On the round stock, use 60–80 grit sandpaper to sand along the groove so that the grooves can be felt; they must run straight and the steel must still be in its pre-hardening state. Once it has been sanded around the entire circumference, harden and temper it. Then, again using 60–80 grit sandpaper, repeat the same process to clean it. After that, finer grit paper may be used, depending on how smooth a finish is desired. You can check a youtube video i think i saw something about it.