On 26-Nov-17 7:15 PM, Ed Huntress wrote:
....

It isn't clear what you're referring to here, but gray cast iron does
stress-relieve over time. Pratt& Whitney Machine Tool used to leave
their castings out in the yard for six months before machining them.
That was common practice before people figured out the cost of "work
in process" (WIP).
....

Back 50 year ago now, nearly, bought a Powermatic Model 66 TS and
arranged for direct pickup from factory in McMinnville, TN. Talked them
into tour while there; they had mounds of raw castings pile all over the
yard 20-ft high; they used 18-months for jointer tables and the like; a
year for the TS tables.

Now, it's an abandoned lot...

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