Cnc steps per setup in mach 3 help

[JAZZCNC]

Ok well first make sure Mach3 units are set to Millimeters. If not then change and restart mach3.

Some explination may help first.! . . Your motors move in 1.8 degree steps so 360deg / 1.8=200 full steps per rev.
This is a very course step amount so your stepper drives will allow each step to be broken down into Micros steps. It's this Micro step amount you require to calculate the Steps Per setting along with the pitch or lead of the screw.

For the steps per it's a simple calculation. Divide the micro steps setting your drives are using by the pitch of your lead screw. ie 800ms / 3 = 266.666 steps per MM.

Now regards the micro stepping amount then you don't want to go too high other wise you will stress the system needlessly. People often believe setting the micro stepping high increases there resolution but it doesn't. All it does in most cases is stress the system causes lost steps and slows the machine.

The main advantage to micro stepping is it gives smoother motor operation but it does come at a cost in the form of pulses required. Depending on the motion control device or pulse provider ie: parallel port etc then you only have a certain amount of pulses available. Which if using the parallel port this isn't an awful lot and a high MS setting will drasticly slow the machine down and stress the parallel port. Which 99% of time leads to lost steps and stalled motors.

Like wise you don't want to go too low other wsie your motors will have a very rough action to them.
Your motors use 200 steps for one revolution. This would be known as FULL stepping. But if you run at this setting on your drives(if they will allow it at all) the action will be quite course and can lead to issues with resonance affecting motor/drive performance. So rarely is Full step used. Often stepper drives will only start at 400ms.!
Now for a machine using a 3mm lead screw and running with the parallel port then 400 or 800 is good amount as it won't stress the system and give decent amount of speed. Going higher will slow the machine and potentially stress the system. Never go above 3200 as theres very little gain and your just wasting pulses.