Need help calculating steps per unit (rack and pinion)

[idtkid]

I have 1.8 degree steppers being run by 10 microstepping drives.
I have 24 tooth, 20 pitch, 1.2" diametrical pitch spur gear attached to the motor
This runs on a 20 pitch 14.5 degree pressure angle rack

Can someone calculate my steps per inch as I simply cant figure out the formula :x Thanks so much!

[H.O]

Hi,
If the diametral pitch of the spur gear is 1.2" then the "traveled" circumference is 1.2*Pi or 3.7699". So, 2000 steps = 3.7699" and 2000/3.7699 = 530.218 steps/inch.

EDIT: OR....when I think about it, diametral pitch might actually mean "traveled" distance per revolution of the gear and if that is the case then it's 2000 / 1.2 = 1666.667 steps/inch instead. Sorry for the confusion.

/Henrik.

[idtkid]

I did a steps per unit calibration with Mach 3 and my it suggested 533.33 so I think your first answer is correct. Thanks a ton for the help! Appreciate the fast response.