@fred-y Thanks for this idea - it seems to work. I made this:

using the two holes on the motor side of the extruder. This leaves a nice gap on the molex connector side for the plug to fit properly.
This is how it looks in situ:

I am using the default sensitivity on a v3 smart effector, and found that it needed an extra -0.04 on the probe offset. Seems to work well though - a 19 point G32 gave a 0.010 fit.

The mount pictured was printed with the new setup - I was fine tuning the thread diameter - 12.3mm was good for me. I havent pushed the new setup yet - seems promising though.

@3dmntbighker I have put a new version on thingiverse, 3649565. I have increased the play, and made the bolts screw in from the side. This is easy for the bottom bearing, but you need a 7mm bolt for the upper bearing to fit between the vertical bolts. Their spacing is determined by the holes on the PCB.

I have done more experiments with the gap between sensor and top bearing, and have concluded so far that a 5mm spacer is probably ok. I realised that my initial results were essentially single points for the max and min - with repeated runs, the picture is not so clear, but I think 5mm is better than no spacer.

The percentages I get are still high, but quite reproducible - for the 5mm spacer, the average is about 270%, with the min not below 259, and the max not above 287 on 4 runs of at least 500mm extrusion. The relationship between sensor distance and average percentage reported is very linear - I have 12 points in my dataset now, with a least squares linear fit r squared of 0.998. The slope is 23.0 - the average percentage increases by 23 for each mm of gap between the sensor and bearing surface.

@jay_s_uk I find the easiest thing is to set a minimum layer time. The cat on the left is 20sec minimum, and the middle one is 10sec minimum. To check that its the time not speed of printing, the one on the right is one of two printed together with 20sec minimum.

I have posted a design on thingiverse for mounting an Orbiter 2 extruder on the Smart effector. (https://www.thingiverse.com/thing:5239585)
The magballs are moved out by 12mm, but maintaining the 55mm arm separation so you don't need to alter the carriages. This is enough to give access to the whole 250mm bed of my kossel XL with the extruder mounted horizontally just above the hotend. A prototype in pla seems to work fine, with a 19 point G32 giving mean deviation around 0.02. Print quality seems really good, although still optimising (still using my old input shaping settings). Have now printed it in carbon fibre petg, which should be stiffer, but not sure if that is necessary.
Enjoy.

Have done a test print of the 693zz version in pla.
As you can see, the jaw tends to drop somewhat when the filament goes through. Do you think it needs some extra support? - maybe a plate that goes on the bottom? Or perhaps it would be better in petg? For my printing, I think the 4mm slots for the bearings could do with a tiny bit more tolerance. Great idea though - I am about to order a laser monitor on the strength of it.

Those changes seem to work OK

I used 0.1mm gap on each side of the bearings, and added 1mm to the base of the jaw to make the spring stronger. I didn't have room for washers, but the bearings rotate quite freely.

@3dmntbighker I have just put the files on thingiverse, 3618968

I have some preliminary results on the effect of changing the working distance of the sensor. The sensor Web page suggests 5 - 60mm for glossy surfaces, and 20-40mm for white paper. I printed some spacers to go between the top and middle sections of the indirect sensor, and checked the results after printing about 700mm of filament. I have been using A0, and 5mm measuring interval. With no spacer I got 72%(48), 149%(100), 243%(163) for min, average and maximum, normalised to average =100 in the brackets. With the 10mm spacer, I got 180(49), 370(100), 390(105). With a 15mm spacer, it was 472(97), 487(100), 505(103), and the 25mm spacer 575(81), 708(100), 749(106). I need to do more tests, but it looks like a longer working distance may be better - the 15mm spacer result is quite good. Perhaps this is worth investigating with direct sensing too.
I am still getting the sensor reported as v1 after sending M591 D0 A0, sometimes reverting to v2 after a number of M591 D0 s (it is a v2 sensor)

@dc42 have done some more tests using a 20x20x4mm cube with 100%fill, printed at 60mm /sec, then varying the layer height or width to achieve specific filament movement rates. I print the first layer at 10mm/sec, so checking after 100 mm gives a 'slow' baseline for each test, and the total is a little over 700mm. Under these conditions I have no hiccups or missed steps.
For me, the monitor works well with filament movements up to 1.3mm/sec (max/min within 10% of the average) , but for 1.5mm/sec and 2mm/sec, the max/min range becomes very wide, often going negative on the min side. I get similar results with and without a 5mm spacer, although the actual numbers are higher with the spacer as previously observed.
The total extrusion reported by the monitor is very close (usually within 1%) to that shown by dwc or the slicer, even when the extrusion rate is above 1.5mm /sec.
I have also started to note the error rates for the monitor reported by M122. For tests below 1.3mm/sec, frame errors are 2000-4000, and pol errors high(20000-30000). Above 1.3mm/sec, frame errors are 20000 - 30000, but pol errors are below 10000. I have also noticed that the error count is not zeroed when you start a new print - I have been doing a reset after each test to zero things up.

Have now done some rolling back and forwards. M226 pause from gcode works for me in 3.1.1 and 3.2b2, but not in 3.2b3 or 3.2b3.2. Pause and resume working from dwc in all versions.

I just got a stop error too. duet2wifi standalone. First time this has happened with b4.

27/02/2025, 16:12:59 	Error: Code 7 move error: info=-4.970e+10, seg: s=1940 t=2912 d=-49701994496.00 u=-1.7068e+7 a=0.0000e+0 f=18

27/02/2025, 16:16:37 	M122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 3.6.0-beta.4 (2025-02-11 09:50:40) running on Duet WiFi 1.0 or 1.01
Board ID: 08DAM-999TL-MQ4SD-6J9FD-3SJ6J-K593W
Used output buffers: 1 of 26 (24 max)
=== RTOS ===
Static ram: 24016
Dynamic ram: 68004 of which 12 recycled
Never used RAM 17140, free system stack 68 words
Tasks: NETWORK(1,ready,17.1%,183) LASER(5,nWait 6,1.3%,214) HEAT(3,nWait 5,0.1%,328) Move(4,invalid,2.7%,261) MAIN(1,running,78.8%,846) IDLE(0,ready,0.1%,29), total 100.0%
Owned mutexes:
=== Platform ===
Last reset 01:19:58 ago, cause: power up
Last software reset at 2025-02-25 11:50, reason: User, Gcodes spinning, available RAM 26092, slot 0
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00400000 BFAR 0xe000ed38 SP 0x00000000 Task MAIN Freestk 0 n/a
=== Storage ===
Free file entries: 9
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest read time 13.3ms, write time 18.7ms, max retries 0
=== Move ===
Segments created 451, maxWait 685715ms, bed comp in use: none, height map offset 0.000, hiccups added 0/79 (2.63ms), max steps late 1, ebfmin 0.00, ebfmax 0.00
Pos req/act/dcf: 65603.00/65475/-0.92 59572.00/59500/-0.29 67651.00/67588/0.19
No step interrupt scheduled
Driver 0: standstill, SG min 0
Driver 1: standstill, SG min 0
Driver 2: standstill, SG min 0
Driver 3: standstill, SG min 0
Driver 4: standstill, SG min 0
Driver 5: 
Driver 6: 
Driver 7: 
Driver 8: 
Driver 9: 
Driver 10: 
Driver 11: 
=== DDARing 0 ===
Scheduled moves 375305, completed 375265, LaErrors 0, Underruns [0, 0, 0]
Segments left 1
Code queue is empty
=== Heat ===
Bed heaters 0 -1 -1 -1, chamber heaters -1 -1 -1 -1, ordering errs 0
=== GCodes ===
Movement locks held by null
HTTP is idle in state(s) 0
Telnet is idle in state(s) 0
File is doing "G1 X-46.241 Y12.008 E.00958" in state(s) 0
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger is idle in state(s) 0
Queue is idle in state(s) 0
LCD is idle in state(s) 0
Daemon is idle in state(s) 0
Autopause is idle in state(s) 0
=== Filament sensors ===
Driver 11: pos 0.00, brightness 18, shutter 97, errs: frame 0 parity 0 ovrun 0 pol 0 ovdue 0
=== Network ===
Slowest loop: 203.29ms; fastest: 0.00ms
Responder states: HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)
HTTP sessions: 2 of 8
=== WiFi ===
Interface state: active
Module is connected to access point 
Failed messages: pending 0, notrdy 0, noresp 0
Firmware version 2.2.1
Module reset reason: Turned on by main processor, Vcc 3.38, flash size 4194304, free heap 39440
MAC address 5c:cf:7f:2c:24:6b
IP address 192.168.1.16
Signal strength -48dBm, channel 8, mode 802.11n, reconnections 0
Clock register 00002002
Socket states: 0 0 0 0 0 0 0 0code_text

@dc42 a 1hr print completed for me too - thanks for the fix. Print quality looks very nice too.

@dc42 I didnt check the exact time , but just under 40 min would be about right for me too.

@balajiramani Hi - sorry for the delay
here is my bed.g. I have a 250mm dia round bed

; Auto calibration routine for large delta printer
M561                    ; clear any bed transform

; If the printer hasn't been homed, home it
;if !move.axes[0].homed || !move.axes[1].homed || !move.axes[2].homed
  G28

; Probe the bed and do auto calibration
G1 X-70 Y-60 Z10 F6000        ; go to just above the first probe point
while true
  if iterations = 5
    abort "too many auto calibration attempts"
  G30 P0 X-70 Y-60 Z-99999
  if result != 0
    continue
  G30 P1 X-85 Y0 Z-99999
  if result != 0
    continue
  G30 P2 X-50 Y75 Z-99999
  if result != 0
    continue
  G30 P3 X0 Y85 Z-99999
  if result != 0
    continue
  G30 P4 X50 Y75 Z-99999
  if result != 0
    continue
  G30 P5 X85 Y0 Z-99999
  if result != 0
    continue
  G30 P6 X75 Y-50 Z-99999
  if result != 0
    continue
  G30 P7 X0 Y-85 Z-99999
  if result != 0
    continue
  G30 P8 X-40 Y-40 Z-99999
  if result != 0
    continue
  G30 P9 X-50 Y0 Z-99999
  if result != 0
    continue
  G30 P10 X-40 Y40 Z-99999
  if result != 0
    continue
  G30 P11 X0 Y50 Z-99999
  if result != 0
    continue
  G30 P12 X40 Y40.00 Z-99999
  if result != 0
    continue
  G30 P13 X50 Y0 Z-99999
  if result != 0
    continue
  G30 P14 X40 Y-40 Z-99999
  if result != 0
    continue
  G30 P15 X-4 Y-2 Z-99999
  if result != 0
    continue
  G30 P16 X4 Y-2 Z-99999
  if result != 0
    continue
  G30 P17 X0 Y4 Z-99999 S6
  if result != 0
    continue
 
  if move.calibration.final.deviation <= 0.03
    break
  echo "Repeating calibration because deviation is too high (" ^ move.calibration.final.deviation ^ "mm)"
; end loop
echo "Auto calibration successful, deviation", move.calibration.final.deviation ^ "mm"
G1 X0 Y0 Z150 F5000                ; get the head out of the way
M500
G28

@balajiramani I run delta calibration using the smart effector probe without any obvious problem, with residual error usually under 0.02. I normally don't need to use mesh compensation.

@dc42 When trying the new alpha4+3, I get "movement halted step timing error occurred (code 3) Please reset the controller"
Got same error with two different files. Duet2wifi standalone on a linear delta
M122 following error:

m122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 3.6.0-alpha.4+3 (2024-08-28 10:03:28) running on Duet WiFi 1.0 or 1.01
Board ID: 08DAM-999TL-MQ4SD-6J9FD-3SJ6J-K593W
Used output buffers: 3 of 26 (24 max)
=== RTOS ===
Static ram: 23360
Dynamic ram: 66712 of which 12 recycled
Never used RAM 16112, free system stack 112 words
Tasks: NETWORK(2,nWait 6,13.1%,222) HEAT(3,nWait 5,0.1%,328) Move(4,invalid,4.8%,266) MAIN(1,running,82.0%,832) IDLE(0,ready,0.0%,29), total 100.0%
Owned mutexes: WiFi(NETWORK)
=== Platform ===
Last reset 00:38:48 ago, cause: power up
Last software reset at 2024-08-24 14:15, reason: User, Gcodes spinning, available RAM 25120, slot 1
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00400000 BFAR 0xe000ed38 SP 0x00000000 Task MAIN Freestk 0 n/a
Error status: 0x00
Aux0 errors 0,0,0
MCU temperature: min 36.1, current 38.1, max 39.1
Supply voltage: min 24.1, current 24.3, max 24.7, under voltage events: 0, over voltage events: 0, power good: yes
Heap OK, handles allocated/used 99/2, heap memory allocated/used/recyclable 2048/60/0, gc cycles 0
Events: 0 queued, 0 completed
Date/time: 2024-08-28 21:43:15
Slowest loop: 213.94ms; fastest: 0.13ms
I2C nak errors 0, send timeouts 0, receive timeouts 0, finishTimeouts 0, resets 0
=== Storage ===
Free file entries: 9
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest read time 10.1ms, write time 0.0ms, max retries 0
=== Move ===
Segments created 495, maxWait 54217ms, bed comp in use: none, height map offset 0.000, hiccups added 7 (0.25ms), max steps late 0, ebfmin 0.00, ebfmax 0.00
Pos req/act/dcf: 66607.00/66935/-0.71 68379.00/68333/0.81 68571.00/68351/0.46
no step interrupt scheduled
Driver 0: standstill, SG min 0
Driver 1: standstill, SG min 0
Driver 2: standstill, SG min 0
Driver 3: standstill, SG min 0
Driver 4: standstill, SG min 0
Driver 5: 
Driver 6: 
Driver 7: 
Driver 8: 
Driver 9: 
Driver 10: 
Driver 11: 
=== DDARing 0 ===
Scheduled moves 242824, completed 242785, LaErrors 0, Underruns [0, 0, 0]
=== Heat ===
Bed heaters 0 -1 -1 -1, chamber heaters -1 -1 -1 -1, ordering errs 0
Heater 0 is on, I-accum = 0.3
Heater 1 is on, I-accum = 0.4
=== GCodes ===
Movement locks held by null
HTTP is idle in state(s) 0
Telnet is idle in state(s) 0
File is idle in state(s) 3
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger is idle in state(s) 0
Queue is idle in state(s) 0
LCD is idle in state(s) 0
Daemon is idle in state(s) 0
Autopause is idle in state(s) 0
Q0 segments left 17
Code queue 0 is empty
=== Filament sensors ===
check 6729139 clear 1019682
Extruder 0: pos 4.41, brightness 27, shutter 117, errs: frame 0 parity 0 ovrun 0 pol 0 ovdue 0
=== Network ===
Slowest loop: 21.17ms; fastest: 0.07ms
Responder states: HTTP(0) HTTP(1) HTTP(1) FTP(0) Telnet(0)
HTTP sessions: 1 of 8
=== WiFi ===
Interface state: active
Module is connected to access point 
Failed messages: pending 0, notrdy 0, noresp 0
Firmware version 2.1.0
MAC address 5c:cf:7f:2c:24:6b
Module reset reason: Turned on by main processor, Vcc 3.38, flash size 4194304, free heap 41984
WiFi IP address 192.168.1.16
Signal strength -46dBm, channel 4, mode 802.11n, reconnections 0
Clock register 00002002
Socket states: 5 0 3 3 0 0 0 0
28/08/2024, 21:42:39 	Error: Movement halted because a step timing error occurred (code 3). Please reset the controller.
28/08/2024, 21:08:45 	M32 "0:/gcodes/OrcaCube_225.gcode"
File 0:/gcodes/OrcaCube_225.gcode selected for printing

@dc42 the filled cube looks fine - thank you very much.
here is the m122, in case of interest. No hics or step errors

05/04/2024, 17:32:04 	m122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 3.5.0-rc.3+8 (2024-04-05 15:37:41) running on Duet WiFi 1.0 or 1.01
Board ID: 08DAM-999TL-MQ4SD-6J9FD-3SJ6J-K593W
Used output buffers: 3 of 26 (26 max)
=== RTOS ===
Static ram: 23256
Dynamic ram: 72916 of which 12 recycled
Never used RAM 12032, free system stack 114 words
Tasks: NETWORK(2,nWait 6,14.0%,193) HEAT(3,nWait 5,0.1%,328) Move(4,nWait 5,1.2%,258) MAIN(1,running,84.7%,850) IDLE(0,ready,0.0%,29), total 100.0%
Owned mutexes:
=== Platform ===
Last reset 00:43:32 ago, cause: software
Last software reset at 2024-03-05 21:23, reason: User, Gcodes spinning, available RAM 11272, slot 1
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0041f000 BFAR 0xe000ed38 SP 0x00000000 Task MAIN Freestk 0 n/a
Error status: 0x00
Aux0 errors 0,0,0
MCU temperature: min 27.3, current 28.5, max 35.2
Supply voltage: min 24.0, current 24.4, max 24.6, under voltage events: 0, over voltage events: 0, power good: yes
Heap OK, handles allocated/used 99/0, heap memory allocated/used/recyclable 2048/32/32, gc cycles 0
Events: 0 queued, 0 completed
Driver 0: standstill, SG min 0
Driver 1: standstill, SG min 0
Driver 2: standstill, SG min 0
Driver 3: standstill, SG min 0
Driver 4: standstill, SG min 0
Driver 5: 
Driver 6: 
Driver 7: 
Driver 8: 
Driver 9: 
Driver 10: 
Driver 11: 
Date/time: 2024-04-05 17:32:01
Cache data hit count 4294967295
Slowest loop: 213.37ms; fastest: 0.11ms
I2C nak errors 0, send timeouts 0, receive timeouts 0, finishTimeouts 0, resets 0
=== Storage ===
Free file entries: 10
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest read time 1.0ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 100, segments created 24, maxWait 672741ms, bed compensation in use: none, height map offset 0.000, max steps late 1, min interval 0, bad calcs 0, ebfmin 0.00, ebfmax 1.00
no step interrupt scheduled
Moves shaped first try 2394, on retry 6, too short 1623, wrong shape 2362, maybepossible 3
=== DDARing 0 ===
Scheduled moves 8376, completed 8376, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 4], CDDA state -1
=== Heat ===
Bed heaters 0 -1 -1 -1, chamber heaters -1 -1 -1 -1, ordering errs 0
Heater 0 is on, I-accum = 0.2
=== GCodes ===
Movement locks held by null
HTTP is idle in state(s) 0
Telnet is idle in state(s) 0
File is idle in state(s) 0
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger is idle in state(s) 0
Queue is idle in state(s) 0
LCD is idle in state(s) 0
Daemon is idle in state(s) 0
Autopause is idle in state(s) 0
Q0 segments left 0
Code queue 0 is empty
=== Filament sensors ===
check 4755950 clear 4423949
Extruder 0: pos 10.19, brightness 27, shutter 134, errs: frame 0 parity 0 ovrun 0 pol 0 ovdue 0
=== Network ===
Slowest loop: 206.77ms; fastest: 0.07ms
Responder states: HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)
HTTP sessions: 1 of 8
=== WiFi ===
Interface state: active
Module is connected to access point 
Failed messages: pending 0, notrdy 0, noresp 0
Firmware version 2.1beta6
MAC address 5c:cf:7f:2c:24:6b
Module reset reason: Turned on by main processor, Vcc 3.38, flash size 2097152, free heap 42348
WiFi IP address 192.168.1.16
Signal strength -50dBm, channel 13, mode 802.11n, reconnections 0
Clock register 00002002
Socket states: 0 0 0 0 0 0 0 0

@dc42 thank you very much - looking forward to testing it

@dc42 Probably not exactly - this is my current config.g

; Communication and general
M111 S0                             	; Debug off
M550 PKosselXL							; Machine name and Netbios name (can be anything you like)
M551 Preprap                        	; 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
;*** Wifi Networking
M552 S1									; Enable WiFi. Disabled for setup and testing. Enable once set up on your network.
M555 P0                           		; Set output to look like Reprap
M575 P1 B57600 S1						; Comms parameters for PanelDue
G21                                 	; Work in millimetres
G90                                		; Send absolute coordinates...
M83                                 	; ...but relative extruder moves

; Axis and motor configuration
M584 X0 Y1 Z2 E3:4						;explicitly assign drives
M569 P0 S0								; Drive 0 goes backwards - changed to backwards for robodigg clamps
M569 P1 S0								; Drive 1 goes backwards - "
M569 P2 S0								; Drive 2 goes backwards - "
M569 P3 S0								; Drive 3 goes backwards - changed for orbiter 1.5
M569 P4 S0								; Drive 4 goes backwards - orbiter 2.0
M84 S120								;set idle timeout to 120sec
;M574 X2 Y2 Z2 S1						; set endstop configuration (all endstops at high end, active high)
M574 X2 S1 P"xstop"
M574 Y2 S1 P"ystop"
M574 Z2 S1 P"zstop"
;*** The homed height is deliberately set too high in the following - you will adjust it during calibration
M665 L360.25 R173.990 H297.084 B120.0 X0.538 Y0.525 Z0.000
M666 X1.493 Y-1.213 Z-0.280 A-1.03 B-0.66		; put your endstop adjustments here, or let auto calibration find them
M579 X1.005 Y1.012 Z1.00		        	;correct x y z scaling
M350 X16 Y16 Z16 I1	    				; Set 16x microstepping with interpolation
M350 E16:16 I1								; Set exruder to 16x with interpolation
M92 X200 Y200 Z200						; Set axis steps/mm
M906 X1400 Y1400 Z1400 I0.6		; Set motor currents (mA) and increase idle current to 60%
M906 E850:850 I10							;current for orbiter
M201 X5000 Y5000 Z5000 E5000:5000			; Accelerations (mm/s^2)
M203 X20000 Y20000 Z20000 E7200:7200			; Maximum speeds (mm/min)
M566 X900 Y900 Z900 E300 P1			; Maximum instant speed changes mm/minute, switch on 2.03 jerk policy

; Thermistors and heaters

M308 S0 P"bedtemp" A"Bed temp" Y"thermistor" T100000 B4138      ; configure sensor 0 as thermistor on pin bedtemp
M950 H0 C"bedheat" T0                               ; create bed heater output on bedheat and map it to sensor 0
M307 H0 B0 S1.00                                    ; disable bang-bang mode for the nozzle heater and set PWM limit
M140 H0									;bed heater is heater 0 
M143 H0 S125
M308 S1 P"e0temp" Y"thermistor" T100000 B4725 C7.060000e-8 A"Extruder temp"  ; configure sensor 1 as thermister via e0temp
M308 S2 P"e1temp" Y"thermistor" T100000 B4725 C7.060000e-8 A"Cold end temp"  ; configure sensor 2 as thermister via e1temp
;M308 S1 P"spi.cs1" Y"rtdmax31865" A"Extruder temp"  ; configure sensor 1 as thermocouple via CS pin spi.cs1
;M308 S2 P"spi.cs2" Y"rtdmax31865" A"Test temp"		; configure sensor 2
M950 H1 C"e0heat" T1                                ; create nozzle heater output on e0heat and map it to sensor 1
M950 P2 C"e1heat"									; create output to switch lights
M307 H1 B0 S1.00                                    ; disable bang-bang mode for the nozzle heater and set PWM limit
M143 H1 S300                                        ; set temperature limit for heater 1 to 295C
M570 H1 S60											;cancel print 60min after extruder temp fault

; ****Fans
M950 F0 C"fan0" Q500                               ; create fan 0 on pin fan0 and set its frequency
M106 P0 S0 H-1                                      ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"fan1" Q2500                                ; create fan 1 on pin fan1 and set its frequency
M106 P1 S1 H1 T45                                   ; set fan 1 value. Thermostatic control is turned on
M950 F2 C"!Fan2+^exp.pb6" Q25000
M106 P2 S0 H-1 C"Extra cool"
; Tools
M563 P0 D0:1 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

; Tool definitions
;M563 P0 D0 H1 F0:2                     			; Define tool 0 with fan 0, fan 2 linked
;M563 P0 D0 H1 F0 									; tool 0 with fan 0 only
G10 P0 S0 R0                        				; Set tool 0 operating and standby temperatures
M567 P0 E1.00:1.00									; set mix ratio
M309 p0 S0.006										; set heater feed forward for tool 0
;*** 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 E458                        					; Set extruder steps per mm
M92 E667:667                        					; Set extruder steps per mm orbiter
M572 D0:1 S0.032											;pressure advance extruder 0 and 1
;M572 D1 S0.02										; pressure advance extruder 1
M207 S2.1 R0.0 F7200 Z0.05             		; firmware retraction setting

; Z probe and compensation definition
M558 P8 C"zprobe.in+zprobe.mod" R0.4 F1000 H5 A2 S-1		;Z probe smart effector
M672 S105:20:235									;set z probe sensitivity
;G31 P100 X0 Y0 Z-0.10								;probe offset for old smart effector
G31 P100 X0 Y0 Z-0.08								;probe offset for new smart effector 0.27 for petg 0.18 for pla try 0.1 for direct drive

													;laser filament monitor settings
M591 D0 P5 C"connlcd.encb" R01:300 E10 L0.45 S1 A1		;version for reprap3

;M955 P0 C"spi.cs3+spi.cs4" I64 S5000 R10							;accelerometer configuration

;*** If you are using axis compensation, put the figures in the following command
M556 S100 X0.05 Y0 Z0                  				; Axis compensation here
M593 P"zvd" F27 L0.10 S0							; Damp ringing at 27Hz
M376 H0											;taper mesh over 10mm
M501												;use override-config.g parameters
M208 S1 Z-0.2										; set minimum Z
M912 P0 S-2											;calibration mcu temperature reading
G28													;Home axes
M42 P2 S1											;lights on
;G29 S1												;load height map and activate mesh compensation
;M290 S-0.1											;current baby steps 
;
T0													; select first hot end

@balajiramani when I tried the 20x20x20 filled cube with IS disabled there was no debug output (although the y slope is still there).