What is it? I actually do not know.

[Dave H (MI)]

Name visible. Knurled knob at top, the threaded part comes inside slightly when turned. There is an outdent in the center that would appear to hold some specific item. The threaded rod at the bottom has an allen wrench pocket on the end to turn it into the 3/8 diameter hole (set screw). Aluminum body with steel hardware, making it not out of the question that this was home made as aluminum and brass are favorite materials for home machinists. But it is well made and could be commercially produced. No other markings. Body is 3 15/16 from flat to flat under screws. Inside diameter is too small for a Starret 25 series indicator and too large for the 80 series miniature indicators.

This came in a box lot of other tools. All were machinist setup items. I can tell you I have no idea what it is or does.

 

[jimg.allentown]

Only a guess, but it looks like a special fixture for mounting a dial indicator on a work piece. Probable very specific to the job.

 

[Eric in IL]

If the size is correct, it might fit a Bridgeport style milling machine spindle.

Possibly then used to be rotated to tram the head of the mill to the table.

 

[Dave H (MI)]

Would have to be a specific indicator. Does not fit Starret indicators that I own.

 

[Dave H (MI)]

Would that tie into an indicator tool post in some way? I was thinking the 3/8 hole with the set screw was for an indicator post. I don't really have two reliable reference points that I trust to measure the inside diameter.

 

[Doug-Iowa]

I always enjoy the what-zits, but probably some sort of special fixture. Nearly every project that comes thru our shop needs one or more special gaging fixtures for machine setup or QC. They are made to fit the exact need at the time, and typically their purpose is pretty obvious when complete or in use with a part or machine. Once the job is run out, they go on the shelf. Then a new job comes along and useful parts like scales or dial indicators get cannibalized, leaving only the custom bits behind. Soon the leftovers become unrecognizable, and eventually get tossed in the scrap barrel . If they do get out in the wild, they become what-zits for someone to ponder.

 

[Eric in IL]

You would need to mount an indicator in some fashion.

If you search for Indicoil Bracket you can get a better idea what I am thinking it might be.

 

[Eric in IL]

I spelled it wrong, Indicol should be right.

 

[Dave H (MI)]

Maybe...but if I were doing something like that I doubt I would stop and punch a name on it. A possibility though.

 

[Mike(NEOhio)]

Shop-made version of commonly used clamps to put an indicator on a machine spindle.

 

[Dave H (MI)]

So this is a little different than the commercial ones in that the hole for the indicator is 90 degrees off...vertical instead of horizontal. But I can see where you could get there and mount a test indicator. Best answer so far and seems to be a consensus. Unless someone comes up with a different idea.

 

[Janicholson]

Vice or fixture crisply parallel to bed travel requires a solid fixture to the spindle. + or- .0005 may not be good enough in some cases. This would make a simple solid fixture attachment point. Locking the spindle, or the spindle Quill is necessary. I need 3 of them. One for a Hass VF2 SS one for a Dyna Mite, and one for both a Sharp and a Brown and Sharp 3 Axis mill. Jim

 

[Mike(NEOhio)]

Memory is a bit foggy these days but I knew that thing looked familiar. Had one on the Moore jig grinder. It clamped to the quill above the spindle for indicating holes or centers. That's a home made version.

 

[miangus]

I have one that's similar. Handy.

 

[Dave H (MI)]

Well I guess it's a keeper. I will tag it so I remember and put it in the drawer with the setup parts.

 

[Ozlander]

(quoted from post at 11:34:15 12/19/21) Name visible.

I think it was made by K R LaFontaine.