I also notice that you have selected a leadscrew with an efficiency of 30%.
Have you not considered a ball screw? A ball screw will be far more efficient and also will not wear as quick.
As an indication of the efficiency, a ball screw can be between 80-90% efficient, so for the same motor you will get a lot more thrust with a ball screw.
Allot of people buy a three or four axis driver board then the motors and find that the drivers just dont cut it on larger motors,
and in some cases they just start to smoke.
Look at the torque curves of the sy60 motor and you will see two torque curves at two different voltages.
This shows how important voltage is.