On Thu, 21 Jan 2010 16:02:04 -0800, "T.Alan Kraus"
wrote:

wrote:
On Jan 19, 5:09 pm, 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 can remember drawing an "ellipsoid" using a compass back in grade
school, was part of some kind of drafting thing, Was drawn as 4
separate arcs, I remember that Left some sharp points at the ends of
the major and minor axes, which could be dubbed off afterwards if you
were actually cutting stuff. Don't remember much more than that.
Maybe an old drafting text would have the procedure.

Or you could build an actual ellipse generator, I've seen some for
cutting photo matts, too. Isn't much more than a pair of cross slots
with sliders and a bar linking the two. As the bar goes around the
end traces out an ellipse that depends on how closely the two sliders
are linked for major and minor axis ratios I suppose it could be
hooked to some sort of pantograph linkage to get smaller ellipses.

Stan
There is a device for a BP mill called a Volstro quill adaptor that will
allow you to mill an elipse.

Indeed. Leigh at MarMachine has two of them for sale IRRC. $1200 and
humm..$2000 for the bigger one.

Gunner

The current Democratic party has lost its ideological basis for
existence.
- It is NOT fiscally responsible.
- It is NOT ethically honorable.
- It has started wars based on lies.
- It does not support the well-being of americans - only billionaires.
- It has suppresed constitutional guaranteed liberties.
- It has foisted a liar as president upon America.
- It has violated US national sovereignty in trade treaties.
- It has refused to enforce the national borders.

....It no longer has valid reasons to exist.
Lorad474