JRJohnson wrote:
Guys, I picked up a rusty piece of steel and needing to turn it down
I tried
cutting it in my band saw. Lo and behold, it would only cut about
3/16"
deep. I tried to cut a section off with my acetylene torch and it
wouldn't
even get red!!!! Finally had to grind it in two. It looks like a 1
5/8"
diameter rod with a half inch hole down the center. Further
examination
reveals that it is a piece of soft steel (1018?) surrounding a harder
(obviously) tube. Specs follow:
OD 1.630. Diameter of core piece 1.245. Diameter of hole is .535.
The
core is packed with with what looks like rusty swarf, or chips. But
they
are only mildly attracted to a magnet. The hard core piece machines
nicely
with carbide, and the chips are magnetic. The outer tube appears to
be mild
steel. On a polished end, there is apparently a very thin layer of
copper
or brass between the outer and inner pieces. But the most remarkable
thing
is that I held the flame of the cutting torch on the core piece for
at least
5 minutes without it getting hot enough to cut. Oh, color of the
grinding
sparks is almost the same as the sparks from the outer tube, IOW low
carbon
steel sparks.

For the life of me, I cannot figure out what the material is, what it
is
used for, or how it was made. Anyone have any ideas?

Thanks, James Johnson
Bewildered in Texas

Such properties would be handy for locking bars for a vault door, just
another wild-ass guess. Most I've seen have been plated, though. As
to how to make it, one way might be to stuff the various materials into
a larger, hollow billet for the outside, heat it up and roll them all
out together.


Stan
Stan