In article , Ed Huntress
says...

Yeah, that's how it was used a half-century ago. Real top-quality
hand-scraping jobs, like on Moores, weren't finished with frosting.

The jig borers had hardened steel prismatic ways, ground to size.
They were seated in hand scraped female v-ways, scraped for
alignment. The ground surfaces were then lapped for alignment.
Because they were hard steel, they could not be scraped or
frosted.

The female v-ways that rode on the hardened prismatic ways
were hand scraped though. So even in this case the degree
of bearing was controlled, to be below a certain percentage.

I'm not sure if moore's book mentiones what that number
was that they considered optimal.

As a side note, a lot of the fancy photos of old machine
tools, which were covered with decorative engine turning or
frosting on the non-function surfaces were done as one-offs
for the catalog photos, I bet. Or, maybe there was a bit
of old-timey photoshopping going on! The cataract lathe
I have came with a nearly unused cross slide:

http://www.geocities.com/noramm10566/59slide3.jpg

Even though the ways and lead screws were pristine, and
showed zero wear, it still did not look much like what
hardinge said it should:

http://www.lathes.co.uk/cataract/img86.gif

A bit of a difference, eh?

Jim

Jim

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