Heat Treating 52100 Steel for the ToolMakers Flat - Part 1 

In which we start heat treatment on the first prototype of the ToolMakers Flat. 52100 steel is quite old, stable, and interesting. It's a chromium steel alloy, and is used in ball bearings and gage blocks. We, of course, are interested in the latter.
See the PFG.Live series for our live discussions about the ToolMakers Flat.
Of Clock Springs And Toolmakers Flats: ru-vid.com...
Info on the TIG rod that was used:
certilas.com/e...
www.americansp...
Many thanks to Robin Renzetti ‪@ROBRENZ‬ for his favorite groove dimensions and kibbitzing about lapping.
Thanks to Dale Bannister (IG: WidgetWorksMfg) ‪@TheWidgetWorks‬ for the gift of nickel-alloy TIG wire.
Thanks to Dr. Larrin Thomas ‪@KnifeSteelNerds‬ for the data in his book and web site and his continuing nerdosity.
Thanks to the NIST (formerly the NBS) ‪@NIST‬ for both data and motivation.
Thanks to my kiddo Jared for his excellent camera work.
Part 2 is here: • Heat Treating 52100 St...
References:
Knife Steel Nerds: "How to heat-treat 52100" knifesteelnerd...
NIST paper: nvlpubs.nist.g...
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