Cura Script to Automatically Probe Only Printed Area

[Luke'sLaboratory]

Alright - I've made an improvement to the script, I have an extra-large machine and depending on how much of the bed I'm using at any given point, I can exceed the points-per-axis limitations of duet firmware (currently 21:21). It now will run the calculations, and if there are more than 21 points required, it converts over to using the P parameter instead of the S parameter, trying to honor the original requested spacing.

#!/usr/bin/python
"""
	Slic3r post-processing script for RepRap firmware printers which dynamically defines the mesh grid dimensions (M557) based on the print dimensions. 
{1}
Usage:
{1}
	Slic3r Settings:
	In Print Settings > Output Options
	1. turn no "Verbose G-code"
	2. in "Post-processing scripts" type the full path to python and the full path to this script
	e.g. <Python Path>\python.exe  <Script Path>\meshcalc.py;
{1}
	In Printer Settings > Custom G-code > Start G-code
	Make sure the start g-code contains the M557 command, and that you probe the bed and load the compensation map,  e.g.
	M557 X10:290 Y10:290 S20	; Setup default grid
	G29							; Mesh bed probe
	G29 S1						; Load compensation map
		
	Script Settings
	probeSpacing = 20 - change this to the preferred probe point spacing in M557
		
	Note: The minimum X and Y of the probed area is limited to 2 times the probeSpacing.
	This is so that prints with a small footprint will have a minimum 3x3 probe mesh
{1}
Args:
{1}
	Path: The path parameter will be provided by Slic3r.
{1}
Requirements:
{1}
	The latest version of Python.
	Note that I use this on windows and haven't tried it on any other platform.
	Also this script assumes that the bed origin (0,0) is NOT the centre of the bed. Go ahead and modify this script as required.
{1}
Credit:
{1}
	Based on code originally posted by CCS86 on https://forum.duet3d.com/topic/15302/cura-script-to-automatically-probe-only-printed-area?_=1587348242875.
	and maybe 90% or more is code posted by MWOLTER on the same thread.
	Thank you both. 
"""
 
import sys
import re
import math
import os
 
probeSpacing = 20   		# set your required probe point spacing for M557
 
def main(fname):	
	print("Starting Mesh Calculations")
 
	try:
		_Slic3rFile = open(fname, encoding='utf-8')
	except TypeError:
		try:
			_Slic3rFile = open(fname)
		except:
			print("Open file exception. Exiting.")
			error()
	except FileNotFoundError:
		print('File not found. Exiting.')
		error()
		
	lines = _Slic3rFile.readlines()
	_Slic3rFile.close()
 
	linesNew = calcBed(lines)
 
	_Slic3rFile = open(fname, "r+")
	_Slic3rFile.seek(0)                       
	_Slic3rFile.truncate()
	for element in linesNew:
		_Slic3rFile.write(element)
	_Slic3rFile.close()
	
	return
 
def error():
	# remove the next 2 lines to close console automatically
	print("Press Enter to close") 
	input()
	sys.exit()
 
def calcBed(lines):
	bounds = findBounds(lines)
	bed = findBed()
 
	for axis in bounds:
		if bounds[axis]['max'] - bounds[axis]['min'] < bed[axis]:
			print(f'Success: {axis} mesh is smaller than bed')
			
		else:
			print('Error: Mesh is larger than bed. Exiting.')
			error()
 
		for limit in bounds[axis]:
			if limit == 'min':
				if (bed[axis]) - bounds[axis][limit] > 0: 
					print(f'Success: {axis} {limit} coordinate is on the bed.')
				else:
					print(f'Error: {axis} {limit} coordinate is off the bed. Exiting.')
					error()
 
			if limit == 'max':
				if (bed[axis]) - bounds[axis][limit] > 0: 
					print(f'Success: {axis} {limit} coordinate is on the bed.')
				else:
					print(f'Error: {axis} {limit} coordinate is off the bed. Exiting.')
					error()
	return fillGrid(bounds, lines)
	
def findBed():
	bed = {
		'X': 0,
		'Y': 0,
		}
 
	bedCorners = os.environ.get("SLIC3R_BED_SHAPE")
	maxXY = bedCorners.split(',')[2].split('x')
	bed['X'] = int(maxXY[0])
	bed['Y'] = int(maxXY[1])
	print(bed)
 
	return bed
 
def findBounds(lines):
	bounds = {
		'X': {'min': 9999, 'max': 0},
		'Y': {'min': 9999, 'max': 0},
		}
	
	parsing = False
	for line in lines:
		if "move to next layer (0)" in line:
			parsing = True
			continue
		elif "move to next layer (1)" in line:
			break
 
		if parsing:
			# Get coordinates on this line
			for match in re.findall(r'([YX])([\d.]+)\s', line):
				# Get axis letter
				axis = match[0]
 
				# Skip axes we don't care about
				if axis not in bounds:
					continue
 
				# Parse parameter value
				value = float(match[1])
 
				# Update bounds
				bounds[axis]['min'] = math.floor(min(bounds[axis]['min'], value))
				bounds[axis]['max'] = math.ceil(max(bounds[axis]['max'], value))
				
	# make sure the bounds are at least 2 x Probe Point Spacing, for small prints.
    # also, make sure that the maximum amount of points isn't exceeded.
	if parsing:
		global probeSpacing
		
		for axis in bounds:
			spacing = (bounds[axis]['max'] - bounds[axis]['min'])/2
			if spacing < probeSpacing:
				probeSpacing = spacing
 
	print("Bounds are: " + str(bounds))			
	return bounds
 
 
def fillGrid(bounds, lines):
    #Check the quantity of points - cannot exceed 21points per axis, otherwise will throw error and ruin print by not running a mesh
    X_points=(bounds['X']['max']-bounds['X']['min'])/probeSpacing
    Y_points=(bounds['Y']['max']-bounds['Y']['min'])/probeSpacing
    if X_points>21 or Y_points>21:
     Points=True
	 #basically, if its over 21, just use 21, if not, round up, keeping roughly the same spacing for the non-affected axis
     if X_points>21: X_points = 21 
     else: X_points = math.ceil(X_points)
     if Y_points>21: Y_points=21
     else:Y_points = math.ceil(Y_points)
     print('With your required print footprint, you\'ll exceed 21 points on either axis, changing to point based. Your new point grid is {}:{} points'.format(X_points,Y_points))

    else: 
     Points=False
        
    if Points == True:
        # Fill in the level command template
        gridNew = 'M557 X{}:{} Y{}:{} P{}:{}'.format(bounds['X']['min'], bounds['X']['max'],bounds['Y']['min'], bounds['Y']['max'], X_points, Y_points)
    else:
	    # Fill in the level command template 
	    gridNew = 'M557 X{}:{} Y{}:{} S{}'.format(bounds['X']['min'], bounds['X']['max'],bounds['Y']['min'], bounds['Y']['max'], probeSpacing)

	# Replace M557 command in GCODE
    linesNew = []
    for line in lines:
        if line.startswith('M557'):
            linesNew.append(re.sub(r'^M557 X\d+:\d+ Y\d+:\d+ S\d+', gridNew, line, flags=re.MULTILINE))
            print('New M557: ' + linesNew[-1])
        else:
            linesNew.append(line)
    return linesNew
  
if __name__ == '__main__':
	if sys.argv[1]:
		main(fname = sys.argv[1])
	else:
		print('Error: Proper Slic3r post processing command is python3')
		error()

[Baenwort]

Does this work for Deltas who don't have their M557 as a x and y coordinate?

[insertnamehere]

@Baenwort said in Cura Script to Automatically Probe Only Printed Area:

Does this work for Deltas who don't have their M557 as a x and y coordinate?

No it won't. But it could be modified.

[zapta]

@Luke-sLaboratory said in Cura Script to Automatically Probe Only Printed Area:

"move to next layer (0)"

Do we need to add to the prusaslicer gcode settings generation of layer markers or is there a setting to have it enabled automatically.

[zapta]

I setup my prusaslicer to use this script and it works very well. I looked for some time for per-print mesh automation and this one does the job. Thanks for sharing it.

The file version I am using is in the github link below. It uses utility classes to handle intervals and rectangles but otherwise it's the same flow. There are still a few TODOs but I am using it with my regular prints.

https://github.com/zapta/misc/blob/master/duet3d_automesh/duet3d_automesh.py

[Baenwort]

@insertnamehere

It would be great!

[zapta]

I cleaned up the python script. It now has command line flags that allow customization (set them in the slicer post processing command line).

https://github.com/zapta/misc/blob/master/duet3d_automesh/duet3d_automesh.py

I am very happy with the per-print quick partial meshing, getting good first layer without worrying about leveling. Ideally the slicers would provide the first layer's bounding box as place holders we can embed in gcode.

[tcj]

@zapta could you please change the script that it can handle negative coordinates in --meshable ?
This will make it usable for Delta printers, because
"For Cartesian printers, specify minimum and maximum X and Y values to probe and the probing interval. For Delta printers, specify the probing radius. If you define both, the probing area will be the intersection of the rectangular area and the circle. "
https://duet3d.dozuki.com/Wiki/Gcode#Section_M557_Set_Z_probe_point_or_define_probing_grid

Thank you

[zapta]

@tcj, I made the change. Can you give it another try?

https://github.com/zapta/misc/tree/master/duet3d_automesh

[tcj]

@zapta thank you for the effort, but ist does not work yet
only defining the default meshable area within the script (line 50) by

default="-185:185,-185:185"

works,
but when adding

<path to your python3> <path_to_the_duet3d_automesh.py file> --meshable "-185:185,-185:185"

to the Post-processing script, it fails

[zapta]

@tcj, try this syntax for the flags (notice the '=')

--meshable=-30:250,-3:280

[tcj]

@zapta

Thank you

[DK90]

@zapta said in Cura Script to Automatically Probe Only Printed Area:

--meshable=-30:250,-3:280

Hello, i have the following error when i am trying to ad the postprocess
can some one help me please?

Thanks

Post-processing script C:\Users\Dominic\AppData\Local\Programs\Python\Python36-32\python.exe C:\Program Files\Prusa3D\PrusaSlicer\duet3d_automesh.py file on file D:\2_Projekte\3D Druck\2_Modelle\28_R2D2_Did3D\R2D2_Did3D_SW_FullPack_h\STL_Final\zumdruckenbereit\Cube_PLA_Center foot_0.2mm_PET_2h24m.gcode failed.
Error code: 2
```~~~~

[tcj]

@DK90 the space in "Program Files" leads to this error
change it to

C:\Users\Dominic\AppData\Local\Programs\Python\Python36-32\python.exe "C:\Program Files\Prusa3D\PrusaSlicer\duet3d_automesh.py"

notice the "

[DK90]

@tcj said in Cura Script to Automatically Probe Only Printed Area:

C:\Users\Dominic\AppData\Local\Programs\Python\Python36-32\python.exe "C:\Program Files\Prusa3D\PrusaSlicer\duet3d_automesh.py"

Oh thank you now ot works
but wehn i start the print, there is now mesh leveling ....
where is my error?

Start G-Code

M83  ; extruder relative mode
M140 S[first_layer_bed_temperature] ; set bed temp

M190 S[first_layer_bed_temperature] ; wait for bed temp



; For automesh
     M557 TBD  ; parameters will be set automatically
     G28  ;home
     ;G29 S1 P"heightmap.csv"; Hoehenkarte Laden

M109 S[first_layer_temperature] ; wait for extruder temp
;G29 S1 P"heightmap.csv"; Hoehenkarte Laden


; Reinigungs Fahrt
G1 X-3.0 Y-10 F1500.0 ; go outside print area
G92 E0.0
G1 Z0
G1 E8 ; Purge Bubble
G1 X60.0 E9.0  F1000.0 ; intro line
G1 X100.0 E12.5  F1000.0 ; intro line
G92 E0.0

G-Code layer change setting

; Automesh: begin layer [layer_num]

[tcj]

@DK90 said in Cura Script to Automatically Probe Only Printed Area:

but wehn i start the print, there is now mesh leveling ....

and it never will without G29

this is a part of my start sequence

M140 S[first_layer_bed_temperature]
M104 S[first_layer_temperature]
M116; wait for temperatures to be reached
 
; For automesh
M557 TBD  ; parameters will be set automatically
G28 ; home
G29 ; mesh

[DK90]

oh yes that sounds good....that was my mistake...:D Thank you

[zapta]

@DK90, if you use panel due and prusaslicer (and maybe cura, didn't try), try to enable Support Remaining Time in the Printer Settings | General, tab. This will include M73 time markers in the gcode that which cause the post processing script to show remaining hours and minutes in the Standby fields of Panel Duet (ignore the '-' prefix).

This time estimation is much more consistent than the ones provided by Duet.

[DK90]

@zapta Thank you for the info. I will try it. That sound good.

[tcj]

@zapta I'm sorry to say that, but it does not work properly yet.
The script gives

M557 X-10:32 Y-10:32 P3:3

where it should deliver

M557 X-32:32 Y-32:32 P3:3

for a testcube in the middle of the bed with some mm of skirt

total dimensions +/- 21.xx mm