Re: [CAD_CAM_EDM_DRO] Re: optical switch

I just looked at a very respectable source who tested this.
Optos seem to repeat to around 1 micron or 0.001 mm, depending on supply
voltage.

It´s definitely better than most of us need.

Ps.
I build my machines to around 1 micron real-world accuracy, ie. my
theoretical accuracy is around 0.1 micron.
Lathe not mill, as milling accuracy is mechanically limited to around
0.01 - 0.02 mm.

Danny Miller wrote:

>
>
> How accurate is that?
> Optos go through a range over several mm where they partially obscure
> the path between emitter and detector. The exact sensitivity may depend
> on temperature and ambient light leaking in. Which may be fine for a
> limit switch, but may not be accurate enough for a HOME limit switch if
> that's what you intend to use it for. The home position may not have
> highly repeatable accuracy, but I don't know.
>
> Danny
>
> Ron Ginger wrote:
> >>
> > Have a look at
> >
> http://store.makerbot.com/electronics/electronics-kits/optical-endstop-v2-1-kit.html
> <http://store.makerbot.com/electronics/electronics-kits/optical-endstop-v2-1-kit.html>
> >
> > They have a complete kit of PC board and parts for an opto switch for
> > $3. I just bought 10 of them- for $2.70 each- to use as limit switches
> > on a couple projects.
> >
> > ron ginger
> >
>