Re: Threaded Rod/Cable Driven Encoders

--- In CAD_CAM_EDM_DRO@y..., "ballendo" <ballendo@y...> wrote:

> Chris,
>
> Not quite like that, but...
>
> If you start with round stock for the nut; drill and tap it for the
> screw, and turn a semicircular depression near one end (can be done
> with a chainsaw sharpening file)
>
> Then you stand it on end (depression end up), and saw partway down
> (making 2 or 4 fingers with one or two sawcuts).
>
> Finally put an o-ring in the depression you made earlier to provide
> the force to push the fingers in... Use an "thicker" o-ring for

more

> force.
>
> Works well. Will be better on acme than american std due to flank
> angle.
>
> Hope this helps.
>

Ballendo, do you mean like this? I built a small wooden router and
used 1/2-13 threaded rod for lead screws. I made the nuts from 1" dia.
nylatron gs barstock. I also polished the screw with valve grinding
compound by running a steel coupling nut up and down about 50 times.
When I was done, I could see movement as fine as 0.0002 with a dial
indicator. (ie 5 ticks back and forth between the 0.001 markings. This
was repeatable anywhere on the screw.)Im not saying its perfect, just
pretty good for under $5.

http://plaza.powersurfr.com/deanc/nylatronnut/

Dean