I picked up 2 Nakayama stones from Metal Master in Japan a few weeks ago. One was a long skinny 4.5 and the other was a rectangular one approx 6x4" or so (can't remember exact size off the top of my head!) and rated as level 5. I have a Nakayama koppa from another source and it was so so, never really blew me away with how it performed. I used it as a slurry stone for my Ozuka Asagi because I never liked the edge off of it. My go to stone was an Ozuka Asagi that was probably a 5+ and needed a good slurry to really do much of anything.
I had a Gottleib Hammesfahr 6/8 round point and my Ralf Aust 5/8 Round point to touch up, so I decided to use the Nakayama stones on them, one on each blade. RA got the skinny one, GH got the harder, more rectangular one. I worked up a quick slurry and then went to town. Beautiful feeling when sharpening, nice and creamy feeling. I worked each one a bit on the stone and washed off/wiped down the blade and then pulled out the 20X loupe. Nice, clean edge, no white line at the edge like I usually get with synthetic stones (J Nats seem to knock off any wire edge for me with the slurry I think? Synthetic stones, I get a white line at the very edge at certain angles, J nats with slurry, white line goes away). Pulled out the 60X lighted loupe and checked the edges. Very nice scratch pattern to the bevel (that matte bead blast look from J Nats I love!) and the edge looked dead straight..much straighter than my previous attempts. Stropped them up, looked great under magnification! Tree Top arm hair test was next. They were able to top arm hairs with much less tug and ping than I usually experience! Shaving was nice and smooth, too! I even nicked my ear lobe and felt the blade brush against it, but didn't feel the pinch of a cut. Still cut myself, but didn't even realize it until the blood was dripping! Time to try them out on more blades!
Just goes to show you that each stone is different and may perform completely differently than another one, even though they share the same names!! These edges were by far the best and most comfortable edges I have gotten on any blades yet!
