I have a VFD, mounted on my Clausing 6913 lathe.

The VFD is mounted on an aluminum plate, which in turn is bolted to a
bracket, which is bolted to the lathe, with various metal parts and
metal screws.

The VFD has a ground lug, which I connected to the incoming cable.

I am pretty sure, though I will triple check tonight, that I have a
continuous ground path to my home panel and to the buried ground rod
outside.

I always thought that there was no problem with the VFD/lathe etc, but
that is only because I always wore rubber soled shoes (crocs, boots
etc).

Yesterday I ran it without shoes and I was unpleasantly "zapped" when
I touched the VFD or the metal lathe itself.

So my question is WTF. Even if the motor "leaks" current due to
coltage spikes, shouldn't the grounding take care of it?

My second question is what would you suggest doing. Just giving up on
the VFD and using a phase converter, or try to replace the 3 HP motor?
Anyone knows if the motors on 6900 series lathes are 182 frame?

In any case, my plan for tonight is

1) Check that I do have a continuous ground path from home ground rod
to the VFD
2) Measure the voltage of that leakage
3) Add one more single conductor green cable, from the VFD ground lug,
bolted to the body of the lathe.

Then I can think about what to do with this.

i