Crash into bed on Z home

okamitok

For the life of me cannot solve an issue with my new IR sensor.
Below are my setting, following these instructions, https://miscsolutions.wordpress.com/mini-height-sensor-board/

Sending G92 Z0 and then G30 S-1 works fine and it homes.

[[language]]
M558 P1 X0 Y0 Z1 H5 F120 T6000
G31 P500 X0 Y2.4 Z0.949 ; Set Z probe trigger value, offset and trigger height

But when I then run the homez it always crashes into the bed.
Here is my homez file:

[[language]]
; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool on Sat Oct 21 2017 21:17:08 GMT-0500 (Central Daylight Time)

; Lift Z relatively to current position
G91
G1 Z5 F6000

; Back to absolute positioning
G90

; Go to first bed probe point and home the Z axis
G1 X30 Y27.6 F6000
G30

; Uncomment the following lines to lift Z after probing
;G91
;G1 Z5 F100
;G90

dc42

If you send these commands manually:

G1 X30 Y27.6 F6000
G30

does it work?

okamitok

Nope the LED turns on on the sensor and it just continues to press towards the bed.

Here is a copy of my config.g

https://pastebin.com/Yadsckyx

And here is the Duet version:

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Firmware Name:	RepRapFirmware for Duet WiFi
Firmware Electronics:	Duet WiFi 1.0
Firmware Version:	1.19.2 (2017-09-01)
WiFi Server Version:	1.19.2
Web Interface Version:	1.19

dc42

Sounds like a configuration or wiring problem then. Duet Web Control displays the Z probe reading on the Control and Print Status pages. The reading should rise to about 535 when you hold a target close to the underside of the sensor so that the LED illuminates. Please check this. Also please post your config.g file.

okamitok

I linked the config.g up above: https://pastebin.com/Yadsckyx

I do get the correct readings but for some reason when it goes to actually probe it ignores the signal.

I did the following:

G92 Z0
G30 S-1

Then took the reading and used the value for the Z parameter in G31 command in config.g

okamitok

Not sure if it makes a difference but I have a black heater bed with a 6mm glass plate on top, but as mentioned the G30 S-1 command worked fine.

dc42

Just to be clear: are you saying that if you position the head about 5mm above the bed and run G30 S-1 then the probe stops when the LED comes on; but if you position the head 5mm above the same point and send G30 without the S-1 then it doesn't stop? Please check this.

okamitok

So I just did a test because nothing was working again even with S-1.
If I lay a piece of paper on the glass, then it probes every time no problem, it isn't probing to the exact same spot it's quite a bit above the paper but the probe stops every time without crashing.

Which is weird because I see the numbers go 464 and then 538 with only the glass bed but it wont stop. Where as with the paper it does the same thing but it stops.

SolarOH

I wanted to piggyback onto this as i have the same issue. (DuetWIFI coreXY build with IR probe, X and Y endstops are on high ends of build plate i.e 300, 290)

I was running 1.19 and was having connectivity issues to the webcontrol UI, but no issues with homing.

I updated just the other day to 1.20, and when i ran homeall, x and y homed, then z crashed to the bed.

So i recalibrated my z probe per the wordpress article, and the z probe was triggering as expected at the same value i had set before in G31. I tested G30 S-1, AND G30 both probed the bed and stopped before a crash.

My thought is that in the release notes there was mention of adding S2 to the M574 section, but doing that just caused the x and y to crash, never getting to Z.

Below is my config.g and homeall.g files, maybe someone can shed some light on this for me.

–---Config.g:-------

; Configuration file for testing Duet Ethernet and Wifi

; Communication and general
M111 S0 ; Debug off
M550 PHC300 ; Machine name and Netbios name (can be anything you like)
M551 Pcheats5 ; Machine password (used for FTP)
;*** If you have more than one Duet on your network, they must all have different MAC addresses, so change the last digits
M540 P0xBE:0xEF:0xDE:0xAD:0xFE:0xED ; MAC Address

;*** Networking - Enable for both WiFi and Ethernet boards.
M552 S1 ; Turn network on

;*** Ethernet networking: Adjust the IP address and gateway in the following 2 lines to suit your network
M552 P10.10.10.250 ; (0 = DHCP)
M554 P10.10.10.1 ; Gateway
M553 P255.255.255.0 ; Netmask

M555 P2 ; Set output to look like Marlin
G21 ; Work in millimetres
G90 ; Send absolute coordinates...
M83 ; ...but relative extruder moves

; Disable Fan 1 thermostatic mode
M106 P1 H-1

; Axis and motor configuration
M569 P0 S0 ; Drive 0 goes forwards
M569 P1 S0 ; 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
M574 X2 Y2 Z0 S0 ; set endstop configuration (all endstops at high end, active high)
;*** The homed height is deliberately set too high in the following - you will adjust it during calibration
M667 S1 ; switch to CoreXY mode
M208 X0 Y0 Z0 S1 ; Set axis minima
M208 X290 Y240 Z270 S0 ; Set axis maxima
M666 X0 Y0 Z0 ; put your endstop adjustments here, or let auto calibration find them
M350 X16 Y16 Z16 E16:16 I1 ; Set 16x microstepping with interpolation
M92 X80 Y80 Z400 ; Set axis steps/mm
M906 X500 Y500 Z500 E1120 I40 ; Set motor currents (mA) and increase idle current to 40%
M201 X1500 Y1500 Z1000 E1000 ; Accelerations (mm/s^2)
M203 X1000 Y1000 Z200 E3600 ; Maximum speeds (mm/min)
M566 X1200 Y1200 Z1200 E1200 ; Maximum instant speed changes mm/minute

; Thermistors
M305 P0 T100000 B3950 R4700 H30 L0 ; Put your own H and/or L values here to set the bed thermistor ADC correction
M305 P1 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set first nozzle thermistor ADC correction
M305 P2 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set 2nd nozzle thermistor ADC correction

M570 S180 ; Hot end may be a little slow to heat up so allow it 180 seconds

; Adjustments for J-heads used as dummy heaters on test rig
M307 H0 A250 C140 D5.5 B1
M307 H1 A250 C140 D5.5 B0
M307 H2 A250 C140 D5.5 B0

M557 X0:250 Y0:225 S25 ;mesh grid probe pattern

; Fans
M106 P1 S-1 ; disable thermostatic mode for fan 1

; Tool definitions
M563 P0 D0 H1 ; Define tool 0
G10 P0 S0 R0 ; Set tool 0 operating and standby temperatures
;*** If you have a single-nozzle build, comment the next 2 lines
;M563 P1 D1 H2 ; Define tool 1
;G10 P1 S0 R0 ; Set tool 1 operating and standby temperatures
M92 E837:837 ; Set extruder steps per mm
M143 H1 S290 ;set max hot end temp
M307 H1 A576.4 C196.8 D6 B0 S1 ;Set PID values for hot end
M143 H0 S125 ;set max bed temp
M307 H0 A146.6 C693.4 D9 B0 S1 ;Set PID values for Bed Heater

; Z probe and compensation definition
;*** If you have a switch instead of an IR probe, change P1 to P4 in the following M558 command
M558 P1 X0 Y0 Z1 ; Z probe is an IR probe and is used for homing Z axis
G31 Z1.5 P500 ; Set the zprobe height and threshold (put your own values here)

;*** If you are using axis compensation, put the figures in the following command
M556 S78 X0 Y0 Z0 ; Axis compensation here

;M208 S1 Z-1.95 ; set minimum Z

T0 ; select first hot end

-------Homeall.g–-------

G91 ; relative mode
G1 S1 X340 Y340 F3000 ; course home X or Y
G1 S1 X340 ; course home X
G1 S1 Y340 ; course home Y
G1 X-4 Y-4 F600 ; move away from the endstops
G1 S1 X10 ; fine home X
G1 S1 Y10 ; fine home Y
; Z homing section follows for IR Z probe
G1 X-30 F3000 ; X offset to get z probe to bed
G1 S1 Z-400 F500 ; course home Z
G1 Z2 F500 ; move away from the Z Probe
G1 S1 Z-4 F100 ; fine home Z
G90 ;back to absolute mode
G92 Z1.5 ;tell printer that it is at Z=1.5 (trigger height of z probe during homing)