Shielding is shielding+ More makes only one difference is that it costs a lot more. Copper is no better than any other non ferrous metal. Any foil shielded wire is shielded 100% whereas braid can lose it’s shielding capabilities when kinked. Wire shielding does little to nothing for line noise from fluorescent lights and motors, that’s where the chokes come in or even better electronic line noise filters. Shielding is there to prevent EMI from RF.
Who still uses fluorescent lighting? 
LED’s are the bomb!
Yes your right, what I meant to say was stranded wire as solid core wouldn’t work in this situation. And yes on the LED’s I’ve switched all my lighting to LED.
LED drivers can produce some EMI as well - I purchased a new machine from CNC for newbies and this problem began almost immediately afterward. I disconnected the X controller and blew it out with the exhaust side of a shop vac - not a compressor! Worked ok for a while but just recently began doing it again.
Going to start troubleshooting this morning with a carve after each of the tests below:
- run dedicated circuit (drop cord #10AWG) & clean inside of controller
- Re-route USB cable
- Inspect brushes w/ spindle
- Mount temp sensor on my y axis motor(s) (Noticed this only stopped during carving Y direction)
- Relocate LED lighting away from controller
- Perform exorcism.
