Re: [CAD_CAM_EDM_DRO] Re: DRO encoders- Rotary or Linear?

On Tuesday 29 October 2002 06:39 pm, you wrote:

> Instead of using a rack and pinion, would it be possible to use a rigid bar
> (like 1" or 1.5" drill rod) and a rubber roller mounted to a rotary
> encoder? With a solid bar, wipes could be used to clear the surface before
> the roller passed over it, unlike the rack and pinion where clearing it
> would be a difficult measure at best if something were to get in the teeth.
>
> John

This is essentially what a Trav-a-Dial does, except the roller is steel, not
rubber. The company that makes them, Southwestern Industries, also makes a
CNC control called a ProtoTrak which uses position sensors based on the same
principle. See:

http://www.southwesternindustries.com/

Matt