Need Help!- Coupling stepper motor to ball screw

[ahab8783]

Hello all, I come again in my time of need.

I've recently came by some ball screws for my homebrew CNC mill but the output shafts on my stepper motors are much smaller than the ball screw shafts and the shafts on my stepper motors are geared. Does anybody know a coupling solution for mismatched shaft sizes? I know I could just drive the screws with belts, but I would prefer to couple my motors directly to the scerw shafts. Also, does anybody know a good way to remove the gears from my motor shafts?

[Fastest1]

Look up "Oldham Couplers". They are a 3 piece zero backlash coupler. you buy one half for the stepper the other half for the screw or whatever you are trying to join.

[Fastest1]

Coupling & Universal Accessories and other Couplings & Universal Joints at MSCDirect.com.
Also look up "lovejoy"

[doorknob]

It might be helpful if you could post some photographs of the stepper shaft with attached gears.

BTW, what are the shaft diameters that you are working with (for both the ballscrews and stepper motors)?

[siam]

Without more exact information on the sizes of your ball shaft ends and the stepper motors it's hard to give you good advise. In general, gear reduction heads on stepper motors are typicaly removable, however the gear on the motor shaft may be pressed on,...try pulling it off or cut it off using a dremal cut-off wheel if needed.

For the shaft coupler, you might want to look into "Flexible shaft couplers", you can find them on e-bay for only a few dollars each (shipped from china). They come in many standard shaft sizes and hold up very well for most stepper motor applications.

Cheers