Hi folks.... I'm Sonny and I'm new here.  Ive been using CNC's for about 15 years now but this is my first go around with Mach3.  The way I operate isn't as sophisticated as most of you are so I'm hoping the solution to my problem is an easy one for you.
All of my machining is done by first designing in a 3d CAD program (I use ArtCam13), which I do in all MM, then generate a toolpath in MM, open it in Mach3, set my Zero and machine.  I don't write my own code, etc... so I'm more lost than most when there is a problem. 

Now for my problem....  I cannot get Mach3 to read/feed in MM.  No matter what I do, it's travelling in INCHES, even when MM is chosen everywhere I know (or have found) throughout Mach.  I have set the units to MM, under settings I have made sure MM is chosen , etc...   I have also re-ran the toolpath many times to make sure it's generating in MM.  Mach even jogs in INCHES even though I have MM chosen.  I have rebooted the program many times and checked that MM is the chosen units. 

I'm sure there is a simple solution and maybe even so basic it's kind of funny.....  Any help would be appreciated.  THANKS!!!

Look at the gcodes you are using. Do they have a G20 or G21? G20 is imperial, G21 MM.

http://en.wikipedia.org/wiki/G-code

G21 is the code its running.  I try to attach a pic here.  Also, its jogging in inches as well which isn't associated with code (or is it...??).  Thanks for any and all advice. 

I would think that until the code is loaded the machine should run in whatever set up units Mach is configured with. After that it should be in the code. Hopefully someone with more experience will chime in.
Just out of curiosity, what version if Mach are you running?

Make sure you select mm for your Native Units, then select "Lock DRO's to Set-up units" in Gen Config (top left).
Then the DRO's should show metric values weather running g20 or g21 files.

Russ

im running version R3.042.038.   I believe it says Version 2.0 at startup
I have seleceted MM in the native units and it remains selected when I reboot or restart the program. 
I didn't know about the lock DRO to Setup units.  I'll give that a try as well. 
Thanks guys

Make sure your steps per unit are correct for your Native UNits being mm's.
If you do a G0 X1 and then a G0 X0 in MDI, how far does it move?

Thanks.  Just ran the exercise and it moves 1 inch each way.  Mm are chosen in the native units.  Any thoughts...?

Your steps/unit are set wrong in motor tuning. You need to change them so the machine moves 1mm when you tell it to.

Thanks for taking the time to help.  I'm not sure what to change it to.  Right now the motor tuning screen reads velocity per mm at 100.  The steps per are 10160.  Everything else on that screen appears to be associated with mm.