. The G30 command will deploy and retract as needed. This could be causing your issue.

bellus

![alt text](image url)@phaedrux said in Nozzle crashes during print start or stops too high:

@bellus said in Nozzle crashes during print start or stops too high:

M98 Pdeployprobe.g ; deploy mechanical Z probe
M98 Pretractprobe.g ; retract mechanical Z probe

Remove those from your homeall. The G30 command will deploy and retract as needed. This could be causing your issue.

Removed as suggested, no change. The only thing that seems to help is to Z offset. Running the calibration of the probe I would religiously get right around 2mm. I changed it to .75mm and it wasn’t as bad.

bellus

Here’s a quick video https://youtu.be/Jux1Wyts-B0

bellus

@bellus

At 0 even it’s not crashing and actually attempting to print. Nozzles about .5mm to high.

Phaedrux

@bellus said in Nozzle crashes during print start or stops too high:

Here’s a quick video https://youtu.be/Jux1Wyts-B0

So what command was running in that video? It probed once and then dropped the nozzle into the bed. Was that G28? G29? G30? G32?

bellus

@phaedrux

It’s the G28 command, when it starts a print, probes once, then nose dives. I was actually able to get past that point by changing the Z offset to 0, but like I said it’s a bit high(roughly 1mm). I re-measured the Bl touch base from the nozzle tip, it’s almost exactly 8mms.

Phaedrux

Can you post the contents of your config-override.g file?

bellus

@phaedrux

As requested,

; This is a system-generated file - do not edit
; Heater model parameters
M307 H0 A66.5 C483.4 D6.2 S1.00 V12.1 B0
M307 H1 A680.2 C325.1 D11.5 S1.00 V12.0 B0
M307 H2 A633.9 C320.4 D13.3 S1.00 V12.0 B0
M307 H4 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H5 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H6 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H7 A340.0 C140.0 D5.5 S1.00 V0.0 B0

I also was to able to set the trigger height to 0.500 with positive results. It’s printing, albeit a blobby mess, just needs a bit of tuning. Honestly don’t know why the trigger height is so low compared the calibration steps, but it’s working.

; Drives
M569 P0 S1 ; Drive 0 goes forwards
M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S1 ; Drive 2 goes forwards
M569 P3 S1 ; Drive 3 goes forwards
M569 P4 S1 ; Drive 4 goes forwards
M350 X16 Y16 Z16 E16:16 I0 ; Configure microstepping without interpolation
M92 X79.86. Y79.86 Z400.0 E390.12:390.12. ; Set steps per mm
M566 X2000.00 Y2000.00 Z50.00 E120.00:120.00 ; Set maximum instantaneous speed changes (mm/min)
M203 X6000.00 Y6000.00 Z100.00 E200.00:200.00 ; Set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z60.00 E100.00:100.00 ; Set accelerations (mm/s^2)
M906 X1100.00 Y1100.00 Z1600.00 E1000.00:1000.00 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

; Axis Limits
M208 X-130 Y-110 Z0 S1 ; Set axis minima
M208 X130 Y110 Z300 S0 ; Set axis maxima

; Endstops
M574 X1 Y1 S1 ; Set active high endstops

; Z-Probe
M574 Z1 S2 ; Set endstops controlled by probe
M307 H3 A-1 C-1 D-1 ; Disable heater on PWM channel for BLTouch
M558 P9 H5 F120 T2400 ; Set Z probe type to bltouch and the dive height + speeds
G31 P25 X0 Y0 Z0.5000 ; Set Z probe trigger value, offset and trigger height
M557 X15:220 Y15:210 S15 ; Define mesh grid

; Heaters
M305 P0 T100000 B4138 R4700 ; Set thermistor + ADC parameters for heater 0
M143 H0 S110 ; Set temperature limit for heater 0 to 110C
M305 P1 T100000 B4138 R4700 ; Set thermistor + ADC parameters for heater 1
M143 H1 S250 ; Set temperature limit for heater 1 to 250C
M305 P2 T100000 B4138 R4700 ; Set thermistor + ADC parameters for heater 2
M143 H2 S250 ; Set temperature limit for heater 2 to 250C

; Fans
M106 P0 S1 I0 F500 H1 T180 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned on
M106 P1 S1 I0 F500 H2 T180 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on

; Tools
M563 P0 S"Right" D0 H1 ; 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
M563 P1 S"Left" D1 H2 ; Define tool 1
G10 P1 X16 Y0 Z0 ; Set tool 1 axis offsets
G10 P1 R0 S0 ; Set initial tool 1 active and standby temperatures to 0C

; Automatic power saving
M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000" ; Set voltage thresholds and actions to run on power loss

; Custom settings are not configured

; Miscellaneous
M501 ; Load saved parameters from non-volatile memory
T0 ; Select first tool