This is my step drill AKA reamer sold to me in the 80,s (all you could buy those days for7mm pens I treat this like gold,I face off on a 12 inch sander and this drill is still a snug fit in the blank and as you can see from the four blanks it lightly reams the hole and cleans it thoroughly.. If you find a firm capable of grinding one from a HS Reamer please share with me. Also see some of the terms used by Pro Firms this one claimed within a fraction of a mm of measure in the US but failed miserably.I negotiated by phone with the owner of Fuller even got an IAP member to deliver a Slimline brass or three for a go no go guage.
Peter.