Re: [CAD_CAM_EDM_DRO] Re: True 4th Axis milling

> about the #2 method in Vector
> could that cut say a 'J' shaped cam grove onto a cylinder using
> a cutter with a diameter smaller than the grove width and still keep the
> sidewalls of the grove parallel?

Brian,

If I understand correctly, the problem was that the tool offset was
accomplished in the rotary axis, so the wall on one side was based on
one radial and the one on the other side was based on a different
radial, hence they are not parallel, but rather interesect at the
center of the radial axis. Sounds like what is needed is to
accomplish the offset using the linear axis instead.

Looking at it a different way, you would need to generate small
motions in X and Y to move the smaller cutter around inside the
outline the larger cutter would occupy, so that the circumference of
the little cutter is tangent to the circumference of the imaginary big
cutter at the point where cutting is occuring.

One way to accomplish this would be to write a post processor that reads
the motion commanded for the rotary axis and unwraps it to a flat
surface, calculates appropriate offsets, but applies them to the
linear axis instead.

This is the kind of situation where writing your own specialized
toolpath generator is worthile - the programmers who took on the much
harder task of writing a general purpose generator didn't envision
what you might want to do, and didn't allow for it.

Chris


--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
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