X3 mill with rails, ATC, new motor

[Jonathan]

What sort of motor are you using for the spindle?
And how on earth does it achieve such a high power density?

It's the same type of motor as I used here - permanent magnet synchronous motor (PMSM), with an outer rotor. The high power density partly stems from the magnets, which replace the rotor magnetising current in, for example, an induction motor, resulting in lower losses. There is more to it than that though - e.g. differences in cooling.

This is how far I've got with rewinding the motor - two phases done, but I do have a low resistance from one phase to the stator, so I'll probably have to re-do that one and be more careful.



Cut out the motor mount for Z from 20mm thick aluminium yesterday:



This morning I cut the motor mounting plate for the spindle motor:



This is where it fits:



The large pulley (60T) isn't all the way on the spindle shaft, but this shows the general idea. The spindle pulley is keyed and the motor pulley fixed using four grubscrews, which should be sufficient...more on that later.



The spindle pulley is much bigger than the original gear, so I had to mill a bit off the top cover to clear the pulley and belt:



Z-ballnut mount (again):



I just need to make the Z-ballscrew bearing mounts, finish rewinding the motor and make the driver, decide if I need an encoder on the spindle and then I can continue with the ATC.