Servo deployed probe on Duet Maestro

Phaedrux

Ok, that should help things a bit. Change the direction of rotation for the Z axis driver in your config.g with the M569 command

https://duet3d.dozuki.com/Wiki/Gcode#Section_M569_Set_motor_driver_direction_enable_polarity_and_step_pulse_timing

The endstop switch could be repurposed for a Z max endstop switch for using in power loss recovery. See what I mean here:

https://duet3d.dozuki.com/Guide/Ender+3+Pro+and+Duet+Maestro+Guide+Part+5:+Upgrades/54#s212

Veti

you dont need to disconnect it. you can leave it conected if you want.

just you need to adjust your homeall and homez to use the probe instead of the endstop.
like you have done in the homeall.

Phaedrux

@Phaedrux said in Servo deployed probe on Duet Maestro:

Your homeall isn't using the probe at all at this point, still just the endstop. Trying to control the probing manually isn't going to work very well. Better to script it out in the homing file at this point.

If you want to continue to use the Z endstop, that's fine. Here's what I would add.
M402 ; retract the pin just incase
G91                     ; relative positioning
G1 H2 Z5 F6000          ; lift Z relative to current position
G1 H1 X-285 Y-155 F1800 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 X5 Y5 F6000       ; go back a few mm
G1 H1 X-285 Y-155 F360  ; move slowly to X and Y axis endstops once more (second pass)
G1 H1 Z-155 F360        ; move Z down stopping at the endstop
G90                     ; absolute positioning
G1 X105 Y150 Z5 F6000 ; move probe into position at bed center
M401 ; deploy the probe
G30 ; probe the bed
M402 ; retract probe
G1 X10 Y10 Z10 ; return to parked position

The homeall I showed uses both the endstop and the probe. You could use the endstop as a first fast pass followed by the probe. It's totally up to you how you want to use it.

Blacksheep99

Thanks to you both.

So my plan of attack now is to revert the homeall and home z such that they just use the zprobe.

I also need to modify the config.g to reverse the motor on Z

Agree?

Veti

yes that is correct

Blacksheep99

@Veti Do I take the Z endstop out?

; Endstops
M574 X1 S1 P"xstop"                             ; configure active-high endstop for low end on X via pin xstop
M574 Y1 S1 P"ystop"                             ; configure active-high endstop for low end on Y via pin ystop
M574 Z1 S1 P"zstop"                             ; configure active-high endstop for low end on Z via pin zstop

Veti

@Blacksheep99 said in Servo deployed probe on Duet Maestro:

M574 Z1 S1 P"zstop" ; configure active-high endstop for low end on Z via pin zstop

change this to
M574 Z1 S2 ; configure Z-probe endstop for low end on Z

Blacksheep99

@Veti said in Servo deployed probe on Duet Maestro:

M574 Z1 S2 ; configure Z-probe endstop for low end on Z

Same on the zprobe?

; Z-Probe
M574 Z1 S1 										; Set endstops controlled by probe
M950 S0 C"^zprobe.mod" 							; create servo pin 0 for BLTouch
M558 P8 C"^!zprobe.in" H150 F900 T6000 			; Set Z probe type to switch and the dive height + speeds
G31 P50 X-50 Y-8 Z1.5 							;Set Z probe trigger value, offset and trigger height
M557 X15:265 Y15:135 S20                        ; define mesh grid

Phaedrux

@Veti said in Servo deployed probe on Duet Maestro:

M574 Z1 S2

You only need the M574 for Z once. Delete the other instance using S1.

Unless you wanted to use it as a z max endstop, in which case you physically move the endstop to the high end of Z travel, and set M574 Z2 S1. Then you can create a separate homing macro for the times when you want to home Z at the high end. This is useful when you have a print on the bed after a power loss.

Blacksheep99

Thanks.

I think i've changed the config.g now.

The homeall is similar to how you modified it however when I home all it would need the probe in position prior to the bed moving.

This is as it is now.

M402 ; retract the pin just incase
G91                     ; relative positioning
G1 H2 Z5 F6000          ; lift Z relative to current position
G1 H1 X-285 Y-155 F1800 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 X5 Y5 F6000       ; go back a few mm
G1 H1 X-285 Y-155 F360  ; move slowly to X and Y axis endstops once more (second pass)
G1 H1 Z-155 F360        ; move Z down stopping at the endstop
G90                     ; absolute positioning
G1 X140 Y75 Z5 F6000 ; move probe into position at bed center
M401 ; deploy the probe
G4 P500
G30 ; probe the bed
M402 ; retract probe
G1 X10 Y10 Z10 ; return to parked position

Veti

@Blacksheep99 said in Servo deployed probe on Duet Maestro:

G1 H1 Z-155 F360 ; move Z down stopping at the endstop

remove that line

Blacksheep99

@Veti Done.

Home all throws an error

G28
Error: G0/G1: insufficient axes homed

Phaedrux

G1 X140 Y75 Z5 F6000 ; move probe into position at bed center

remove the Z5 from that line as well

My example expected the Z axis to be homed at that point, but since that isn't happening the Z move is causing an error. But since it's not being homed, it's already been raised 5mm and doesn't need that move again.

Veti

it would have been a lot easier if you had used the homeall that i posted at the beginning

Blacksheep99

@Veti said in Servo deployed probe on Duet Maestro:

it would have been a lot easier if you had used the homeall that i posted at the beginning

I can only apologise.

Blacksheep99

@Phaedrux said in Servo deployed probe on Duet Maestro:

G1 X140 Y75 Z5 F6000 ; move probe into position at bed center

remove the Z5 from that line as well

My example expected the Z axis to be homed at that point, but since that isn't happening the Z move is causing an error. But since it's not being homed, it's already been raised 5mm and doesn't need that move again.

That ran through and seems to be all good. I'm sure I'll have to tweak the trigger height etc. Thank you so much to both for your guidance and patience with me

Veti

@Blacksheep99 said in Servo deployed probe on Duet Maestro:

I can only apologise.

no problem. i hope this helped you a bit to understand the commands and what they do.

Blacksheep99

@Veti said in Servo deployed probe on Duet Maestro:

@Blacksheep99 said in Servo deployed probe on Duet Maestro:

I can only apologise.

no problem. i hope this helped you a bit to understand the commands and what they do.

Yes it's definitely improved my understanding. I will likely leave things for now. After a long day at work maybe a fresh mind tomorrow will allow me to get a first successful print.

dc42

To clarify one thing. It doesn't matter what the probe reads when it is retracted. What matters is that when it is deployed, it reads zero when not triggered, and 1000 when triggered.

However, if the probe does read 1000 when retracted, then you may need to ensure that there is a short delay between deploying the probe and starting the probing move, to give the probe time to deploy and the reading to drop to 0. One way of doing this is to use a G4 command in deployprobe.g after the M280 command.

Blacksheep99

Thanks @dc42 this has all really helped my understanding. I’ve massively appreciated all the help I’ve received.