Help Identify What This Arbor Fits

[extropic]

Does anyone recognize this arbor and know what machine it fits?

I got the arbor attached to a NOS Albrecht 1/2" chuck.
No OEM packaging came with the purchase, so no clue as to the application.
The arbor is beautifully made, hardened steel, all ground with a fine finish.
The straight portion of the shank is 10mm OD with a special thread (assumed for retention in a spindle)
The special thread is about 9.5mm OD with a course pitch (about 2.5mm) and a special thread form.
The thread form has square flanks on the lower face (toward the chuck taper) and about 45° flanks opposite.
The chuck taper is Jacobs #2.
Overall length is almost 86mm.

Thanks for looking.

 

[ddillman]

Moore taper for a jig borer
I take that back I didn't read close enough the threaded side would need to be tapered

 

[Illinoyance]

Is that a flat on the right side of the shank?

 

[extropic]

Is that a flat on the right side of the shank?

No flat on either the 10mm diameter shank or the Jacobs taper.

 

[Illinoyance]

The shank resembles one for the Moore jig borer, but the photo shows a more slender taper.

 

[extropic]

The 'spindle' end of my arbor is a very precise 10mm cylinder (zero taper).

 

[Uglydog]

I've seen several times where someone took Jig Bore Moore tooling and turned down the shanks to cylindrical so they could be chucked up in any collet. That may have been what happened here.

Daryl
MN

 

[extropic]

LOL
I seem to be developing a small collection of unknown (on H-M) chuck arbors.

What Spindle Does This Fit?

I got the pictured adaptor in an eBay lot. The left side is a #3 Jacobs taper but I don't recognize the configuration of the right side. There are no threads for a drawbar which makes me suspect it is supposed to be retained with a nut. However, there was no nut in the lot. The right side is...

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