We have a working spindle!

The KBIC controller arrived from Axis Controls today, so I quickly wired it in to test it, and the spindle goes from nothing to full speed with little noise.
Stepper drivers have also been ordered, and will hopefully be here this week.

I now just need to work out all the extra bits I need (fuses, holders, regulators, mountings, wire...), so I can start getting everything wired up.