[smallcraft]

Just starting tuning a new CRP 48x96 pro machine. I'm using Masso as the controller. As such, I cant use the CRP xml file for Mach 3. Masso needs to know is the amount of linear travel per motor rev. I'm using the NEMA 23 with 3/8" shaft. From the information I have, I think I'm looking at 1.1519 inches travel on x and y per rev. Can anyone familiar with the CRP R&P drive setup confirm? Thanks much!

[ger21]

The info is on their website.
3.14159 per rev.

PRO Rack and Pinion Drive, NEMA 23 | CNCRouterParts

[smallcraft]

I saw that. However, there is a 3:1 (or 2.73:1) reduction. So it's not 3.1459 but 3.1459 divided by 3 or 2.73. That's what's not clear.

From the website:
The R&P system is based on a pinion with a 1" pitch circle. The total linear distance traveled per revolution of the pinion is thus 3.14159". With the 3:1 reduction, this means that the distance traveled per motor revolution is 3.14159 / 3, or 1.0472". If you have a stepper with 200 steps per revolution, this means you have 200 / 1.0472" = 190.9861 steps per inch, or 0.005236" per step. With 10x microstepping, you would have 1909.861 steps per inch, or 0.0005236" per step. For the optional 3/8" pulley, this number changes to 1736.237, as the motor pulley is slightly larger.

[ger21]

Yes, I should have read the next line.

this means that the distance traveled per motor revolution is 3.14159 / 3, or 1.0472"

They should be a little more clear, as you would have 3.14159/(60/22), or 3.14159/3.727272 = 1.1519173063162575207696359072025

[smallcraft]

Thanks Ger21, I think that's it. Seems to work great.
Dan