You may spend more time with the software than your CNC mill, so it's worth spending a few dollars if the paid software makes CNC machining easier. We'll cover a few paid products in addition to free options. CNC control software (Makes your machine follow the g code tool path).CAM Software (Lets you turn the drawing into a tool path in g code format).
Starting from your design to the g code for your CNC machine, you're going to need several CNC software applications:
