KLC Lewis wrote:
"Garland Gray" wrote in message
...
Perhaps I didn't state that clearly. I place a high value on serious
replies here. I wasn't complaining over just one response, or the quality
of it.

I'm not asking others to make my decision for me; but why try to reinvent
the wheel ? The idea of newsgroups is to share experience, I assume.



From Brion Toss's book

Loads on the sheave itself are not so concentrated as those on the
bearing, but sheave material can be important relative to cost, weight,
and stability under load. Nylon, for instance, is very cheap and light
but can distort under heavy load. Worse, it swells when wet, increasing
sidewall friction. Delrin sheaves are more stable and nearly as cheap,
making a good medium duty sheave. Bronze, stainless, and aluminum
sheaves are heavy and expensive, but will stand up to extremes.

On sheave shape

Sheave score profile,
Semicircular for three strand and common braid.
Flat bottomed for kevlar
V grooved or semicircular with a notch for wire and rope

Gordon