I successfully sharpened the 10 inch blades of my old AP-10 shortly after getting it. The guy who sold it to me thought it didn't work anymore and didn't know what was wrong. When I Iooked at the blades I knew what was wrong. They looked like they'd never been sharpened. About as sharp as a butter knife. So I used my Worksharp 3000 on them without any special jig. Worked well. I later replaced them, temporarily, with a spare set I bought before sharpening the originals and the spare set seems to be softer steel. I like the ability to sharpen the blades, saves some not insignificant money.