If you take a look at the tip of the spindle at even low mag', you can see that something like 3mm at the core of the spindle is different to the bulk of the metal.
I sort of assumed that the spindle was (probably induction) hardened along the length and at the thrust bearing end, and then ground to size and profile.
But - I have just tried polishing the bearing tip, and it appears to be mighty soft - just a touch with green compound and then blue compound mop has it to a mirror finish. Literally it took me longer to change the polishing mops than it did to polish the bearing. Logically, it looks like the spindle is just hardened along the length/OD.
Should anyone be worried that this might be damage rather than polishing, green and blue compounds are removing truly minute amounts of metal. Having said that, the OD of the spindle looks absolutely fine and if it wasn't, I am not about to try polishing one outside a lathe ........... which I do not have at home.
I sort of assumed that the spindle was (probably induction) hardened along the length and at the thrust bearing end, and then ground to size and profile.
But - I have just tried polishing the bearing tip, and it appears to be mighty soft - just a touch with green compound and then blue compound mop has it to a mirror finish. Literally it took me longer to change the polishing mops than it did to polish the bearing. Logically, it looks like the spindle is just hardened along the length/OD.
Should anyone be worried that this might be damage rather than polishing, green and blue compounds are removing truly minute amounts of metal. Having said that, the OD of the spindle looks absolutely fine and if it wasn't, I am not about to try polishing one outside a lathe ........... which I do not have at home.