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Limitations Of CNC Controlled Machines

Depending on their age and level of sophistication, CNC machines can be limited to the capability of their drive and control systems. A majority of CNC controllers don't understand circular arcs and straight line movements. A lot of machines restrict the arcs to principal planes XYZ. The rotary axis movement can be considered like linear movements, but with degrees instead of distance. For the creation of arcs or linear motions that are at an angle with the primary axes, two or more axes must interpolate together. Axes that are rotary and linear may also interpolate at the same time. If you have five-axis machines, all five must be perfectly synchronized which is not an easy job.