Endstops Not Respected During Probing

CCS86

Is there some way to force the Maestro to respect endstop status during probing cycles (G30)? It seems to ignore them entirely.

jay_s_uk

@ccs86 endstops are only monitored during a homing move.
You could use M581 to remap them as triggers when not homing.
https://duet3d.dozuki.com/Wiki/Gcode#Section_M581_Configure_external_trigger

droftarts

@ccs86 probing should respect the machine limits set by M208, so I expect either those are wrong, or the probe offset is wrong. You’ll get a ‘point unreachable’ error if you have a probe point outside the machine limits.

Ian

CCS86

@droftarts said in Endstops Not Respected During Probing:

@ccs86 probing should respect the machine limits set by M208, so I expect either those are wrong, or the probe offset is wrong. You’ll get a ‘point unreachable’ error if you have a probe point outside the machine limits.

Ian

Hey Ian, axis minima are set correctly (M208 X0 Y0 Z0 S1), but the controller tried to drive into X negative space during a G30.

I can't see any way for an error in probe offset to cause this behavior. As far as the machine is concerned, it's just an arbitrary offset to the current position.

G29 respects the machine limits, and will give me point unreachable messages, while skipping those points. G30 however does not.

What happened was that I changed my print head design, and with it the probe offset. I have a 3-point leveling macro for adjusting my bed screws:

;probe for 3 point level

G91                     ; relative positioning
G1 H2 Z15 F6000          ; lift Z relative to current position
G28 XY

G1 X0 Y5 F4000        ; go to first bed probe point
G30                     ; home Z by probing the bed
G1 F2000

M558 A5 S-1

G30 P0 X21 Y2.67 Z-99999  
G30 P1 X174 Y2.67 Z-99999  
G30 P2 X86 Y177 Z-99999 S-1

M558 A1

G28 XY

M18 ;Disable Steppers

Old probe values: G31 X14 Y-18.5 Z2.13

New probe values: G31 P25 X21 Y-2.33 Z2.13

I forgot to update the macro for the first probing point to be equal to the X offset of the probe (ie X21 was still X14). The Duet slammed the carriage slammed into the X minimum.

CCS86

@jay_s_uk said in Endstops Not Respected During Probing:

@ccs86 endstops are only monitored during a homing move.
You could use M581 to remap them as triggers when not homing.
https://duet3d.dozuki.com/Wiki/Gcode#Section_M581_Configure_external_trigger

Seems like a good fallback, but it would be awesome for the control to respect the limits defined!

o_lampe

@ccs86 said in Endstops Not Respected During Probing:

M558 A5 S-1

~~Where did you see that S-1 is allowed and what does it change?~~

 For example, S-1 would force averaging.

There's also no 'P' parameter, which I thought was mandatory?

THX
Olaf

CCS86

@o_lampe said in Endstops Not Respected During Probing:

There's also no 'P' parameter, which I thought was mandatory?

THX
Olaf

That's not my full probe definition. It's just a modifier for the macro to take 5 averaged hits, instead of 1.

Phaedrux

Caution: the XY coordinates are permitted to be outside the normal printable bed area! This is intentional, because some printers (e.g. delta printers) benefit from probing areas not used for printing.

https://duet3d.dozuki.com/Wiki/Gcode#Section_G30_Single_Z_Probe

CCS86

@phaedrux said in Endstops Not Respected During Probing:

Caution: the XY coordinates are permitted to be outside the normal printable bed area! This is intentional, because some printers (e.g. delta printers) benefit from probing areas not used for printing.

https://duet3d.dozuki.com/Wiki/Gcode#Section_G30_Single_Z_Probe

Well, that explains it!

@dc42 Any chance we can add a flag to the G30 call to either respect or ignore axis limits?