[PropellerHat]

Hi

I am designing a poor man's ATC on a my first mill that's also yet on the drawing board. After some hours of trying to understand the sensorless vector control of the MM4 I have to admit I did not get answer to this:

Is it possible to command the spindle (Teknomotor 1,6Kw in my case) to hold still? If so, what kind of a holding torque is available? I plan to unscrew the ER20 nut with just the spindle holding the shaft, if it's possible.

How about the very low rpm torque? In range of some tens of rotations per second (20 maybe) is there any usable torque?

I have the VFD and spindle waiting for the frame to be cast and everything to be bolted up, so can't do any testing yet. (Also I still haven't bought the operator panel, still poundering if the AOP is necessary or not)


Thanks!

[mactec54]

Hi

I am designing a poor man's ATC on a my first mill that's also yet on the drawing board. After some hours of trying to understand the sensorless vector control of the MM4 I have to admit I did not get answer to this:

Is it possible to command the spindle (Teknomotor 1,6Kw in my case) to hold still? If so, what kind of a holding torque is available? I plan to unscrew the ER20 nut with just the spindle holding the shaft, if it's possible.

How about the very low rpm torque? In range of some tens of rotations per second (20 maybe) is there any usable torque?

I have the VFD and spindle waiting for the frame to be cast and everything to be bolted up, so can't do any testing yet. (Also I still haven't bought the operator panel, still poundering if the AOP is necessary or not)


Thanks!

No these spindle motors would not be able to hold enough torque, to undo and tighten up the collet nut, the correct torque for a ER20 Collet Nut for collets 1/16 and above is 59 ft / lbs., you will need a locking device to hold the spindle

[PropellerHat]

Ok. Thanks for the info. Plan B.