I use the pin as an example .......I realise I should have been more specific.......turn bearing steel,52100,at ex packet hardness,say 58-63 Rc.I know CBN inserts will do it,but would like a recommendation for an insert.....Another question.....will small oil holes in the hard surface chip the insert..............And I do know all about grinding.....I have a whole grinding workshop sitting in outdoor storage.....yes,I shoulda done it then......but I didnt .