For basic convex sharpening, a strip of mousepad with a 1-1 /18' strip of sandpaper on top. Use finer and finer grits to hone the edge, for example I use 180, 400, 600, 800, and (sometimes) 1000 grits. A 42x1" belt sander would be even better. After the initial sharpenings, you can finish by steeling the edge or get or make a few leather strops. I made two a month back out of a yardstick, two paint mixers, and an old belt. One strop is loaded with tripoli compound for initial stropping, and the second is loaded with green chromium oxide for final polishing. Once you get the hang of it, you can get your khuk(s) pretty sharp.
Bob