M671 relative to what? nozzle or probe?

[thetazzbot]

I've searched and read the docs, it just says put the location of the lead screws, but it doesn't say relative to what.

So if I have this setup

[left lead screw]
o....X....\/..............................................................o

[right lead screw]
o.............................................................X....\/.....o

where : o = lead screw; X = probe, and \/ is nozzle.

Do I measure from center of lead screw to \/ or X and put that number in M671?

[jay_s_uk]

@thetazzbot its relative to X0 Y0 the coordinate system
You measure from the pivot point. So on my v2.4, the M671 co-ordinate is the point at where the gantry can pivot. On something with a moving bed where the bed is fixed and the only pivot point is the lead screws then it would be the centre of the screw.

[thetazzbot]

@jay_s_uk i know that much, that wasn't my question. from lead screw to nozzle or probe???

[thetazzbot]

@jay_s_uk this is a vertical moving bed with lead screws on left and right center.

[jay_s_uk]

@thetazzbot my answer would be it depends how you've setup your machine.
a typical machine has no offsets between the nozzle and the coordinate system so if you put your nozzle at X0, then it would be the distance between the nozzle and the centre of the lead screw.

[dc42]

@thetazzbot all measurements in RRF (axis minima, probe offsets, tool offsets, and M671 coordinates) are relative to the Head Reference Point (HRP). It's up to you to define where the HRP is. On a machine with just one tool it would normally be the tip of the nozzle.

[thetazzbot]

@dc42 Thank you

[thetazzbot]

@jay_s_uk Thank you