Need Help!- Mach 3 travel distance

[Bell 430]

Hello folks,
I'm very new to this, I've searched the forum,but didn't find an answer.
I have Mach 3(liscensed version) installed, running a Shopmaster eldorado bridge mill, with ball screws, so heres my problem
When I do the calibration, I can get the machine to move 1 inch in the proper direction, and back, minus .002(Not bad for not using backlash yet)
BUT if I tell the machine to move 3 inches(g0 X3) the machine will only move 1 3/4 inch. the native units are set on "Inch", so I'm perplexed!
Help
Thanks

[Crevice Reamer]

Hi Bell. Welcome to the Zone!

Due to mechanical differences, sometimes you have to tweak the steps per inch up or down to get accurate movement. Mach3 can do this for you.

http://www.cnczone.com/forums/showthread.php?t=78713.#3

CR.

[SORCHEROR]

you said the 1 inch move was off only .002?and the 3 inch move is 1.25 off,sound like your loosing steps,try moving the x 3 inchs and slow feed,not rapid,maybe you need to better
tune the motors or your axis is binding at the 1.75 point

[Crevice Reamer]

Good point. Also check the set screw tightness on your couplings/pulleys.

CR.

[Bell 430]

thanks I found it
I uninstalled then reinstalled Mach 3, everything is working great!!

thank you for the help