Another what is it

[gonzo]

OK, here is a cutter that I can't figure out what it is used for. ( dumb asp )
The end it is sitting on is female threaded.

 

[ch2co]

Deburring tool?

 

[JimDawson]

The cutter shape is similar to a wood countersink for a drill/countersink bit. My best guess.

 

[chips&more]

I believe the end that is not pictured has a threaded hole? And a better pic of the other end would show it in a “V” shape. So, that would make it a screw-on internal threading tool. And of course you would need the rest of the boring bar to make it all work…Dave

 

[gonzo]

Dave,
At first I thought you had nailed it but,
It looks like it was designed to be sharpened but,
The diameter diminishes as you go around and thus would defeat the purpose unless the shank or work had a circular motion.

 

[gonzo]

Dave,
Oh wait! Now I get it.

 

[chips&more]

That’s the way they designed it. If you want to, go ahead and redesign it to your liking. If it was the same all around the business end, then it could not go into the smaller holes…for one example.

 

[Chiptosser]

I have a small set of boring bars like that, was used with a Fosdick boring mill.

 

[brino]

Hey @gonzo

That looks remarkably like my item #2 posted here:
http://www.hobby-machinist.com/threads/help-identifying-some-accessories.20889/
(a few years ago now!)

I have since determined that it is indeed an internal threading tool for lathe use. In fact, the same store I got mine at had another with the entire boring bar holder that it mounts to.....so I took a couple more photos:





-brino

 

[gonzo]

Neat, I have several of these and can make my own boring bars for them.
Thanks everyone for the comments.