View Full Version : What is this?

04-22-2008, 02:18 PM
Recently came across these:


Anyone know what they are and how they are used?


04-22-2008, 02:27 PM
Go/ Nogo inside mike.

04-22-2008, 03:13 PM
They look to me to be a set of tubular (the rods are made out of tubes) bore mics that are set up to be used as a set of G0/NoGo gages.

Each one would probably make a nice mic on its own.

They were probably used as inspection tools somewhere.

04-22-2008, 03:28 PM
Thanks, but how are they used? Do the distance rods screw into the micrometer heads somehow? Or do you just hold the rod in one hand and the micrometer head in the other, and see if they fit in the bore?

04-22-2008, 04:39 PM
They are distance rods and micrometer heads that were used on milling machines and jig bores before the days of DRO's to locate work. They were set in a channel on the table and set for the distance the table was to move.

It is easier to do than say, but they were used to precisely set the distance between the fixed stop and moveable stop. The loose rods set the gross distance and the micrometer head for fine setting.

I have a Bridgeport set made by Tumico with tenth reading mic heads.

Spin Doctor
04-22-2008, 05:02 PM
Plus one end would bear against an indicator that you would zero out.

04-22-2008, 08:10 PM
we call them stick mics, they slip into each other, bit of fine oil,they stay together, my present mitutoyo screws together, much better