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measuring thermal expansion

updated tue 17 oct 00


michael wendt on mon 16 oct 00

In the early 80s, I built a device that can be used to measure =
thermal expansion. It consists of a Tasco rifle scope mounted on a =
framework that pivots with a contact point 1" from the pivot. The bar to =
be sampled is chilled in ice water until no temperature change is noted =
and then placed in the holder clamp quickly beneath the contact point =
and a reading is marked on the target. An hour later, the bar is at room =
temperature and a second mark is made on the target. I was able to =
double the distance to target with a mirror on the back wall of my =
studio some 70 feet away. This gives me an amplification of movement of =
1665:1 so that a 5" bar of my clay moves the cross hair on the scope =
1.25" over 22 degrees Celsius. Anyone with a drill press and a welder =
can build one for a few dollars. You could use a laser pointer instead =
of the scope if you want.
It is NOT a scientific instrument, but it can help by showing =
whether you are headed in the direction you want.
Regards, Michael Wendt=20