Squaring a dual Y Axis CNC

Storm

Hi,
I have a CNC that isn't cutting square which I think started when I switched to dual Y axis end stops.
I presume they are not quite level despite both being pushed to the front of the machine as far forward as they can be.
Is there a way to account for the offset in GCode or will I physically have to keep moving one of the endstops before I get it right?
I see there is an M666 command to adjust an endstops offset but this seems to be for Delta machines.

jay_s_uk

You need to split the axis during homing, apply the offset and then rejoin them.
There's no M666 for normal endstops currently

Nightowl

I'm not sure if what I'm doing resolves your issue, but I use dual Y axis end stops I've configured them like this:

; Endstops
M574 X2 S1 P"io8.in"          	; configure switch-type (e.g. microswitch) endstop for high end on X via pin io8.in
M574 Y2 S1 P"io6.in+io5.in"	; configure switch-type (e.g. microswitch) and dual self-squaring high ends on Y1 via pin io6.in and on Y2 via pin io5.in
M574 Z2 S1 P"io2.in"          	; configure switch-type (e.g. microswitch) endstop for high end on Z via pin io2.in

I know it works because, when the machine was powered down, I accidentally moved one of the Y axes. When I then homed it, the machine realigned the Y axes and it's square again.

I hope this helps.

deckingman

@storm If you have multiple motors, and if you have multiple end stops (one per motor) and if you use RRF 3, then you can do it using M574.

jay_s_uk

@deckingman you can't apply an offset if the endstops aren't in exactly the same place. only way is back to old school RRF2 methods and split the axis into Y and U

deckingman

@jay_s_uk said in Squaring a dual Y Axis CNC:

@deckingman you can't apply an offset if the endstops aren't in exactly the same place. only way is back to old school RRF2 methods and split the axis into Y and U

Ah yes - I've should have read the OP's first post properly. My bad.

Storm

@jay_s_uk Thanks for this. I tagged it on the the end of my Y Homing and it works great.

Storm

Here's the code I used if anyone comes across this post in the future

M584 Y1 U2 P4 ;Separate Y Axis into Y&U and show U axis on UI
M564 S0 H0 ;Allow movement without homing as U axis not homed
G1 U2 ;Move right hand side of Y axis 2mm from endstop
M564 S1 H1 ;Enforce axis minimums and maximums and only allow movement after homing
M584 Y1:2 P3 ;Rejoin Y axis and hide U from UI