Quote Originally Posted by luke11cnc View Post
step/mm is 85.46301769
That's very interesting...I just don't see how with 30T pulley on motor and 15T pulley on the 10mm pitch screw it could be anything other than 80 step/mm. Unless the pulleys got mixed up somehow. Sounds silly but could you count the teeth on the Y-motor pulley. I reckon bearingstation accidently sent me 28T pulleys and neither of us noticed as that gets 85.71429 step/mm which is very close. If that's the case you should check Z and put the 85.714 in for Z.

Jazz did you arrive at that number by scaling and measuring, or some calculation?