How to enter my own probing point for bed levelling?

deonholt

Firmware Name: RepRapFirmware for Duet 2 WiFi/Ethernet
Firmware Electronics: Duet WiFi 1.02 or later
Firmware Version: 2.05.1 (2020-02-09b1)
Printer: Ender 5 Pro: Bed: 220 x 220

Hi all and thanks for your help.
BL Touch offset from nozzle: X-49. Y10.5 (The probe is in front of the probe. Should it not also have been a negative number?)

I want to only use 5 probing points; four on each of the adjustment knobs and one in the middle. I cannot get the formula right for this. I have written down the XY coordinates for the nozzle positions.

TIA for your help.
Deon

Veti

see

https://duet3d.dozuki.com/Wiki/Gcode#Section_M557_Set_Z_probe_point_or_define_probing_grid

Instead of Using S parameter use the P parameter

fcwilt

Hi,

You need to create your bed.g file with the G30 commands which specify the XY points to probe.

For 5 points you will have 5 G30 commands. Note the S4 on the last G30 specifies that you have 4 adjustment screws.

G30 P0 X### Y### Z-99999 ; probe near adjusting screw #1
G30 P1 X### Y### Z-99999 ; probe near adjusting screw #2
G30 P2 X### Y### Z-99999 ; probe near adjusting screw #3
G30 P3 X### Y### Z-99999 ; probe near adjusting screw #4
G30 P4 X### Y### Z-99999 S4 ; probe center and report

You invoke bed leveling with G32.

Frederick

fcwilt

@Veti said in How to enter my own probing point for bed levelling?:

see

https://duet3d.dozuki.com/Wiki/Gcode#Section_M557_Set_Z_probe_point_or_define_probing_grid

Instead of Using S parameter use the P parameter

He wants to do bed leveling not mesh bed compensation.

Frederick

deonholt

@fcwilt said in How to enter my own probing point for bed levelling?:

@Veti said in How to enter my own probing point for bed levelling?:

see

He wants to do bed leveling not mesh bed compensation.

Thanks Frederick. This is exactly what I was looking for ... even though I did not use the purist language. I am learning though.

deonholt

@deonholt
One last question: What command activates the "Define Area for mesh grid compensation"?
I fill in numbers there but I cannot find the command to use those entered numbers?

fcwilt

@deonholt said in How to enter my own probing point for bed levelling?:

@deonholt
One last question: What command activates the "Define Area for mesh grid compensation"?
I fill in numbers there but I cannot find the command to use those entered numbers?

For Mesh Bed Compensation you use M557 to define the probing grid and G29 with the appropriate S parameter to create (S0) or load (S1) the height map.

Remember to use G30 to set the Z=0 Datum prior to creating or loading the height map.

Frederick

deonholt

@fcwilt said in How to enter my own probing point for bed levelling?:

@deonholt said in How to enter my own probing point for bed levelling?:

@deonholt
One last question: What command activates the "Define Area for mesh grid compensation"?
I fill in numbers there but I cannot find the command to use those entered numbers?

For Mesh Bed Compensation you use M557 to define the probing grid and G29 with the appropriate S parameter to create (S0) or load (S1) the height map.

Remember to use G30 to set the Z=0 Datum prior to creating or loading the height map.

Frederick

Thank you so much. I am learning all the way.

I got a pop-up message saying that M557 is not going to be used some time in the future. I opted for that because I cannot get my calculation for auto probing right.
Bed is: 220 by 220 and I want 9 probes. I want to start at X30:190 and Y30:190
Can you please assist in calculation this? I cannot find a tutorial on this.

Veti

ok for that see my post

deonholt

@Veti
Thanks. That I get. But I battle with the formula to get the correct radius.
This is what I have entered in config.g but it only probe 4 points with some errors:
557 X20:200 Y20:200 S90 ; define mesh grid

I got this error and don't have a clue on how to interpret it so I can fix it:

Warning: Skipping grid point (200.0, 200.0) because Z probe cannot reach it
6 points probed, min error -0.053, max error 0.175, mean 0.058, deviation 0.083
Height map saved to file heightmap.csv

I want the 4 corners to be the ones right above the adjusting knobs.

Thanks.

Veti

@deonholt said in How to enter my own probing point for bed levelling?:

X-49.

with an offset like that you M557 X minimum needs to be at least 49

so try
M557 X50:200 Y20:200 P3

deonholt

@Veti
Thanks. Will quickly do so. Something, to my experience, that the wiki lacks, is to tell newbies like myself: do we need to take the offset into consideration or not. That may be why I am battling. Will quickly try again and get back to you.
Thanks.

Veti

yes the M557 wiki should have a note on that.

deonholt

@Veti said in How to enter my own probing point for bed levelling?:

@deonholt said in How to enter my own probing point for bed levelling?:

X-49.

with an offset like that you M557 X minimum needs to be at least 49

so try
M557 X50:200 Y20:200 P3

I got this error:
Warning: Skipping grid point (200.0, 20.0) because Z probe cannot reach it
Warning: Skipping grid point (200.0, 110.0) because Z probe cannot reach it

Am I correct in saying that P3 tells it to do 3 probes in X & Y?

Thanks again.

Veti

@deonholt

ah sorry i got confused by the direction.

try
M557 X10:170 Y20:200 P3

Am I correct in saying that P3 tells it to do 3 probes in X & Y?

yes

deonholt

@Veti thanks.
On X it only went as far as 149.
I get the impression something is very wrong here. In what file do I set the bed size? X, Y & Z "maxima?"

Minute or what later ...
Bed maxima was 218. I changed it to 220 and it made 9 probes. Thanks for your help and patience.

M29 S? do I use to store the mesh and use it for the next print?

Thanks again. You're a Champ.

Veti

@deonholt

https://duet3d.dozuki.com/Wiki/Gcode#Section_G29_Mesh_bed_probe

G29 S1
loads the last mesh
add tp your slicer start code after G28

Phaedrux

@deonholt said in How to enter my own probing point for bed levelling?:

Y10.5 (The probe is in front of the probe. Should it not also have been a negative number?)

Yes, if 0,0 is in the front left corner and X+ is to the right and X- to the left and Y+ to the back and Y- to the front. Then if the probe i in front, it should have a negative offset.

Create yourself a diagram like this. It can help a lot to visualize the layout.

Bed Area.png

deonholt

@Phaedrux thank you so much for the diagram-idea. It is brilliant. Thanks again.

fcwilt

@Veti said in How to enter my own probing point for bed levelling?:

@deonholt

https://duet3d.dozuki.com/Wiki/Gcode#Section_G29_Mesh_bed_probe

G29 S1
loads the last mesh
add tp your slicer start code after G28

Strictly speakly G29 S1 loads the existing height map.

The "mesh" is what you define with M557 and is used to create the height map.

Frederick