Need Help!- step and dir pulse ?

[electric2u]

can someone tell me when i might need to use the step pulse and dir pulse in motor tuning? my cnc seams to run about .015 off even after doing the axis calibration. (can't find nothing loose)

thank you
kevin

[ger21]

Depends on the drives your using. Most work well with the pulse width set to 2, but some need it set much higher.

IF you need to set it higher than the drive manufacturer recommends, it could be do to a weak parallel port.

[electric2u]

so nothing to do with .015 off?

[Torsten]

Originally Posted by electric2u so nothing to do with .015 off?

You can change the steps per inch settings to come out closer.
The important question would be are you sure you are not just skipping some steps because you are asking more of your motor then it can deliver.
Make sure to run some tests at conservative acceleration settings with a slower then maximum feedrate to ensure your deviation is consistent.
Good Luck

[electric2u]

that is a good question, i might be doing that. thanks