Well, I do have access to "country" machine shop that is reasonble, but I
think I can find a stock size close enough, maybe even be more suitable than
the original.

"Marty" wrote in message
...
Garland Gray wrote:
Thanks all.
I will be trying the GFN for one sheave anyway, but will get a delrin
alternate as well . Size may determine which ends up being used, as they
bracket the original sheave in diameter.

Garland, do you have a machinist friend, or maybe a hobbiest friend with a
lathe? Making a sheave from a chunk of Delrin is trivial, or aluminum, or
brass, stainless is a bit trickier, not to mention expensive.

Cheers
Martin (have lathe, will travel)

On Jan 31, 9:35*am, "Garland Gray" wrote:
I need to replace some old plastic sheaves, and I have the option of sheaves
made of Delrin, acetal, or glass filled nylon. (I have learned that delrin
is acetal, *but don't know if all acetal sheaves are delrin).
So what are the relative attributes of acetal and glass filled nylon
sheaves? I read somewhere that GFN might be more abrasive on the pin, but I
assume that it is stronger. Ronstan sells both, but their website doesn't
solicit questions.

Nylon is very susceptible to UV degradation, but low friction. Don't
use it unless the part is both shielded from sunlight, and gets a lot
of running wear. Acetal is somewhat harder, better at resisting UV,
slightly higher friction, costs more.

It seems likely to me that a drop-in replacement for a specific sheave
will only be available in the material that specific mfg'r choses.

Fresh Breezes- Doug King