How to make a pickup winding faceplate that runs 'true'

[John S]

What's this method called?

The technical term is "Ouch that bastard was hot" AKA shrink fit.

One problem with this is you don't get a second chance, if you do want a 'permanent ' job bore out to get a nice slip fit and then hold the faceplate on with a dab of Loctite retainer. Later if you need it off a bit of heat to the faceplate will break the Loctite.

To get it to run perfectly true make the faceplate slightly longer than the shaft.
Bore the 8mm hole in and put a small counterbore at the front, like your perspex one, now glue the faceplate on, allow to set and put the rear shaft of the stepper in the lathe, support the 8mm hole with a revolting centre and take a clean up pass across the faceplate.
Tape the motor wires to the body whist doing this.

This way it will be as square as you can get it.

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