Cheap milling machine spindle - BT30-ER20, air powered draw bar + Tear Down!

[routercnc]

Thanks m_c. From what I can tell they should be more than powerful enough for what I need. I've seen them used on a 150kg bridgeport knee (usually via a pulley of 3:1 or similar) so my 40kg head should lift up, and also there should be plenty spare to push the quill/head down for drilling.

I was concerned about the fiddly wiring/soldering but I see they do sell a ready made breakout connector with the big plug on one end (around £10 I think) and labelled/crimped terminals on the other for all the ins and outs, and it comes with the motor and encoder connectors ready to plug in. I did look into Ethernet control as that would be very neat and some versions of the servo drive have that but then I would need to get into TCP, masks, addresses and so on. There did seem to be some ethernet adapters for the ESP32 microcontroller which might do something but I think in the end I've decided to stick with step/direction control which means going back to the big breakout connector.

I'm used to those 'special' manuals by now so hopefully with that, chat GPT and forums I can get it to do what I want. I do plan to read out the AB (and maybe Z) channels of the servo encoder from the drive into the ESP32 to get it synchronised with the main spindle encoder for rigid tapping, just for the challenge.