Quote Originally Posted by paulus.v View Post
The 48V PSU will make a difference. Try with 4.5A but check the motors temperature, if they'll get too warm or hot, reduce the current. Higher current increases only the low speed torque.

Hiwin rails need to be very carefully aligned to have a smooth movement.

https://www.youtube.com/watch?v=AGT5gXpcmBA#t=1m58s
that video is good info, learnt a lot about hirwi rails, best way line 1 side and slide car to each bolt both sides as you tighten rail up, moves super smooth then, as there is drag on them before fitting as they are preloaded, kev