Which thickness CY cable do I need for 1.5kW spindle?

[JoeHarris]

Joe I generally use 4 core 1mm CY cable and earth the screen to a star point in the control box and I don't see the point of stripping such a lot of cable back 6" is more than enough. But I make these for the back of the motor

Thanks Clive, I thought he stripped a lot off! Do you 3D print those yourself?