Machining the first motor module prototype

Recently I've written about the motor controllers, and now it's time for mechanical aspects of my project - the aluminum case holding the parts together. It took me about a week to finish a 3d model of the module. Then I 3d printed the parts, made some adjustments, and started milling the individual parts. The material used is PA6 aluminum (2017 T4511) bought in 70mm slices of different height. It is relatively cheap and easy accessible in my town (less than 8$ per kilo and ablut 1,5$ for band-saw cutting the slices). Milling in this material is very pleasant and at the same time mechanical properties of this aluminum alloy are sufficient for my purposes. While machining I did not have to use a lot of coolant (which is quite important as still use a plywood table). I mostly used IPA alcohol and WD-40 to cool down the part in moments where a lot of material was being removed. 

Now it is the photos time:

sun gear and bearing pressed onto the pin

I know the surface of the motor is sloppy it was done by hand, will fix it next time ;p

This part is the rotor extension so that I can press-fit a gear on it. The diameter step on the tip of the part is for bearing. It was milled from a 20mm PA6 aluminum cylinder.

Each 70mm cylinder slice was faced in order to get a flat reference point. Actually the one on the picture was earlier faced in the vice from other side, and this photo was made after facing from top side. 

I mostly used screws to fix the material to the table, as it was the fastest way considering I do not own any good claps yet. 

This is the lower part with PCB cap and stator press-fitted onto the cylinder. Now it is time for the distancing cylinder:

This was the part that required the most coolant as it is relatively thin and a lot of material has to be removed around it. I did not noticed any problems caused by overheating whatsoever. 

Probing the gearbox mount

slots made for internal gear's tabs 

though the endmill was a bit to big it looks nice and fits tightly!

lower planet carrier with additional sleeve for bearing ring

gearbox mount, top planet carrier, lower planet carrier ready to be assembled

And after milling the parts it was the time for assembling them: 

I'm really happy with the result, considering it was machined on a low cost DIY CNC machine. Of course it works - for now only in spring/damper mode (and open loop d/q voltages mode), but I'm working on a FDCAN communication app and more features right now. Hope you enjoyed it, and see you next time. 

I recently started documenting my projects on Instagram, so feel free to check it out: https://www.instagram.com/klonyyy/