I'm seeking some general advice for specifying finishes & tolerances for parts I wish to have made from the demon-spawn alloy known as Hadfield steel.
In case someone forgot, t's an Austenitic, work hardening, impact & abrasion resistant steel. Usually cast to near net shape, including the holes, because drilling the stuff is a nightmare. When a part calls for threaded holes, cores of an 'easily' machinable material (like 'Inconel' or 'Stellite') are inserted into the mould. You know the stuff with a machinability score of "0". The stuff they make rock crusher cones & jaws out of, and the teeth for earth-moving buckets and hard-rock scrapers.
I'm trying to get an idea of what is 'practical' to machine vs what is just copied down because that's what the bearing spec sheet says is expected.
There is a lot of anecdotal lore concerning this material. I cannot tell which of those stories are 'true, but obsolete', 'false, to scare competition', 'still applicable, when using 80 year-old techniques & setups', and 'contemporary fact still not to be ignored without consequences'.
Thanks in advance,
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