Are taper lock pulleys a good choice for ball screws?

[routercnc]

The other thing to think about is for an axis with double ballscrews you need to be able to square the gantry. This might mean being able to rotate one ballscrew very slightly by hand (without the pulley secured) until the gantry is square, so a key way or D flat would not work as this puts the pulley at a fixed location on the ballscrew. A simple pair of grub screws allows the pulley to sit at any angle on the ballscrew.

Also on the inertia side I did the calculations for machine design years ago and the mass of the gantry was a pretty small part of the motor requirements. The acceleration of the ballscrew was a large part of the motor requirement, and this in turn related to the ballscrew inertia. Inertia relates to having mass a long way from the axis of rotation, so heavy pulleys will have an effect. If you want to pocket them out then removing mass furthest out makes the biggest difference. And larger pulleys are significantly worse as inertia relates to the square of the radius so goes up quickly.