Problems with Z axis

[Keith]

Hi @Wubster, welcome to the forums. Sorry you are having trouble and that it looks like you’ve been waiting a while for a response. It was a holiday weekend in the US, and I think in general a lot of us are less diligent at checking the forums on weekends. But anyway… Let me see if I can help…

@Wubster

I set bit to touch the work surface. GC reports Z=-0.52 In Z axis window I change distance to 10.0 and press Define Zero. Z axis motor hums quietly but does not move. GC reports Z=0.00. Repeatedly clicking Define Zero has same result. No movement.
I press Go to Zero. Motor hums but does not move! Repeatedly clicking Go to Zero has same result. No movement. Changed distance to 10. Still no movement with Go to Zero.

When you hit “Define Zero” you are telling GC that this is the location of the z-axis that it should consider zero. The axis should not move as a result of hitting “Define Zero” but the hum of the motor is likely the PID routine sorting out that it doesn’t actually need to move the axis. GC should report z=0.00 at this point. Pressing “Go to Zero” will not make the axis move at this point because you just told GC that the axis was at zero by hitting “Define Zero”

@Wubster

I press Save and Raise to Traverse. Bit raises 4mm. GC reports Z=-4.01. I’m not sure what to expect this button to do as I find no documentation for it. GCODE looks like it is supposed to raise the bit to the Safe Travel Height of 2mm.

I press Go to Zero. Bit raises 6mm to a point 10.3mm above work surface. GC reports Z=-10.31. (up 6.3) Why does it raise and not lower to zero?

This is sounding a bit like an encoder problem in the z-axis motor. I’m not the best one to help you troubleshoot if that’s the case, but I imagine you’ve been waiting to hear from someone on this.
Who did you purchase your kit from?

@Wubster

Changed distance to 2 and press Raise. Bit raised 3.9mm to a point 3.9mm above work surface. GC reports -4.07. (down 4.07)

I press Go to Zero and the bit raises 6.1mm to a point 10mm above the work surface. GC reports -10.53. (up 6.46)

Changed distance to 10 and press Lower. Bit lowered 13.6mm to a point 3.6mm into work surface. GC reports Z=5.07. (down 15.6)

Changed distance to 5 and press Raise. Bit raised 5.6mm to a point 2mm above work surface. GC reports -2.76. (up 7.83)

I press Go to Zero and the bit raises 5mm to a point 7mm above the work surface. GC reports -7.69. (up 4.93)

It looks like there’s a lot going on here. A couple questions for clarification…
–when you are saying that the bit is going into the work surface, are you running the router and actually drilling a hole?
–I am getting confused by the up and down in parentheses that you are putting at the end of your sentences [i.e.: "GC reports -10.53. (up 6.46)]. What are you trying to say there? My interpretation is that you are saying that GC is reporting the bit lowering, but it is actually going up by 6.46 mm.

So, my first troubleshooting suggestion is that you check all your cable connections for the z-axis to make sure they aren’t loose.
My next suggestion is that you do a systematic raising of the axis by 10mm at a time starting from the bit touching the work surface and pressing “Define Zero”. If the axis raises consistently using the raise button, check to see if the distance is always the same. It kind of sounds like your distance per revolution of the axis might be off, so trying this might help to figure that out. If it always raises the same, or nearly the same (as measured by you) then adjusting the distance per revolution might help.

As for GC reporting negative axis locations when actually raising the router, that is baffling. Please don’t take offense at this, but are you certain you are working only in metric (GC didn’t somehow switch to imperial somewhere in there)?

I’m not sure if you are able to post images yet (if not, reading a bunch more posts in the forum should get you over that), but if you can, pictures of your whole setup, your sled and z-axis setup, and if possible a video of the axis and what GC is reporting when you are trying to move the axis.
To give you an idea of the kind of video I am thinking of, here’s one I posted

Hopefully we can get this solved for you soon