Re: [CAD_CAM_EDM_DRO] Re: best type of hub for pulleyts (DONT USE A KEY)

grouchy_old_fred wrote:

>--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@p...> wrote:
>
>
>
>>Yes, this is why I always buy the pulleys with holes smaller than I
>>
>>
>want and bore them ...
>
>Jon, How do you indicate on the pulleys to bore them?
>

I don't. I just put them in a good 3-jaw chuck, and find a rotation of
the pulley
that puts a "land" under each jaw. (Sometimes, this is real hard to do,
so you
have to wrap a heavy shim around the pulley, or turn a ring and split it
to make
an accurate pseudo-collet.) I figure that if I can get the bore
concentric to
.001" or so, then it is good enough.

Jon