Hi, i have just finished building a 3 axis router running Mach3 and an now in the process of testing but could do with a little help. I am using Artcam as my cad/cam package. When i input a simple 2D program the whole program is displayed in Mach3 and executes to the end. When i input a bigger more complicated program involving 3D contours only part of the program is displayed and the machine starts to execute then grinds to a halt and Mach3 then hangs and i have to restart the program. does Mach3 have a limit to the number of lines in a program or does the problem lie elsewhere? Could it be there is something in the post output that Mach3 doesn't like? Any help greatly appreciated.