CNC Mill Upgrade


#1

I am looking to upgrade the X & Y axis on a CNC mill i have bought. The mill is a small Denford Starmill currently running 30V and 2A nema 23 steppers. I was planning to upgrade to Turnigy L3040 480KV with a 1:6 reduction belt drive. I plan to run on 12V with AEDB-9140-A14 encoder. This ought to achieve 4800mm/min or 189ipm movement. I will still have a requirement to run around 200mm/min im wondering if there would be sufficient torque. Can anyone clarify?


#2

I can’t comment in detail but wouldn’t you need to define “sufficient torque” for someone to provide advice? Or have I missed where that info is provided?


#3

Sorry i missed the info. The current steppers output 0.5Nm at their very maximum.


#4

The torque is given by 8.269933431 * I / kv where I is the motor current and kv is the KV value of the motor in rpm/v. So the motor you specified at it’s max current would do 0.9 Nm. But to expect to hold a torque continuously you have to derate them very significantly, or else they will overheat, unless you have very good cooling. Though with a 6:1 reduction, I believe you should be able to get 0.7Nm after reduction pretty much continously, as that is de-rated by factor 8, which is quite a lot.