> I'm in the process of refurbishing an old EZ-Way crank-up and
> looking to replace some lift cable sheaves which have excessive wear
> in the ID of the groves. The current 3" OD metal sheaves are sized
> for 3/16" cable. The sheaves are rather narrow, measuring 0.38" at
> the rim and 0.45" at the hub where the ball bearing is pressed in.
> The tower sheave brackets will only accept a maximum sheave width of
> 0.50", and that's tight.
>
> While looking at McMaster-Carr's web site (
> http://www.mcmaster.com/#wire-rope-sheaves/=o71onb ), I was
> surprised to see Nylon sheaves for wire rope applications. For the
> size I'm looking for, they have the same load rating as the metal
> sheaves shown near the top of the web catalog page.
>
> Does anyone have experience with using Nylon sheaves in the lift
> systems for crank-up towers? Somehow, this seems wimpy to me, but
> they do meet my max width requirements and have the same load
> ratings as similar sized metal sheaves.
I have a old EZ-way tower (RBX-50) and NO WAY would I
use any kind of plastic/nylon pulley on that lift system!!!
Sure, the nylon might carry the load when new, but nylon
eventually will get brittle in sunlight/WX and fail under
the load.
Just my 2-cents worth. :D)
73,
Charlie, N0TT
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