[tcovington]

I am having a hard time locating a tool to do what I need with out having to have one custom designed. I was hoping someone may know something that could help me.
We have a part that has been rough bored to 2.6" and needs an ID groove that is finished at 4.724 in diameter and has a total lenth of 3.6". I'm lost on this one, Please advise.
Thank you in advance!!

[Superman]

Might be a bit awkward to do it with a CNC & with one tool

4.726 - 2.6 = 2.124 / 2 = 1.062 radial step ( cutting edge projection from b'bar shank )
2.5 - 2.124 = 0.374 ==== maximum shank diameter of b'bar

ask for a re-design, ( possibly.... add a c'bore on the end to allow a ring to be screwed into place )
( that much undercut seems like a lightening exercise )

Another option is use a manual lathe, with a bar that takes a square HSS tool that can be adjusted outwards