Compound rest threaded circular dovetail

[Dustin beyer]

Can anyone please tell me why the circular dovetail is threaded thru center and

 

[piper184]

I could only guess that it was for some sort of specialty tool post where you wouldn't be using the compound slide.
Radius turning tool?
Tool post grinder?
Heavy duty lantern tool holder?

What make and model lathe is that?

 

[Dustin beyer]

It is a Logan 955 11” lathe and same conclusion I think but I have never seen one with the top slide like I did and to separate the two sides especially when attached to the lathe is no short or easy task

 

[benmychree]

It's one of the great unsolved mysteries of our universe, and maybe others as well, for all we know ---

 

[matthewsx]

Make something that fits on there and show us what it’s for.

John

 

[Martin W]

Milling attachment, tool post grinder?