[X2cnc]

When I built the power drawbar for my X2 I removed all of the electrical boxes from the head and column. I have them sitting on the bench next to the machine.

Since the wiring appeared to be soldered at both the motor and the box, I cut the wires and their protective housing. Now I need to splice in about three feet of extension wire.

The protective housing was flexible plastic over flexible metal. I assumed the metal was for RF shielding for the DC motor, so I've been looking for some kind of metallic braid to put over the extension wires. Then I began to wonder; there's no apparent shielding in the plastic controller box, and I would expect the Xylotex box and steppers would be pretty noisy on their own.

So, is the metal covering on the DC motor wires for RF, or is it simply mechanical protection for the wires?

[Al_The_Man]

That sounds like you are describing Liquid Seal Flexible Conduit, if so this offers both mechanical and electrical EMI protection, it is also important that the conductors to the motor be twisted together.
Al.

[X2cnc]

No, the three wires are just pulled straight through, not twisted.

[Al_The_Man]

A DC motor would be two motor wires and a ground?
Ideally the DC should be twisted and the ground separate to the two.
Al.

[The Blight]

I run my motor without any kind of shielding. It just there for mechanical shielding. RF shielding a brushed DC motor wire is kind of a waste as far as I can see. The shielded conduit is not connected to ground either, so it's kind of useless. And nope, this is not twisted cable. If you want any kind of shielding, just shield the motor controller from the drivers, and use shielded cables for the signals.

[Al_The_Man]

When DC carrying conductors are twisted together, the magnetic radiation, (not necessarily RF), is mutually cancelled out.
It usually does not take much to do this, and this is a recommendation of many Servo motor manuf.
It would also pay if the flex. conduit was grounded.
Al.