Re: [CAD_CAM_EDM_DRO] Lengthening Digital Calipers

ptengin@... wrote:

> In a message dated 06/09/2000 8:52:17 AM Hawaiian Standard Time,
> jmelson@... writes:
>
> << It sounds like you are referring to the ANCIENT Bridgeport-Starrett
>
> measuring
> system, which used gage rods and a dial indicator for measuring
> distance
>
> of table motion. This was before Vericheck (I think that's the name)
> invented
> the optical readout system that Bridgeport sold. >>
>
>
> Jon,
>
> I ain't that old. I saw the unit in a catalog many years ago yes. I
> have
> seen them for sale in used machine tool places. So I know they
> exist... I
> thought Vericheck was the system that assures checks don't go rubber
> ;)

I was afraid I was confusing it with that. Now I remember, it is
Ver-i-Scope. The
only deficiency with the Veriscope (referred to by a lot of people as
"Bridgeport Optical
Readouts" is there was no way to have a sign, and the zero index was way
over at
the end of travel. You had a small adjustment of over an inch, so you
could line up
the part edge with some whole number. That way, your (0 ,0) reference
was at
something like (9.000 , 4.000). Still, it was a fantastic improvement
over reading the
dials on worn Acme screws! I could cut stuff and have it come out
within .001"
of what I wanted, INCLUDING tool and part deflection!

But, seeing how much trouble the zero reference business caused with the
optical
readout, I can't imagine using the rods and dial indicators, with chips
flying all over
everything! Just the thought of having to stop in the middle of every
cut to swap
rods (and hope you assemble the right combination) makes me shudder!

I do have some old Bridgeport catalog pages from the '50s that shows the
rod
measuring system.
I have never seen one, although I have seen a few optical readouts still
on machines.
I picked up an optical readout for $15 at a scrap yard and nursed it
back in to
operation. It had been rained on, and the scales got corroded in spots.

Jon