Need info on old Starrett Micrometer

Was wondering if anyone could give me any information on this Starrett Micrometer? It goes from 2.6 to 4.7. I have no idea what it would measure.

We'll try again.
Where in Nebraska? Do you know where it came from?

That is a special Starrett even down to the numbering on the barrel. Somebody paid a lot of money for it new and I'll bet not just one or two were made. If you got in Nebraska, I'm thinking Cornhusker plant in GI or NAD in Hastings.
JR

Perhaps trying Starrett customer service might give a lead?

I'd have to agree government ammunition manufacture as a likely source. I could see the center post in a primer pocket and the two outer detents above the flange. But that could just be an overactive imagination. Martin also had a factory outside Omaha that built B26 and later B29 planes.

In addition to Cornhusker Ordinance and Naval Ammunition Depot, there was also the Nebraska Ordinance Plant between Lincoln and Omaha.

That mike is made to set the tool on an IC engine boring bar. The peg goes into the center bottom of the head, the ball detents hold it in place, and the tool is adjusted out to the mike face. If you check it should read double of actual movement. That one looks like it came from a Storm machine.

Ed.

Please tell us EVERY marking that appears anywhere on the instrument. I can see hints of markings on the black "business end" in addition to the calibrations. I'm going to ask you to PLEASE be as accurate and detailed as possible in this description.

Note that there are three spherical bearing points....the one opposite the plunger is on the _far edge_ of the post. So, that point is to measure the distance from an edge to the _far side_ of a hole or feature. The two bearing points on the arms are used to measure the distance from an edge to the _near side_ of a hole or feature.

And, yes, I agree with GBent that it seems to be used to measure something round with a hole or feature near the center. With a little bit of shop math, you could calculate how accurately the hole was centered and if the hole is not supposed to be centered, you could calculate where it is in relation to where it's supposed to be.

This micrometer is a very interesting collectible tool!

On Edit: Looks like somebody beat me to it!

John Ruth

Give the cigar to the man from Wisconsin. I think he's got it.
JR
BTW, I'm about 7,000 miles from home if you want that cigar.

I'm in northeast Nebraska but I have no idea where I purchased this. It came in a box of stuff at an auction but I have had this for quite awhile so really don't remember. I have attended auctions in Nebraska & southeast South Dakota. Thanks for the reply

The marking in the black part are hard to photo but I tried.thanks to all who relied, Bob

atex57 said:

That mike is made to set the tool on an IC engine boring bar. The peg goes into the center bottom of the head, the ball detents hold it in place, and the tool is adjusted out to the mike face. If you check it should read double of actual movement. That one looks like it came from a Storm machine.

Ed.

Click to expand...

Concur

cheers

Carla

Ok, thanks to all who replied. I definitely do not have a boring machine so with this information I have decided I will probably just go ahead & sell this on ebay. Thanks again, Bob