On Mon, 08 Dec 2008 17:19:07 -0500, Wes wrote:

I had to repair a machine today that uses a static reel to counter balance a slide
assembly that has a rotary encoder on a spring reel to measure displacement.

Looked like 1/8" cable over a 1.5" pulley that the cable wrapped 90 degrees. Just looked
wrong and the cable lasted 3 months. The cable is very lightly loaded, is there a ratio
of wire size and diameter to use in making the right sized pulley?

Thanks,

Wes


Hey Wes,

The sheave diameter should be a minimum 20 times the cable diameter,
which would be a 2-1/2" pulley. While the load has a major effect,
the bending radius is what causes most wear if there is no other
negative influence, such as improper groove size which is very
important too, or incorrect fleet angle(s).

Brian Lawson,
Bothwell, Ontario.