End Facing

[Mutt]

I am trying to figure out exactly what lathe tool I need to face internally on the end of a bar. The easiest way I know how to describe it without drawing a blue print is if a freeze plug was on the end of a piece of round bar stock or if ya took a 1½" round bar, chucked it up in the lathe and bored a flat bottom hole in the face of it using a 1¼" end mill. Is this even possible?

 

[Bob Korves]

Welcome, Mutt. Are you saying you want to put a flat bottomed 1-1/4" hole/recess in 1-1/2" stock? If so, how deep? A shallow flat bottomed hole can be made easily with a standard boring bar. Even deeper holes are not that much problem until you get more than a couple diameters deep, just harder to see what is going on in there. An end mill is not needed, but a center cutting end mill would work, you would need to figure out how to hold it.

 

[Mutt]

The recess would only be like 3/16" deep I have a couple of different boring bars, but it seems to me that any boring bar would need some kinda curved relief under the insert, so as not to interfere with the curvature of the i.d. wall

 

[Bob Korves]

Boring bars must have relief below the cutting edge so they do not rub on the work. How about some pics of your boring bars?

 

[Wreck™Wreck]

Plunge a center cutting endmill large enough for your boring bar from the tail stock or tool post a few .001's short of full depth, finish with the boring tool.
Done

The endmill does not even have to be terribly close to center, just close enough that it cuts as the finished ID and depth will be controlled by the boring tool.

This is called a counter bore by most.