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Pete C. Pete C. is offline
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Default Using a rotary table to cut an approximate ellipse?


Ignoramus8727 wrote:

I would use the "Egyptian CNC" method, it is probably the easiest.

It took me less than 1/2 hour to cut a circle just turning dials
according to instructions from my perl script.

http://igor.chudov.com/projects/My-B...ian-Style-CNC/


Does your method leave stair steps in the result? I can't imagine being
able to manually move two axes in small enough steps for a smooth result
without going bonkers. With a rotary table, the four arc will be
entirely stepless.



i

On 2010-01-20, Pete C. wrote:

axolotl wrote:

Years ago, Errol Groff posted some pictures of some packaging prototypes
he had made. The bottle top was shaped in an ellipse. Can anyone give
the procedure for fabricating an elliptically shaped object using a
rotary table, given a rectangle size that contains the ellipse?

Kevin Gallimore


I expect you probably have to break it down into 4? separate arcs and
cut each one in a separate setup with the part and mill positioned the
proper distance from the center of the rotary table.