Can a fourth axis machine gears? Yes. A fourth axis rotary table on a cnc milling machine can be used to practically machine all types of gears. Your best bet is to go with a 4th axis that can interpolate, in other words, do simultaneous motion with the other axes on a cnc mill. Then you can do some really intricate designs on a piece of round stock. In this quick video, we decided to machine a miter gear. CNC Masters offers a 6″ 4th axis rotary table as an option to enhance the operations of their line of CNC mills.
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