Adjusting dual y-axis

Kane

Adjusting dual y-axis
With my cnc I recently switch to FW 3.2.2 and by the way had to fit on my config.g and home configuration. I have a 2 motors belt driven y-axis with 2 independent endstops. Everything works just fine, but with the new already combined y axis, I can’t set a offset for one of the y-axis drives. If I measure after homing, I have an offset of about 1.1mm between both motors, so my gentry is not square. In RepRep FW2.. I solved the Problem before combining both axis, but know I am a little at a loss. Unlikely I didn’t found a solution in the forum jet.

Phaedrux

The instructions here for the Z axis and multiple endstops also applies to other axis with multiple motors and endstops.

https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors#Section_In_RepRapFirmware_Num_3

Kane

@phaedrux Thank you for your very fast response. But in the text you linked I couldn't find the answer of my problem, or I don't understand how to use G30 command for equaling my y-axis.

Kane

Did anyone else have a solution for my Problem?

here an abstract of my config.g file

...
M584 X0 Y1:3 Z2 ; Apply custom drive mapping Y-Axes with two drives
...
M574 Y1 S1 P"!ystop+!e0stop" ; configure active-high endstop for low end on Y via pin !ystop and e0stop Pin

homeall.g

G91 ; relative positioning
G1 H1 Z200 F1200 ; move quickly to Z axis endstop and stop there (first pass)
G1 Z-3 F150 ; go back a few mm
G1 H1 Z200 F100 ; move slowly to X axis endstop once more (second pass)

G1 H1 X-698 Y-355 F3000 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F6000 ; go back a few mm
G1 H1 X-698 Y-355 F360 ; move slowly to X and Y axis endstops once more (second pass)

G90 ; absolute positioning

nether M574 or G1 allow me to set an offset to drive 3 in example

Phaedrux

No in my link it was meant to show the endstop setup for homing.

I see now that you're actually wanting to add an offset to one motor of the combined axis.

Can you just change the physical position of the endstop or striker to change where it triggers?

Kane

@phaedrux I thought I could do this in the software. Never mind i try to solve this hardware wise.

Phaedrux

Well you could do it in software by using the older method from RRF2 of splitting the Y axis into separate axis for each motor and then homing them and adjusting the position of one of them before re-combining into the Y axis.

The RRF2 method is also described in that link above.

Kane

@phaedrux Ok, so I will use my old method.

Here the code from RRF2

|config.g
M584 X0 Y1 Z2 U3
M574 X1 Y1 U1 S0 ; Set active low endstops
M574 Z2 S0 ; Set active high endstops

|homeall.g
G91 ; relative positioning
.... ;Z-axis stuff
G1 S1 Y-1500 U-1500 F2400 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 Y+10 U+10 F2400 ; go back a few mm
G1 S1 Y-1500 U-1500 F300 ; move slowly to X and Y axis endstops once more (second pass)
G1 U+0.9 F100 ; move only U 0.9mm back so achieve squareness
M584 Y1:3 P3 ;combine 1 and 3 to Y
G90 ; absolute positioning

Here my Version for RRF3

|config.g
M584 X0 Y1 Z2 U3
...
M574 Y1 S1 P"!ystop" ; configure active-high endstop for low end on Y via pin !ystop
M574 U1 S1 P"!e0stop" ; configure active-high endstop for low end on U (second Y motor) via pin !e0stop

|homeall.g
G91 ; relative positioning
.... ;Z-axis stuff
G1 S1 Y-1500 U-1500 F2400 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 Y+10 U+10 F2400 ; go back a few mm
G1 S1 Y-1500 U-1500 F300 ; move slowly to X and Y axis endstops once more (second pass)
G1 U+0.9 F100 ; move only U 0.9mm back so achieve squareness
M584 Y1:3 ;combine drive 1 and drive 3 to one axis
M574 Y1 S1 P"!ystop+!e0stop" ; configure active-high endstop for low end on Y via pin !ystop and e0stop Pin

G90 ; absolute positioning

Kane

Sorry for my stupid post above, ist much easier than that. Fortunately my axis to adjust was y. So here my code from my homeall.g

G91             	                ; relative positioning
G1 H1 Z200 F1200 	; move quickly to Z axis endstop and stop there (first pass)
G1 Z-3 F150      	        ; go back a few mm
G1 H1 Z200 F100       	; move slowly to X axis endstop once more (second pass)

G1 H1 X-698 Y-355 F3000     ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F6000                ; go back a few mm
G1 H1 X-698 Y-355 F360       ; move slowly to X and Y axis endstops once more (second pass)

M584 Y1 U3 P4        ;split y axis 
G1 Y1.2 F100           ; drive y axis (drive 1) 1.2mm back
M584 Y1:3 P3          ;recombine drive 1 and 3 to y axis 

G90                     ; absolute positioning