Re: [CAD_CAM_EDM_DRO] Cheap source of encoders

mjohnson@... wrote:

> Hello!
> I am starting my first DRO, and I am trying to minimize my expense.
>
> I would like to know of sources for surplus or used encoders. I have
> seen a few on ebay. Is there another source?
> I tore apart an HP 500 inkjet printer and found the encoder and strip
> was of 150 cpi, and that is not fine enough. Are there sources in
> other products or different printers? Where else can I scrounge? I
> am in Columbus, Ohio if anyone knows of parts sources here.

Oh, I should have mentioned, shaft encoders are MUCH cheaper
than linear. If you can use a shaft encoder on a leadscrew, you will
get much more resolution. If the problem is leadscrew accuracy and
backlash, then you can use a fine wire or thin metal strip to drive a
rotary encoder from linear motion. Some people have shown projects
which did this successfully.

Jon