Re: [CAD_CAM_EDM_DRO] Lengthening Digital Calipers

ptengin@... wrote:

>
> They make blocks just for this purpose. If you have a set of large
> OD
> mikes, you may alrady have the standards for those in the boxes. They
> sometimes have spherical ends and in that event would be hard to use.
> But,
> should they be square ended units, they may be just the ticket. BTW, I
> think
> Bridgeport used to sell a kit to bolt on a series 1 that did just
> that. It
> had a long groove into which the gage rods were inserted. A large dial
>
> indicator was mounted on the end. I believe the old Moore Jig Borers
> had this
> set up too.

I used a set of gage blocks to check the accuracy of my mill. I used a
large
machinist's square, and aligned it with the X axis by putting a dial
test indicator
on the spindle and running the indicator across the beam of the square
until there
was no change in the dial reading. I could then place gage blocks in
the inside
corner of the square, and check every inch, again using the
spindle-mounted
indicator to take a reading off the last gage block.

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. It was VASTLY easier
to use,
and about 20 times faster than the measuring system. Since it didn't
expose
gage rods to shop swarf, the glass scale just held accuracy, while the
measuring
system was constantly being threatened by having swarf get between the
rods.

Jon