I use ArtCam JewelSmith 2008, with a 3 axis mill.  I save all my toolpaths to an .mmg file.  Once I switched to Mach3 with a new 4 axis mill, my Z is going crazy.  My CAD software will save my work to about a hundred different G-code files so what is the best one to use with Mach3?  My mill is a Taig with Gecko stepper motors.  any help is appreciated.  Chuck

I know nothing about ArtCam, but you should be using a pp configured for Mach so you get the correct gcode posted.
RICH

thanks for the reply rich.  what is a 'pp'?

the version of Artcam I have offers Mach2mm.cnc, but that also caused my Z to nosedive through my wax.

Seems like that post processor from the file description may be for Mach version 2? ( which is very old ) and is for metric units.

RICH

it is.  my CAD software is 2008 and only supports Mach 2.  Any suggestions?

Try this post 3 axis artcam, creates a .txt file

I am unable to open the MyRouter-3axis3.zip file that you attached.  My laptop does not have the required program to read it.