My ball screw kit came with 6.5x10mm motor coupling and I need 8x10mm. So I could drill out the ones I have. But I question how good these are to begin with. They are an aluminum alloy slit type with small 2.5mm screws to apply the clamping force. Wouldn't a slit type with set screws be better than the clamping type, less likely to slip? My steppers have a notch in the shaft for a set screw but the ball screws do not. If so do I grind a small notch in the ball screw shaft?
Yes grind a small flat for the setscrew, I would just buy the right size, If you have a metal lathe you can drill them out well enough but any other way will be disappointing, they are cheap on ebay any size you need. Use loctite. Cheers Gary
On the ball screw, slide the coupling on the shaft. Use a transfer punch through the set screw hole and punch the shaft . Then take the coupling off and drill a dimple for the set screw to fit in .this is just another way instead of grinding the ball screw shaft.
You can put it on the coupler to rod interface as well.. just be careful if using red it will be difficult to get back apart if you need to..