Hard Turning cutting a bearing race

[John Evans]

Haven't had one of these jobs lately so brain fade left me out on how exactly I did this the last time. Job: cut down the worn inner rear wheel bearing race and fit a hardened repair sleeve. For you kids pre 48 Fords used a cylindrical roller bearing who's inner race was the hardened end of the axle tube. 70 years on many of them are slap wore out in that area. Like I said took me a bit to figure out my set up and tooling needed. This bearing race is in the R50-60 Rockwell ,didn't check with my "hardness files " to see for sure ,but in the Woodpecker lips area for sure. Previously I just used carbide inserts to do the job ,but recently had some ceramic inserts gifted me that would work on this job. I have a bunch of square ceramic inserts but the only holder I have for them would not work on this job. I ran this job a bit slow so I did not spray red hot chips all over the place,so stringy chips were a better deal. .020 depth of cut at .004 feed. Great finish . .040 depth at .008 was no sweat except for the *&*(^( chips. Lathe was my ENCO 18X40 .Original OD was 2.060 ,needed to cut to 1.702 for press fit.
PS Ceramic works real good cutting down HSS end mill shanks to fit R-8 collet sizes.
PPS You can see in the third picture where the hardness stops buy the change in the finish,I would suspect induction hardened. Was still hard after .150+ depth of cut.

[spro]

Dang ! Anyone can say nice work and fleet past to another discussion. I will be looking at your pix for days. I would need to read exactly and learn from it.