On Sep 25, 1:00*pm, Leon Fisk wrote:
On Wed, 24 Sep 2008 16:50:27 -0500, "Robert Swinney"

Drop a 1" diameter ball bearing from a height of 10". *It should rebound back up to 9" if the anvil
surface is properly heat-treated. *I'm not sure I believe this. *Can someone confirm?

I've heard of building your own hardness tester using this
method.

You need some known items of hardness for calibration
though. Find some glass tubing maybe 10-20 inches long that
you can make marks on and your steel ball will easily slip
into. Using a known surface drop the ball (from the same
height) and note (mark) how high it bounces up. Repeat
several times and take the average. Repeat process on
another known item. Test your unknown item and note how high
the ball bounces.

--
Leon Fisk

My scleroscope rebounds to 4 of 10 off my anvil, which definitely has
a plate welded on the top. A carpenter's hammer reads the same, a HSS
bit held in the milling vise reads 6. The anvil can be filed with some
difficulty. It's fine for hobby work.

It's quite difficult to get the same reading repeatedly off small
samples even when they are clamped in a vise, and this is a
professional instrument, although an old one in suspicious condition.

I would hold the glass tube upright with a level to minimize friction
and record the rebound against a ruler with a digital camera video.

Jim Wilkins