I may go with your suggestion Okapi and put a lining in the cup for the bearing with my next one as I want to explore tempering at some point for a hobbing project down the road. I aspire to make tooling of Stefan Gotswinter calibre one day, but I'm still cutting my teeth as a noobie engineer/machinist, so keeping things to an attainable level to start with :p
Right now I'm currently working out my setup to drill the four concentric holes in the cup. My mill is still not up and running yet (waiting on a reamer) so will be using my lathe again.
https://s3-us-west-1.amazonaws.com/f...he/98819-1.jpg
The cross slide doesn't have enough travel to hold the broach shaft in a jacobs chuck, even the 4 jaw makes the cross slide overhang too far, so I've ordered a 12mm 2MT collet in order to bring the cup in close enough to work on.