Probe repeatability.

smaaash

Is there some function like M48 in Marlin? I’m running RRF 3.4.

droftarts

@smaaash M48 is not supported, but you can do the same thing with a macro. This one has been posted on the forum a few times; adjust the X and Y position for a point within the bed limits:

M291 P"Probe will be tested 10 times and return mean and standard deviation. Ok or Cancel?" R"WARNING" S3 ; User must click OK or cancel.
G28
M401
G30 P0 X100 Y100 Z-9999
G30 P1 X100 Y100 Z-9999
G30 P2 X100 Y100 Z-9999
G30 P3 X100 Y100 Z-9999
G30 P4 X100 Y100 Z-9999
G30 P5 X100 Y100 Z-9999
G30 P6 X100 Y100 Z-9999
G30 P7 X100 Y100 Z-9999
G30 P8 X100 Y100 Z-9999
G30 P9 X100 Y100 Z-9999 S-1
M402

If you create a file called M48.g in the /sys folder, and copy the above to it, you can call it by sending M48, if you really want to emulate Marlin!

Ian

oliof

@droftarts I cold coded a Macro that is more in line with M48 (except the star motion stuff) a couple weeks ago, I should test it and then publish (-:

dc42

@oliof please do!

oliof

@dc42 here goes. It still is buggy regarding position setting and misses the circular/star motion feature of Marlin's implementation (I have an even more buggy sub macro for that).

M48.g

Exerqtor

I've got one i made a while back too:

; M48.g  v3.0
; Called as response to M48
; Used to run probe repeatability test

 ;---/
; -/--/--/--/--/--/--/--/--/--/--/--/--/--/--/--/--
; THIS MACRO ONLY WORKS WITH RRF 3.5.0b1 AND LATER!!
;--/--/--/--/--/--/--/--/--/--/--/--/--/--/--/--/--
;-/

; ====================---------------------------------------------------------
; Settings section
; ====================

; Bed size
var bedX                = 350                                                  ; Input your beds X axis size here (used to calculate bed center)
var bedY                = 350                                                  ; Input your beds Y axis size here (used to calculate bed center)

; Nozzle clearance (gets overridden if you have global.Nozzle_CL)
var Clearance           = 5                                                    ; The "safe" clearance you want to have between the noszzle and bed before moving the printhead

; Don't touch anyting bellow this point!
; ====================---------------------------------------------------------
; Prep phase
; ====================

;Calculate bed center
set var.bedX = var.bedX / 2
set var.bedY = var.bedY / 2

if exists(global.Nozzle_CL)
  set var.Clearance = {global.Nozzle_CL}

var msg = "How many samples do you want to take? (3-32)"

; Ask to set sample amount
M291 S6 J1 R"Probe repeatability test" P{var.msg} L3 H32 F10

var Samples = {input}

set var.msg = "Doing " ^ var.Samples ^ " samples. Please wait..."

M291 S1 R"Probe repeatability test" P{var.msg} T5

M561                                                                           ; Clear any bed transform
M290 R0 S0                                                                     ; Reset baby stepping
M84 E0                                                                         ; Disable extruder stepper

if exists(global.sb_leds)
  set global.sb_leds = "homing"

; Lower Z currents
if fileexists("/sys/lib/current/z_current_low.g")
  M98 P"/sys/lib/current/z_current_low.g"                                      ; Set low Z currents
else
  M913 Z60                                                                     ; Set Z motors to 60% of their max current
 
; Lower Z relative to current position if needed
if !move.axes[2].homed                                                         ; If Z ain't homed
  G91                                                                          ; Relative positioning
  G1 Z{var.Clearance} F9000 H1                                                 ; Lower Z(bed) relative to current position	
  G90                                                                          ; Absolute positioning
elif move.axes[2].userPosition < {var.Clearance}                               ; If Z is homed and less than var.Clearance
  G1 Z{var.Clearance} F9000                                                    ; Move to Z var.Clearance

; ====================---------------------------------------------------------
; Home all axes
; ====================

; Make sure all axes are homed, and home Z again anyways
if !move.axes[0].homed || !move.axes[1].homed                                  ; If X & Y axes aren't homed
  ; Home X & Y axis
  M98 P"/sys/homex.g" Z{true} A{true}                                          ; Home X axis, pass param.Z since we allready lowered Z & A to indicate this is part of a homing sequence
  M98 P"/sys/homey.g" Z{ture} C{true}                                          ; Home Y axis, pass param.Z since we allready lowered Z & C since XY currents/speeds are also ok

; Home Z axis
M98 P"/sys/homez.g" Z{true} A{true}                                            ; Home Z axis, pass param.Z since we allready lowered Z & A to indicate this is part of a homing sequence

; ====================---------------------------------------------------------
; Probing code
; ====================

; Move to bed center
G90                                                                            ; Absolute positioning
G1 X[var.bedX] Y[var.bedY] F6000                                               ; Move to the center of the bed

; LED status
if exists(global.sb_leds)
  set global.sb_leds = "leveling"

M558 K0 F180 A1

var loopCounter = 0
while true
  G30 P{var.loopCounter} K0 Z-9999
  if iterations >= 1
    echo "Sample number " ^ {iterations} ^ ": " ^ {sensors.probes[0].lastStopHeight - sensors.probes[0].triggerHeight} ^ "mm"
  set var.loopCounter = iterations
  if iterations = var.Samples - 1
    G30 P{var.loopCounter} K0 Z-9999 S-1
    break

M558 K0 F300:180 A3

; ====================---------------------------------------------------------
; Finish up
; ====================

; Uncomment the following lines to lower Z(bed) after probing
G90                                                                            ; Absolute positioning
G1 Z{var.Clearance} F2400                                                      ; Move to Z var.Clearance

; Full currents
if fileexists("/sys/lib/current/xy_current_high.g")
  M98 P"/sys/lib/current/xy_current_high.g"                                    ; Set high XY currents
else
  M913 X100 Y100                                                               ; Set X Y motors to var.100% of their max current
if fileexists("/sys/lib/current/z_current_high.g")
  M98 P"/sys/lib/current/z_current_high.g"                                     ; Set high Z currents
else
  M913 Z100                                                                    ; Set Z motors to var.100% of their max current

set var.msg = "" ^ var.Samples ^ " samples complete, see console"

M291 S1 R"Probe repeatability test" P{var.msg} T5                              ; Test done message

; If using Voron TAP, report that probing is completed
if exists(global.TAPPING)
  set global.TAPPING = false
  M402 P0                                                                      ; Return the hotend to the temperature it had before probing

; LED status
if exists(global.sb_leds)
  set global.sb_leds = "ready"

dc42

Another useful one is to test for backlash on the delta printers, or tilt+backlash on most other types of printer with a moving X carriage. An outline is:

Move to X minimum Y centre
Move X to centre
Probe several times as per these M48 macros and report the resulting mean and SD
Move to X max
Move X back to centre
Probe several times as per these M48 macros and report the resulting mean and SD
Look for differences in the mean between the two sets of results

On deltas, also do the above using Y movements instead of X movements.