With the cheaper pulleys the top can bind between the sheave and sides of the
pulley. Binding rope will chew up the rope as well as add significant friction.
The better sailing-type pulleys that have been mentioned frequently have real
bearings (as opposed to just the sheave running on a pin) which will also
reduce friction. Larger diameter pulleys will also help. It's important to use
pulleys that are correct for the size of rope you're using.
I've been using the harken blocks, which are fancy pulleys. I have one that is
up some 90 feet or so with maybe 80-100 pounds of load, in near full sun, and
it's been ok for at least about three years now. They run maybe $15-20+ per
pulley but they are FAR superior to the hardware store stuff.
Using a "hard" rope will also help. Any rope that is squishy (like twisted
nylon) will deform on the pulley and tend to bind. You're better off with
braided rope. I use the Dacron stuff with the black outer covering that
everyone seems to stock, and lately I've been using some of the mastrant rope
which I think is a lot better but I haven't had any up long enough to say for
sure how well it holds up over time.
-Bill
Sent from my iPad
> On Sep 2, 2014, at 6:31 PM, "Richard (Rick) Karlquist"
> <richard@karlquist.com> wrote:
>
> Maybe someone can help me here. The problem
> I am having with pulleys is that they appear
> to add a significant amount of friction. I
> am not sure if it is in the bearing, or the
> pulley is too small in diameter, or maybe the
> rope diameter doesn't exactly match the
> half round surface of the pulley. I see that
> rock climbing pulleys are only 2 inches, like
> there is no need for anything larger. If I
> get one of these super duper pulleys, is my
> friction going to magically go away? Does the
> type of rope matter in this regard?
>
> Rick N6RK
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