compund curves...
You may want to build a robotic arm type cnc instead of a gantry setup... I think this would allow you to hit the 4th axis that your looking for.
This is a tuffy and out of my league for awhile.. I am going to start some robotics myself with a bunch of spare motors etc I have and some spare aluminum..
I think I can repeat a "arm" with some rotational control on the "wrist" with the hand being a router..
Input anyone???
Coog
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