I am wondering if a PC that has CAM software could safely be connected to the net.

[JAZZCNC]

With a separate offline controller PC I don't see you'll have a problem, most current CAD/CAM software is written with the assumption that you have an active internet connection,

- Nick

That's what he's asking Nick. What affect would a ON line PC have if used for the controlling machine.!
This way he can change code on the fly at the machine if needed rather than going from Offline controller PC back to his ON line PC in house.