Re: Cutting the Hex surfaces.

No tricks, no moving X axis, only the Z axis is moving to take
succesive passes. There are machines that do have the X axis goin
in and out during the rotation of the spindle, but that process is
used for turning pistons (as they are not round, but oval). I
forget what that is called - sorry, getting old.

In polygon turning, the flycutter (the Orange tool in the video) is
spinning just like a flycutter or even a face mill. The main
spindle is spinning the workpiece in the opposite rotation. As the
fly cutter passes by the spinning workpiece, it creates a very near
flat surface on the workpiece. The ratio of speed and number of
teeth control the number of flats. The ratio between the two
diameters (part and cutter) determines, to a certain degree, how
flat the surface will be.

Programming is incredibly easy...

M123 'M code to synchronize spindles
G97 S2000 M03 'main spindle
S1000 M04 'driven tool
G00 X1.0
G01 Z-.5
G00 X2.0

That's it, all the "Magic" is in the rotation of the two items (Part
and cutter) and their synchronization. The M123 is not the actual M-
Code nor is M04 for controlling the rotation of the live tooling,
but hopefully you get the idea.

Remember, this process goes back to screw machines and automatics -
prior to CNC. So, it all had to be done with: gearing, ratios, and
mechanics. As insane as it all seems, it is really very simple.

Chris