Bizarre, and completely baffling.
The baffling part is what makes it so intriguing. I have to say I have never seen multiple seemingly unrelated brands on any tool before. I have seen multiple brands on tools in situations where it makes sense - such as Whitman & Barnes and Williams, Westcott and Keystone, and even some where it is a little strange, such as Kent-Moore and K.R. Wilson, who competed in the same military specialty tools market. And multiple logos where one is a forge mark (e.g., the circle-B Bonney, or the diamond-H Herbrand) and one is the brand (e.g., Bethlehem Spark Plug Company, Ford, etc).
But this Expansive Bit is crazy.
"CONVAL" is Connecticut Valley, by the way, and they owned the patent (1,056,670).
My bet would be that the "B.H. & M. Co." is Bridgeport Hardware and Manufacturing, and, if you don't know it, "Blue Grass" was a brand used by Belknap Hardware, which made some of its own in-house tools (mainly cutlery or farm implement related) and contracted out the rest. They would not have the capability to make these bits, and if the "Blue Grass" and "B.H. & M. Co" is together, my bet would be that was their supplier for this piece.
I suppose I can see a history in which it was made by one OEM (let's say, CONVAL) but supplied by another (let's say, Bridgeport), or, made by Bridgeport for CONVAL. Those two stamps would not be that strange.
Off the top of my head, I don't know what "H.S.B. CO." is, and I have no idea why there is a CRAFTSMAN stamp on it as well.
EDIT: H.S.B. Co. is Hibbard, Spencer, Bartlett, another hardware store line!
I suppose it's possible it got re-sold as NOS to another retailer (i.e., re-branded), and apparently another after that, without ever touching an actual user's hands.
If it was mine I would be googling the heck out of a few the terms together in different combinations hoping to find a connection.
Or, as you guys suggested, someone having fun with die stamps. But where would he get them?
