Re: Toothed belts for DROs

Hi Lew,
I have a watchmaker's lathe from my 'prior life' as a watch
maker back in the 50's and ran into the same problem as you.
Back then, we used a plastic belting which was heat fused and
I was never happy with. Anything less than a perfect joint and
you got a bump and a broken belt all too often. Tried O-rings;
OK only if you find one that will fit. They use CA (super glue)
for making O-rings from bulk stock, and it works OK when they
are used as a seal; that is when retained in a proper seal groove.
But the joint won't hold up in tension when used as a belt.
Then my wife dragged me into a 'rock shop' (those folks that polish
rocks, HER hobby) and the guy had replacement belts for his rock
tumblers. One was perfect. It is a sorta yellow translucent
material. He had sizes that sound like what you are looking for.
Don't know how to locate a source, but a web search might turn
up something. Been a long time, but the belt is still good as new.
They ARE available, don't know what the material is, but
it's better than a Viton or Buna-N O-ring IMO.
Al

--- In CAD_CAM_EDM_DRO@y..., "lew best" <bcl@c...> wrote:
> Hi Alan and Art
>
> Interesting this should come up; I recently bought a small coin
sorter for
> use in our Laundromat business that uses such a belt. In this case
it
> wouldn't have to be a toothed timing belt as the pulleys are not
toothed but
> the VERY ragged belt on it now does have teeth.
>
> I need a replacement and had thought of using a giant O-ring if I
could find
> one or get one made. The belt would be about the size that would
surround a
> CD; if an O-ring would need to be made of about one quarter inch
diameter
> material.
>
> How does one splice O-rings or this timing belt material? I hadn't
thought
> of trying to make one but might have a suitable belt (I have lots
of junque)
> I could cut and splice.
>
> Thanks
>
> Lew