In article , Fdmorrison says...

"[S]ome machine builders still cling to the practice of handscraping the
ways--an admission that the machine work is not quite so accurate as it should
be. In these days of precision machine tools, it is indeed surprising to find
tool engineers who believe that a man with a scraper can produce a surface more
nearly flat than can be planed with a single-point tool on a modern planer [let
alone, grinding machine]."

And here Moore's smarts really show - his idea is not
to create a bearing surface with the scraper, but rather
to prepare and align a seat for the real bearing (the
hard steel prism, ground for dimension and surface
finish) and then bolted into the way whos (whoms? g)
alignment has been prepared by hand scraping. Sort
of the best of both.

In any event, moore felt that machine tool accuracy, and
that includes the planer mentioned above, depended ultimately
on hand scraped gages that were developed fundamentally from
master reference flats - hand scraped master reference flats.

This was not really a new concept, moore simply carried it
to extremes. But even in the mid 40s I suspect that it was
cheaper to hire an experience scraper mechanic to finsh, say,
lathe beds. Because the large machines to do them cost a
lot, and the men could be paid a fairly low wage in spite
of their skill.

Jim

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