Nubatama Bamboo 320 Grit: 205x75x30. In this video, I demonstrate the 320 grit Nubatama Bamboo stone. Although I mention the Kikuichi Yanagi, I don't get around to sharpening it in the video (oops).
The stone is not that porous and quickly saturates. It does retain swarf easily, a characteristic that it shares with the JNS 320. The swarf doesn't easily remove even with scrubbing with a nail brush. This doesn't interfere with it's performance. It also gives a relatively shiny finish.
I start off with a Moritaka 'mini nakiri' similar to a produce knife that fruit vendors use for sampling fruit to their customers or testing the quality of their produce. It is a kuroichi blue steel knife, a little more abrasion resistant but ultimately not quite as sharp an edge (a small difference most won't notice). Produces an excellent edge. An excellent match.
I comment on how to vary the stone's performance by water saturation levels, mud level, pressure, etc. I note bubbles coming up, a sign of a stone not completely saturated.
As an aside I comment on having the stone3 stay in place during a video, something I didn't do so well in an earlier review of a 400 grit stone and something I find annoying when others let their stone slide around..
Next I work on the Sugimoto Carbon steel short Chuckobocho. This also produces excellent results, easily yielding an edge tha both slices and push cuts paper well retaining some toothiness too.