[TheForge] Ellipse-forging test result

[Bruce Freeman]

Well, I tried forging an ellipse at Marshall's open-forge meeting on
Monday evening.  I made a ring on the end of an oblong-cross-section
(~1/4" x ~1/2")  rod by scarfing the end of the rod and also the side of
the rod about 6" from the end, then welding them together.  Moderately
successfully.  I evened up the cross-section to rectangular. on a
treadle hammer (like using a flatter) and on the horn of the anvil. 
Then I rounded it up on the cone mandrel.  Next I flattened the sides of
the ring against the anvil and held it at about a 60-degree angle from
the horizontal and "ellipsed" it up on the cone mandrel.  I did have to
pull it off occasionally to flatten the plane of the ring, but this took
minimal effort.

The result was a success as far as the ellipse shape was concerned.  A
round cross-section would have been better to work with than this oblong
thing, but I was working with what I had and didn't bother rounding it
up first.

There was a limit how narrow an ellipse I could easily form.  The cone
in question was, I believe, from Centaur Forge, and stands about 12-14"
tall and 4-5" in diameter at the base.  I found I could not get much
narrower than 2:1 length:width, and that was pushing it.  It seems to me
that for narrow ellipses it might be better to use a round mandrel, but
I haven't tried using one.

As I expected, the elliptical ring is very eye-pleasing.  It's a more
pleasing shape than oblong - a flattened circle.  I think it is worth
the trouble.

I don't like the peculiar cross-section, but, as I said, I shoudl have
started with round stock.  After forming the ellipse with round stock,
that could be flattened to oblong or squared off, with minimal
correction needed to restore the elliptical shape, to produce an
elliptical ring with a non-round cross-section.  I haven't tried that
yet, though.

Bruce
NJ