[15mgtar]

Is there any disadvantages in accuracy etc on using a BIG nema 42 3200 oz compare to nema 34 1600 oz? or the disadvantage only the bigger one is more expensive?

[valmet58]

first go see that site
http://www.geckodrive.com/upload/Step_motor_basics.pdf

second:you have to be aware that the bigger is the motor the more
inductance it will have;that increased inductance will meen that you will have
to operate those motors at a higher voltage to get good performance;
third: the torque versus speed curve of big motors usually falls very fast.

[amplexus]

You may want to consider servo's if you need that much torque.
Amplexus

[ger21]

Depends on the application.