Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: psjflyer on March 03, 2009, 09:11:19 AM

Hello everyone, I have been building a JGRO design router. I have installed the Hobbycnc pro board, with the 305 oz Motors. I went with the acme 1/2" 10 5 start lead screws on all 3 axis. I am getting ready to do some tuning and testing in the coming days. I have looked high and low and tried to understand this tuning thing, but I have come to realize that I need HELP ???. I have follwed the manual on calculating the leadscrew distance and tried to understand it. I am trying to understand the revs per unit for my setup.
I am looking for the steps it will take for my setup.
lead screw 1/2" 10 5 start 1/10=0.1 x 5 = 0.5 this is my effective screw pitch right ???
305 oz motors 200 steps per rev I will be 1/2 microstepping This is where I get lost. PLEASE HELP...............
Thanks
Gerald

OK I think I found it. Please let me know if this is it.
2000 steps per rev for the motors. 1/2" 10 5 start 2 rev per unit. that means that I need 4000 revs per unit Right.
If I microstep it 1/2 that means that 4000 x 2 = 8000 steps per rev for the motor.
WOW that number seems low compared to some of the other numbers that I have seen I found one on here that had 25,000 for one rev. I think her was 1/8 microstepping. Please let me know If I have this or not.

If your pitch is .5 it will will be 200 (motor steps per rev.) x 2 (1/2 = .5 stepping so 1/.5 = 2) x 2 (screw pitch is .5 so 1/.5 = 2). That will give you 800 steps per rev.
Brett

Brett, I want to thank you for your q

Brett, I want to thank you for your quick reply. Then I will have 800 steps per rev and not 4000? Why is it then I see numbers in the 25,000 range? I know it has all to do with the tread pitch, but I did not think it would be that big of a difference. Brett, So I would change the 2000 rev per unit in the motor tuning section in the lower left coner to 800 rev per unit. Just trying to make it as understandable as possible.

No problem.
So I would change the 2000 rev per unit in the motor tuning section in the lower left coner to 800 rev per unit.
Yup, if the numbers you gave are correct, you should have this step sorted. :)
Brett