what is this thing for?

I don't think so Frank, it does look like a spoon bit. But the shaft is not ... well doesn't appear to be on the centerline of the hole it would cut. If you were to drill a deep hole you would end up with the handle/brace turning in an arc, not staying centered. At least that is how it looks to me.
 
I don't think so Frank, it does look like a spoon bit. But the shaft is not ... well doesn't appear to be on the centerline of the hole it would cut. If you were to drill a deep hole you would end up with the handle/brace turning in an arc, not staying centered. At least that is how it looks to me.

Couldn't we just writ that off to being a Neanderthal thingy?
I guess we still have an 'I dunno'. :dunno:
 
Frank, that looks like a chairmaker's bit. As has already been mentioned, it fits into a brace and is used for drilling tapered holes for spindles with tapered tenons.
 
NO Expert here, but I think it is a spoon bit (fits and auger Brace) that is used for boring a tapered hole for a cast tap or bung hole for a keg or barrel. (depending on how large you bore the hole)
 
Not to be indelicate, but it looks to me like a "bunghole reamer". It turns the straight sides of a bored hole into a tapered hole that will accept a "bung" - a tapered cork or wooden plug. I have one with a small T handle to be used without a brace. The bunghole can be in the side or top of a barrel.

That's my story an I'm sticking with it ;)
 
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