Grinding on Z axis

CNC Machines Shapeoko 5 Pro
1

On my Shapeoko 5 Pro I have a problem that’s driving me nuts.

  1. I initialise the machine.
  2. The correct bit gets secured in the spindle (80mm VFD).
  3. Machine moves to the bitsetter.
  4. Z axis moves up after bitsetter and there is a horrible grinding noise when it’s close to / at the top of the axis.
  5. Zero height is not correct.
  6. When I redo the whole procedure, the zero height is suddenly correct. But then the roughing carve goes well, except for the finishing pass to cut in the air, because after tool change it goes to the bitsetter again and does the grinding again…

I checked the Z axis limiter switch and the red light shines when I hold a metal bar underneath, so seems to be properly working(?).

Is my gas strut faulty like the person from this thread?

2

Start testing this by removing the gas strut (be sure to have a block of foam handy to put under your Z-axis before powering down).

If that fixes it or no, let the folks at support@carbide3d.com know about this and they will work through this with you.

3

Just tested three times in a row (shutting down the machine in between) without the gas strut. No problem whatsoever! So the strut it definitely the problem. Will write at support@carbide3d.com. Thanks Will.

In the meantime; can I run the machine without the strut or better not?

4

Yes, the machine may be used w/o a gas strut — just put a block of foam or wood under the Z-axis before powering down to catch it.