But for what?

Hard to say for sure without being able to see both ends. I will guess at a Micrometer Head missing Attachments.

Hi there Lou,
I sort of expected that about needing to "see both ends." But I couldn't seem to get a shot of em in focus when I stood the darn thing on end. Finally hoped someone would recognize it on plain sight. So now I tried setting the ends in my Venlic vise.
I wondered the same thing about it being a part as opposed to the whole. But then at only 52mm it fits real nice all by itself in its custom made box. Dovetailed at that.
Hal

Hmmm, so it measures 50mm closed and 75mm all the way out? Looks like it may have been a specific application Inside Mic. Or, special order. No luck with the stamped numbers.

The middle picture (DSCF1579); that end opposite the gnarled half, rotates continuously either direction. 52mm length  remains constant.

  It's an inside micrometer.  Just an inside version of the one we're more used to seeing.

 

Well Thank You Navaja. I'm sorry I didn't see this till now. Any thing you can tell me on how you go about using it for this intended purpose? For me it's like not knowing which end of the gun to hold.

I suspect that it's for accurately measuring the inside of a specific size cylinder. Here is my Starrett inside micrometer set with attachments for measuring the inside of almost any size cylinder.
-Don

Quote from: d42jeep on March 04, 2024, 08:15:43 AM
"I suspect that it's for accurately measuring the inside of a specific size cylinder." 


Well Don, you've cleared up some things for me. Obviously, this micrometer cannot do a darn without these attachments. Just what discipline or profession is this particular inside measuring involved in?
-Hal

It's a little outside my experience which is mostly automotive but they could be used by a machinist for measuring bore wear on any kind of large cylinder.
-Don Houghton

Quote from: d42jeep on April 01, 2024, 09:05:53 AM
It's a little outside my experience which is mostly automotive but they could be used by a machinist for measuring bore wear on any kind of large cylinder.
-Don

Thanks a lot Don. I'll tell ya how I came by this. My son was helping me get some chucks from Online Auction. We didn't know how to go about it, so he said, Let's test both the seller and our abilities. He found this "micrometer" for cheap offered by the same seller. It all worked out, so it was a go for the chucks.
-Hal

Quote from: d42jeep on April 01, 2024, 09:05:53 AM...they could be used by a machinist for measuring bore wear on any kind of large cylinder.

Like, say, the bore on the diesel motor of a railroad locomotive.  I inherited my inside micrometer set, which I've never had occasion to use, from my uncle, who was a machinist/mechanic for the Southern Pacific line.

reminds me a bit of this....got this a long time ago when we moved into a house and i think the prior owner had been a machinist.

Quote from: Bill Houghton on April 04, 2024, 12:28:53 PM

Quote from: d42jeep on April 01, 2024, 09:05:53 AM...they could be used by a machinist for measuring bore wear on any kind of large cylinder.

Like, say, the bore on the diesel motor of a railroad locomotive.  I inherited my inside micrometer set, which I've never had occasion to use, from my uncle, who was a machinist/mechanic for the Southern Pacific line.

My Great Grandpa and all six of his sons worked on the railroad. My Grandpa was 14 when he started. He was a welder. At least some of his brothers were machinists/mechanics. They started when it was steam locomotives. Youngest may have been diesel all the way through. His son too. Eire Railroad on up into when it became the Eire Lackawanna.

Quote from: p_toad on April 05, 2024, 04:18:34 PM
reminds me a bit of this....got this a long time ago when we moved into a house and i think the prior owner had been a machinist.

Sure looks like it to me. Bigger cylinders for sure. Thanks.