Quote Originally Posted by Dave_stoke View Post
Thanks mate, so run the earth into the control box and connect to an earth point there?

Can I use hdmi for the spindle? I have a thicker rca shielded somewhere. I presume most of it is just signal wires?

Sent from my F8331 using Tapatalk
No. It's a 3ph motor in there so what you should have currently is just the 3 U V W power wires. I can't remember off the top of my head what the optimal core diameter is for the cable but depending what power spindle you have it isn't hard to figure out the max current and find out on google.

Quote Originally Posted by Richard View Post
Not on my machine. The bed is actually a big thick slab of cast iron, onto which is bolted an ali plate, which is drilled and tapped for tooling. It's basically sacrificial. As this is used machine, the plate had a few cuts in it and after transit and moving ect, it needed leveling.
Ah, I see. Very nice. Likelihood is it's a cast 5 series aluminium. In which case try drop your RPM by 20%. Have to feed a bit harder in that stuff.