[Kutton]

My first machine was belt driven and mach3 would calibrate. I changed to ball screws and i have been unable to calibrate. Any suggestions?

[CitizenOfDreams]

By "calibration" do you mean finding the correct steps-per-unit values?

[Kutton]

Yes

[CitizenOfDreams]

Those are pretty easy to calculate without using Mach3's wizard. Post some information about your machine:
- ball screw thread pitch
- ball screw number of starts
- stepper motor degrees per step
- stepper driver number of microsteps per step
- any gearing between the stepper motor and the ball screw.

[Kutton]

SFU1605 RM1605 1605 Ball Screw
Pitch is 5
Start is 5
Nema 23 57mm Stepper Motor High Torque
200 steps

[CitizenOfDreams]

You did not say what your microstepping is, but let's assume it's 8.
Then your steps-per-millimeter would be:
200*8/5=320.
If you are using inches, multiply 320 by 25.4.

P. S.
According to the Internet, SFU1605 is single-start, not 5-start. So it has 5mm thread pitch and 5mm lead.

[Kutton]

16

[CitizenOfDreams]

Then 200*16/5=640 steps per mm.

[Kutton]

Thank you for your help. When i am twicking movement when movement is more than requested do i add or substrat ?

[Kutton]

Thank you.

[CitizenOfDreams]

If your ball screw is accurate (and it probably is), then the calibration should be spot on. But if you do need to tweak it, then BIGGER steps-per-unit means BIGGER movement.

edited. sorry, got it wrong the first time.