I have a Baldwin DRO on my 9x14 mill from the 70's.
It needed a few chips and one of the nixies replaced.
I got it working pretty well but I noticed that one
of the encoders didn't always read reliably. I took it
apart and cleaned the glass (it needed it badly) and
adjusted the pillow block. It worked better but still
missed a few beats when I tightened the anti-backlash
set screws. So I took it apart again and noticed
that slide moved a bit away from the glass scale when
the set screws were tightened. To fix that I tightened
up the nylon screws that ride on the glass scale. These
nylon screws adjust how close the eye is to the scale.
That left me wondering about the actual process used to
set the distance of the eye to the scale and if it were
incorrect if that would affect accuracy. If anyone here
knows these old units well I'd love to hear from you.

Thanks!

In my limited experience with a few different types of older linear scales,
there can be some very critical measurements.

I bought some used scales that were severely abused, where the reader
head/pickup device had been rubbing on the scales, and ruined the mask that
the precision optical slits are located on.. not repairable.

In addition to the spacing/gap of the head-to-scale, an azimuth adjustment
or setting needs to be verified by precise measurement, or monitoring the
output signals with an oscilloscope, or other means, to determine if the
signals are at optimum levels.

I used to have a lot of online references to various types of optical
encoders and linear scales, but they were on a previously used computer, so
I don't have them now.

A quick search of "BALDWIN DRO" reveals quite a few forum discussions dating
back to 1996 or so.. you might check those, if you haven't already..
otherwise, it may be better to upgrade your DRO to a much newer system.
Almost any equipment made in the 70s is likely to be problematic/unreliable
presently.

Since the DRO readout portion is working OK presently, it may be more
worthwhile to sell it, rather than trying to keep in in operating condition.

--
WB
..........


"sbnjhfty" wrote in message
...
I have a Baldwin DRO on my 9x14 mill from the 70's.
It needed a few chips and one of the nixies replaced.
I got it working pretty well but I noticed that one
of the encoders didn't always read reliably. I took it
apart and cleaned the glass (it needed it badly) and
adjusted the pillow block. It worked better but still
missed a few beats when I tightened the anti-backlash
set screws. So I took it apart again and noticed
that slide moved a bit away from the glass scale when
the set screws were tightened. To fix that I tightened
up the nylon screws that ride on the glass scale. These
nylon screws adjust how close the eye is to the scale.
That left me wondering about the actual process used to
set the distance of the eye to the scale and if it were
incorrect if that would affect accuracy. If anyone here
knows these old units well I'd love to hear from you.

Thanks!