Talk about glam jobs � About once a month, we�d go over to the slaughter yard to get cows� teeth for Dr. Mueller. Then we�d fixture them on their side and run them in a machine that scrubbed them with a brush for weeks. The cool thing about cows teeth is they are comprised of roughly concentric hard and soft cylinders of dental running from top to bottom. � For cows, it made a sharp cutting surface for chomping grass off at the stem. � For us, we could count the number of layers to evaluate the wear characteristics of different tooth pastes.
Beavers� teeth have hard front dental and the back is soft, so they�re no good for wear experiments, beyond the issue of the difficulty of getting beaver teeth. Not coincidentally, the venerable P-38 US GI can opener was designed on the same principle to be self sharpening.
OK, enough teeth stores. Years ago, Norm Einarson ran an experiment to determine insertions from a gold plated board into a connector. Boards were all the same thickness (0.062") and had 100 uinches base nickel. Results were: � 100 uinches gold = 500 insertions � 50 uinches gold = 300 insertions � 30 uinches gold 50 to 75 insertions � 20 uinches gold 10 insertions.
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