BL Touch Installation what is Servo Pin?

engikeneer

@signpostman you will need to change your homing files to use a G30 probe command instead of the G1 H1 moves.

You can post your homing files here (copy paste the text and use the </> code snippet button when you post) and someone can help you change them.
Alternatively you could just create a new set of homing files that use the BLtouch using the RRF config generator tool.

You might also find some of the guide useful from the dozuki:
https://duet3d.dozuki.com/Wiki/Test_and_calibrate_the_Z_probe
https://duet3d.dozuki.com/Wiki/Using_mesh_bed_compensation (when you're ready to set up mesh comp)

SignPostMan

@engikeneer I created new file in the configuration tool but it didn't use the G30.
Could someone show me the changes needed?

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v3.3.0 on Sat Aug 21 2021 12:06:10 GMT-0400 (Eastern Daylight Time)
G91                       ; relative positioning
G1 H2 Z30 F6000           ; lift Z relative to current position
G1 H1 X-2305 Y-1305 F3000 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F6000         ; go back a few mm
G1 H1 X-2305 Y-1305 F180  ; move slowly to X and Y axis endstops once more (second pass)

G1 X250 Y650 F3000 ;move probe to centre of bed
G1 H1 Z-309 F360          ; move Z down stopping at the endstop (first pass)
G1 H2 Z5 F6000            ; go back a few mm
G1 H1 Z-20Y F180 		  ; move slowly to Z axis endstops once more (second pass)

G90                       ; absolute positioning
G92 Z0                    ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
G91                      ; relative positioning
G1 Z20 F1800              ; lift Z relative to current position
G90                      ; absolute positioning

engikeneer

@signpostman

This should do. Note that you'll also need to change your homez.g to match.

Also, if you still have your z endstop installed at the low end, be careful that you aren't going to crash into it when probing

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v3.3.0 on Sat Aug 21 2021 12:06:10 GMT-0400 (Eastern Daylight Time)

G91 ; relative positioning
G1 H2 Z30 F6000 ; lift Z relative to current position
G1 H1 X-2305 Y-1305 F3000 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F6000 ; go back a few mm
G1 H1 X-2305 Y-1305 F180 ; move slowly to X and Y axis endstops once more (second pass)

G90 ; absolute positioning
G1 X250 Y650 F3000 ;move probe to centre of bed

G30 ; probe bed

; Uncomment the following lines to lift Z after probing

G91 ; relative positioning
G1 Z20 F1800 ; lift Z relative to current position
G90 ; absolute positioning

Phaedrux

@signpostman said in BL Touch Installation what is Servo Pin?:

@signpostman I am getting this error

Are you using external drivers?

SignPostMan

@engikeneer I think that got it! Thanks!
Is there a use for the existing endstop on my Z axis? as a max height?

fcwilt

@signpostman said in BL Touch Installation what is Servo Pin?:

@engikeneer I think that got it! Thanks!
Is there a use for the existing endstop on my Z axis? as a max height?

I have a Z endstop at Z=0 (Z min) on all of my printers (as well a a Z probe).

It makes for simpler and quicker homing code.

For example to home with a Z probe you first have to home X and Y. To do that safely requires a bit of Z movement when homing X and Y.

With a Z endstop you can home Z first and then X and Y.

Frederick

Phaedrux

@signpostman said in BL Touch Installation what is Servo Pin?:

Is there a use for the existing endstop on my Z axis? as a max height?

Yes, you can move it to the Zmax position and use it in cases of power loss recovery where you need to home the z axis but can't use the probe because there is still a print on the bed. You need to set the Z max travel distance exactly using the probe to determine Z0 first in order to get it to be the right height to match the print position.

SignPostMan

It seems I still have a issue with the BL Touch. it does deploy and retract, but the Z axis keep descending without stopping after BL Touch triggered, the BL Touch keeps resetting but not stopping Z Descent.

SignPostMan

@phaedrux I think I will do that

fcwilt

@signpostman said in BL Touch Installation what is Servo Pin?:

It seems I still have a issue with the BL Touch. it does deploy and retract, but the Z axis keep descending without stopping after BL Touch triggered, the BL Touch keeps resetting but not stopping Z Descent.

Please copy-and-paste, using the </> tag, your current homeall.g file and and homez.g file.

Thanks.

Frederick

SignPostMan

@fcwilt ```
; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v3.3.0 on Sat Aug 21 2021 12:06:10 GMT-0400 (Eastern Daylight Time)

G91 ; relative positioning
G1 H2 Z30 F6000 ; lift Z relative to current position
G1 H1 X-2305 Y-1305 F3000 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F6000 ; go back a few mm
G1 H1 X-2305 Y-1305 F180 ; move slowly to X and Y axis endstops once more (second pass)

G90 ; absolute positioning
G1 X250 Y650 F3000 ;move probe to centre of bed

G30 ; probe bed

; Uncomment the following lines to lift Z after probing

G91 ; relative positioning
G1 Z20 F1800 ; lift Z relative to current position
G90 ; absolute positioning

fcwilt

@signpostman

Thanks.

And you say M401 and M402 work?

That would suggest that the signal from the BLTouch is not getting to the firmware.

Things to check:

wiring
BLTouch configuration commands (M950, M558 and G31)

Frederick

SignPostMan

@fcwilt M401 and M402 work, I wonder if having long cables could be the issue? My printer is huge and the cables are 5m long

fcwilt

@signpostman said in BL Touch Installation what is Servo Pin?:

@fcwilt M401 and M402 work, I wonder if having long cables could be the issue? My printer is huge and the cables are 5m long

5m - wow - that is rather long.

Did you verify that there is continuity on the wire that takes the signal from the probe back to the board?

Frederick

Phaedrux

The white wire is responsible for the trigger signal.

SignPostMan

@fcwilt I am able to trigger the probe with M401 and M402

SignPostMan

@phaedrux The probe is retracting and then resetting over and over but not stopping the z descent

fcwilt

@signpostman said in BL Touch Installation what is Servo Pin?:

@fcwilt I am able to trigger the probe with M401 and M402

That verifies that the control signal from the board to the probe is working.

There is another wire that from the probe to the board that carries the signal that tells the firmware the probe has been triggered.

Frederick

SignPostMan

@fcwilt The white wire?

fcwilt

@signpostman said in BL Touch Installation what is Servo Pin?:

@fcwilt The white wire?

I trust @Phaedrux - if he says it's the white wire it is - assuming you have a genuine BLTouch.

Frederick