Wrong position after homing axes

Veti

@CoolM8 said in Wrong position after homing axes:

M564 H0 S1

i have pointed out to you earlier that this should not be in the config. why do you insist on having that in your config?

CoolM8

@Veti
I had M564 H0 in there, because i was used to be able to move the printhead without homed axes with the original printer hardware. When I remove completely, I cannot even home any of my axes, always getting: G0/G1: insufficient axes homed. This is also the case when I have M546 H1 S1.

homeX:
; Lift Z relative to current position
G91
G1 Z5 F6000
G90

; Move quickly to X axis endstop and stop there (first pass)
G1 X-210 F1200 S1

; Go back a few mm
G91
G1 X5 F6000
G90

; Move slowly to X axis endstop once more (second pass)
G1 X-210 F360 S1

; Lower Z again
G91
G1 Z-5 F6000
G90

homeY:
; Lift Z relative to current position
G91
G1 Z5 F6000
G90

; Move quickly to Y axis endstop and stop there (first pass)
G1 Y-210 F1800 S1

; Go back a few mm
G91
G1 Y5 F6000
G90

; Move slowly to X axis endstop once more (second pass)
G1 Y-210 F360 S1

; Lower Z again
G91
G1 Z-5 F6000
G90

homeZ:
; Lift Z relatively to current position
G91
G1 Z5 F6000 S2

; Back to absolute positioning
G90

; Go to first bed probe point and home the Z axis
G1 X100 Y100 F6000
G30

; Uncomment the following lines to lift Z after probing
;G91
;G1 Z5 F100
;G90

homeall:
; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool on Wed Apr 19 2017 22:18:05 GMT+0200 (W. Europe Daylight Time)

; Relative positioning
G91

; Lift Z
G1 Z5 F6000

; Course home X and Y
G1 X-210 Y-210 F1800 S1

; Move away from the endstops
G1 X5 Y5 F6000

; Fine home X and Y
G1 X-210 Y-210 F360 S1

; Absolute positioning
G90

; Go to first bed probe point and home Z
G1 X100 Y100 F1800

G30

Phaedrux

Thanks for providing the homing files. Makes it much easier.

@CoolM8 said in Wrong position after homing axes:

G0/G1: insufficient axes homed.

This is due to the Z moves to lift the print head above the bed before the axis are homed. M564 H0 is the brute force way of removing the check.

Trying to run homez before x and y are homed means that the G1 XY move you have in there has no reference point. X and Y must be homed before homing Z.

To correct the insufficient homed axis error without using M564 H0 you must add S2 to the Z moves in your homing files.

For example:

homeX:
; Lift Z relative to current position
G91
G1 Z5 F6000
G90

; Move quickly to X axis endstop and stop there (first pass)
G1 X-210 F1200 S1

; Go back a few mm
G91
G1 X5 F6000
G90

; Move slowly to X axis endstop once more (second pass)
G1 X-210 F360 S1

; Lower Z again
G91
G1 Z-5 F6000
G90

Would become:

homeX:
; Lift Z relative to current position
G91
G1 Z5 F6000 S2
G90

; Move quickly to X axis endstop and stop there (first pass)
G1 X-210 F1200 S1

; Go back a few mm
G91
G1 X5 F6000
G90

; Move slowly to X axis endstop once more (second pass)
G1 X-210 F360 S1

; Lower Z again
G91
G1 Z-5 F6000 S2
G90

Note the S2 on the Z move to raise and lower the print head.

The same would apply to the homey, homez and homeall files.

Here's a check list to go through to ensure that homing works properly.

0,0 places the nozzle on the front left corner of the print surface
if the endstop position is beyond 0,0 the axis minima should be negative, this can help account for any offset and keep parts properly positioned on the bed. This means if the nozzle is at the corner of the bed but still needs to move 10mm to the left to trigger the endstop, your axis minima for X is -10.
X+ moves to the right, Y+ moves to the back
homing direction moves towards the endstops
The probe should be positioned so that it is in the middle of the print surface before the G30 command
the XY probe offset and Z trigger height should be measured and inputted into G31 in config.g

CoolM8

Yes, if I add S2 to my Z-axis movement, I can again properly home X and Y.
But G30 still throws the same error when running homeZ or homeAll.

Phaedrux

@CoolM8 after you home x and y, what happens if you send this manually?

G90
G1 X100 Y100 F1800
G30

Phaedrux

Do you meet the points I mentioned?

CoolM8

Yes, everything is configured as you stated in your check list.

The command G1 X100 Y100 F1800 moves the print head to the center.
G30 throws the error:

G30
Error: G0/G1: insufficient axes homed

Phaedrux

That's really odd. And that's after x and y are homed? Do they show as homed?

Can you send G92 Z10 before you send G30?

Change Z10 for whatever appears to be close.to the actual z axis height at the time.

Veti

you made a lot of manual changes to the files from the configurator and changed the order of them.

i would suggest you input your parameters in the configurator again and replace all files with the generated ones.

CoolM8

@Phaedrux said in Wrong position after homing axes:

G92 Z10

If I run this before G30, no error is thrown. But the behavior with G30 is still the same: Strange movement in X and wrong placement in the end.

@Veti
Might be a good idea, I will try that tomorrow.

Phaedrux

Just occured to me... Do you have a deployprobe.g and retractprobe.g file in the /sys folder? If so delete them.

CoolM8

Well, that was it. Now it seems to be working correctly.

Funny, as longer as it takes to solve a problem, the simpler the solution is.

Thank you very much for your support.

Phaedrux

I don't know why it didn't occur to me sooner honestly.

This is why it helps to see every file from the sys folder at once. Get a complete picture.

If you'd followed vetis advice and torched the folder and redid the files you'd have the same result.

Veti

good catch. phaedrux

but out of curiosity. why did you put movement commands into your deployprobe.g ?

Phaedrux

@Veti It doesn't actually have to have any movement commands in it. I'm not sure exactly what the mechanism here is, but when the files exist when using a probe that doesn't require them you get weird behaviour.