On Sat, 03 Sep 2005 14:05:14 GMT, "JimEvans"
wrote:

Those Chinese units use magnetic scales ( like calipers) and have a number
of issues- they are very subject to any liquid contamination, the
connections are poor and the display uses LED's. The Shumatech is a good
way to go if you can source some decent scales and do your own display from
pieces. There is a good optical scale unit at a reasonable price if you are
looking for a turnkey system- they compare to to Mitutoyo, Heidenhahn ets
for quality and features , but much lower cost- go to
http://forums.delphiforums.com/MadeinUSA/start
Actually, the chinese scales use capacitance, not magnetism, to read
the scale. I suppose this is why they won't work when wet. However,
the Mitutoyo water resistant calipers use inductance as the measuring
method.
ERS
"Nick Müller" wrote in message
. ..
Hi,

I just got an offer for Chinese DROs (to fit onto a mill or a lathe),
that are quite cheap. I _would_ prefer Heidenhain, Sony or Mitutoyo, but
not my wallet!
These cheapos seem to have a resolution of 1/100mm, but what's their
accuracy?

I do have a Tek TDS waiting for some waves to sample, a programmer for
uCs, a laptop willing to cycle through some C-code and the knowledge to
put all the things together ...

Nick
--
Motor Modelle // Engine Models
http://www.motor-manufaktur.de