Homing Issues

Hal

@phaedrux said in Homing Issues:

The trigger value in your G31 command is very low. Try 50 instead of 5.

So I have been setting my Z-trigger to do my Z-offset, I read that this is how the z-offset is defined?

If it is not then how is Z-offset set with the BLTouch?

I also see that I have these Errors (See below):

Error: Invalid Servo Index 0 in M280 command

Error: Homing failed

Error: G29: No Valid grid defined for be probing

These may be caused by all of the same thing, but I am not sure.

Any help would be appreciated, es[ecially for setting Z-Offset so I can fix these errors.

Thanks.

Hal

Just tried P50 and P80 to no avail. I still get the Z homing error.

Phaedrux

@hal said in Homing Issues:

G31 X0 Y0.0 Z0 P5

The X and Y values should be the distance from the BLTouch pin to the nozzle.

The Z value will need to be measured with a G30 S-1 command. I'll link to a tutorial on how to get that setup.

The P value is the trigger value. 5 is very low. I use 50 for the BLTouch.

The invalid servo index means something is wrong either with the M558 command and how you have things wired, or the command is wrong in your deployprobe.g and retractprobe.g macros.

Can you post those macros from the system folder?

Can you describe how you have the BLTouch wired up?

Does the BLTouch pin deploy and retract?

https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#Section_BLTouch

https://betrue3d.dk/bltouch-on-duet-wifi-configuratio-and-usage/

Hal

@phaedrux said in Homing Issues:

@hal said in Homing Issues:

G31 X0 Y0.0 Z0 P5

The X and Y values should be the distance from the BLTouch pin to the nozzle.

The Z value will need to be measured with a G30 S-1 command. I'll link to a tutorial on how to get that setup.

The P value is the trigger value. 5 is very low. I use 50 for the BLTouch.

The invalid servo index means something is wrong either with the M558 command and how you have things wired, or the command is wrong in your deployprobe.g and retractprobe.g macros.

Can you post those macros from the system folder?

Can you describe how you have the BLTouch wired up?

Does the BLTouch pin deploy and retract?

https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#Section_BLTouch

https://betrue3d.dk/bltouch-on-duet-wifi-configuratio-and-usage/

By the way thank you for helping me out and giving me suggestions.

I did try you suggestion of adjusting the trigger level and still had the error.

Yes my BLtouch deploys and retracts. I have been able to use the BLtouch with the Auto bed compensation button above the homing buttons, and it seems to work fine.

So it kinda leaves the software as the culprit.

M280 P3 S10 I1 is all I have in my deployprobe.g **I should also note that I do not call these macros anywhere I use the M401 and M402 commands instead.

M280 P3 S90 I1 Retractprobe.g

I followed the wiring guide from here:

http://www.folgerforum.com/t/walter-s-modifications-part-3-the-duet/1582

Thanks

Phaedrux

@hal M401 and M402 actually just call those macros, with the added benefit of letting the system keep track of the deployed and retracted state.
G30 calls the same macros to deploy and retract as well when doing a probe point.

It's possible that you have it wired in such a way that you must invert the signal for the servo. Try adding I1 to the M558 command in config.g, or removing the I1 from the M280 commands in the deploy and retract.

Can you repost what your homeall.g looks like now?

Hal

Okay so I removed the I1 from the deploy and retract and my bed almost rammed into my Build Plate. Thank goodness for emergency stop.

Phaedrux

Oh no! Sorry. I should have maybe mentioned that it's a good idea to test the BLTouch a good distance above the bed and manually trigger the pin by hand before it even gets close to the bed until you are sure it's working properly.

If it makes you feel any better I just did this tonight...

Caught the deployed pin on the end of the bed. The bed didn't drop before homeing Z because I mistakenly used M92 Z0 in a macro instead of G92 Z0. Instead of setting current height as Z=0 it set the z steps per mm to 0. No wonder the bed didn't drop. Oi.

Hal

It is all good I caught it before it even touched the bed. So I do not believe that I am Not Not inverted.

goodness I am not sure what this is.

Here is my homeall.g:

G28 X ;home x
G28 Y ;home y
G90
G1 X150 Y150 F4000
G30 ; Do a single probe to home our Z axis

Phaedrux

What happens if you manually issue a G30 command?

Hal

Probe deploys, bed moves up, hits probe, the probe retracts, then the z axis moves down a few mm for clearance. I believe this is the correct process.

I did have to home x and y before I could issue the G30 command

Phaedrux

But you still get a homing failed error along with the servo error?

Hal

@phaedrux said in Homing Issues:

But you still get a homing failed error along with the servo error?

Funny enough I did not, and i only get the servo error if i try to print.

Phaedrux

Are you manually calling M401 and M402 anywhere?

Phaedrux

Actually, now that you mention it, I was getting some servo error messages yesterday when I was testing stall detection as a z probe. I had commented out all of the M280 servo commands but I was still getting an error message occasionally. I didn't really think much of it. I looked for other M280 commands I might have forgotten but there were none.

Hal

@phaedrux said in Homing Issues:

Are you manually calling M401 and M402 anywhere?

Yes in my bed.g file

Hal

Well I figured out the M280 command error, it seems like I set my S3D to use P0 instead of P3, so made the change and boom no more M280 error.

I am still getting the homing errors and the M29 error.

maybe those errors are also causing my other errors, so here is my s3d start and stop process.

start gcode from s3d

M280 P3 S160 ; BLTouch alarm release
G4 P100 ; delay for BLTouch
G28 ; home
G29 ; auto bed leveling
G1 X0 Y5 Z0.2 F3000 ; get ready to prime
G92 E0 ; reset extrusion distance
G1 X250 E20 F600 ; prime nozzl

end gcode from s3d

M104 S0 ; turn off extruder
M140 S0 ; turn off bed
G28 X Y ; home x and y axes
M84 ; disable motors

thanks for any help.

Phaedrux

The M29 error is probably from having too many points in the grid. Try a higher s value and see if it will let you run it.

Phaedrux

Actually it looks like you haven't defined a mesh grid in your config.

Hal

should I even have that much in here as the Bed.g file should be called, or is that invoked from S3d?

Hal

alright down to 1 error homing error is still happening but auto bed leveling is running as expected.

I invoked the Bed.g file using M32 command.

maybe my issue is in the bed.g file now.

Thanks