Restored, those things work great! Dismantle it, re-bush/bearing it... and it'll run when there is no power. Like after the apocalypse! Those units are awesome!Hand crank knurling tool was also an early guess and it might do that but Royal Brass is still in business and does a lot of tubing stuff. May stick something soft in it and see how it does but it looks like the two top rollers will take out the knurling in the middle. An old roll groover also seems plausible and more along the lines of what I was thinking.
Something else that followed me home from the swap meet just to clean up and hang on a wall.
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