Joint pin ID

[daniel]

Anybody know what this strange pin is on a kikel cue?

 

[Michael Webb]

Anybody know what this strange pin is on a kikel cue?View attachment 659182

Looks like an acme maybe 3/8x10, but I've never seen one in brass.
Will the shaft for it screw on to a regular 3/8x10?
The shafts for a regular 3/8x10 should not screw on to this butt.

 

[DeeDeeCues]

Acme screw. Used for power transmission. Found on machinery to move loads. Invented in late nineteenth century because it is easier to machine than square thread profile.

It has a lot of value in cue making, but shouldn't ever be used in a pool cue.