In article , Gerald Miller
wrote:
Grant Erwin wrote:
So let me get this straight. The line shaft is running, the drill
spindle is turning, you throw the feed into neutral, and then what?
put a hook on the belt and just hork it over? I believe you, but I
can't imagine how you'd actually shift a flat belt while it's
running. I have a flat belt running my lathe and it's pretty tight,
and if I monkey around with it much it will catch something and throw
it.

Back in the 1950's I used to work in a place that employed man, who claimed
to be a "millwright", i.e., a generally skilled mechanic, who had his shop
near to my laboratory. The lineshaft in that shop drove several machines via
a flat belt for each machine. These belts ran on a pair of pulleys, one
fixed to the line shaft and the other free to run on he shafting. They were
called "fast and loose" pulleys.
A long lever carrying a fork was mounted so that to start work on a machine,
the chap shifted the belt over, never actually having to handle the belt
himself. Both pulleys were crowned, so that once the belt was shoved over,
it ran on that pulley and did not try to go back. As another contributor
wrote, the belt was slack enough to slip if overloaded, but then it could
run off the pulley and the lineshaft had to be stopped to replace it. The
belts were doctored with the chap's private belt dope, probably a rosin
mixture, to increase their friction. Guards wre not thought necessary in
those days!

All memory work and probably a bit wrong here and there.

I remember listening to the chap telling me tales of years ago instead of
working. Good times, those!

G.H.Ireland (retired industrial chemist)

--
igor
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Acorn RISC OS4
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