I first started out making knives out of files, and occasionally still do,however the polishing process is the same whether it's files or stainless steel. Once the grinding part is done, then I switch over to various grades of emory paper. Regular old sandpaper doesn't work real well. You didn't mention whether you ground yours on a wheel or a belt grinder. Back when I did mine on a wheel, the first grit was 40,then 80,120,220,320,400,600,1000,1200. Hard to take a file past 1200 'cause the "grain" will start to show. The general rule is you start 2 grits below whatever you had on your machine. Actually, for everyday use, taking it up to 320 will give you a kind of smooth, even finish. Any thing past that is pure polishing. Basically, I'd cut the emory paper into strips that were equal to the width of my blade. For backing I'd use(still use) flat,narrow pieces of hickory that I'd shape out of old axe handles, files(for the coarse grits), files that I've ground the teeth off and flattened, pieces of micarta and so on. The cutting goes faster if you use a little water on the blade, or cutting oil if you have some. Don't use a lot; just a little sprinkle. Cuts faster, and the paper lasts longer. Just keep moving that strip along whatever my backing is until the end, then go to the next one. Keep rubbing until you don't see any grind marks left from the grinder or last grit you used. Sometimes,especially at the beginning, the paper last only two or three swipes at the blade before it's clogged. If you want to really polish the blade, once you get above 320, polish first along the length of the blade, then diagonally across until you don't see the first marks. Takes a while to do. Keep in mind that you're trying to polish a piece of steel that was formulated to resist abrasion. It would take me,back in my old wheel grinding/file days, 14-16 hours to go from 40# to 1200#. Nowadays, things go a lot faster with a belt grinder and using annealed(soft) steel. Do most of my polishing before I send the blade to heat treat. Even so, I still spend from 3 to 6 hours on a blade using the emory paper(to a mirror polish).
