Above is an example of what the cut files look like. The blue lines are the outside shape cut the red lines are inside cut lines

CNC Cutting.....

What is a CNC router?
CNC stands for Computer Numerically Controlled. CNC routers are incredibly accurate and can be programmed to automatically drill, cut or carve materials and increase productivity. Most likely the machine shop that cuts your parts will use a plasma CNC cutter

CNC Plasma Cutter

Plasma cutting is a process that cuts through electrically conductive materials by means of an accelerated jet of hot plasma. Typical materials cut by this process include steel, aluminum, brass and copper though other conductive metals may be cut as well. Plasma cutting is often used in fabrication and welding shops, automotive repair and restoration, industrial construction, salvage and scrapping operations. Due to the high speed, precision cuts, combined with low cost of operation, plasma cutting sees a widespread usage from large scale industrial CNC applications down to small hobbyist shops.

2 Dimensional / 2-Axis Plasma Cutting[edit]
This is the most common and conventional form of CNC Plasma Cutting. Producing flat profiles, where the cut edges are at 90 Degrees to the material surface. High powered CNC plasma cutting beds are configured in this way, able to cut profiles from metal plate up to 150mm thick.[1]

CNC Plasma cutting is used to cut shapes and contours through the full thickness of flat sheet or plate metal and through the wall thickness of sections such as pipes and structural beams. It is this output of a 2 dimensional profile or a profiled section that has earned Plasma Cutting it’s general categorization as a “Profiling” process.

Here is a link to the full article.....