So are you going to use one motor for the X and two ball screws?
This can work well, but you need to take note that if the belt is quite long it can get a bit springy and you will see a bit of hysteresis.
I would personally use two motors and drivers.
A belt system can mean a loss of 10%.

Quote Originally Posted by AdCNC View Post
taking into consideration that the belt coupling could be 1:1 effectively each ballsecrew would see 1415 oz-in of torque thats not taking into consideration drive losses! thats if i used a monster 2830 oz-in stepper!