Sharpening a single-bevel knife, straight from a maker's print guidebook

Two angles, not one

Jikko's own guidebook separates two things people often conflate: the angle you hold the knife's body across the stone (roughly 45°, for full stone-width contact) and the actual edge bevel angle, which for a single-bevel knife is only about 5–10° — gauged by lifting the spine to the thickness of one or two ten-yen coins.

That's markedly lower than the ~15°-per-side figure Kai gives for double-bevel knives (see our grit-selection guide) — which tracks, since a single bevel carries its entire angle on one face instead of splitting it across two.

Sources: 實光刃物完全ガイドブック (Jikko print guidebook, 2016), pp.23-25

The tip gets its own pass, the back gets almost none

Sharpen the tip first — raising from the elbow rather than the wrist, since the tip sits at a different angle than the rest of the edge. About 20 strokes per position (pressure on the push, release on the pull) until a burr can be felt along the whole edge.

Removing the burr (かえりを取る) is the entire treatment the back face gets: lay it flat against the stone — no angle at all — press lightly, and give it only 2–3 strokes per position. Too much force here just chips the edge.

An optional secondary micro-bevel (小刃付け) exists for people breaking down a lot of fish daily — finishing stone only, barely any pressure, skippable for beginners.

Sources: 實光刃物完全ガイドブック (Jikko print guidebook, 2016), pp.23-25

別打 (betsu-uchi) is a defined steel grade, not a vague label

Community explanations of 別打 (see our grit-selection guide) describe it loosely as 'more effort or different spec than the standard line.' Jikko's own steel-grade chart is far more specific: their 別打 line uses plain white steel (白鋼, not the White Steel #2 used in their top 上作 line) — rated 4/5 for edge quality, 3/5 for retention, 3/5 hardness, 5/5 ease of sharpening, and only 2/5 for rust resistance.

In practice that means: easy to keep sharp, needs more frequent touch-ups than their top-tier steel, and rusts if you don't dry it immediately — which lines up with owners' real-world experience of this line.

Sources: 實光刃物完全ガイドブック (Jikko print guidebook, 2016), p.20

The daily routine that actually prevents the rust

Since 別打's whole trade-off is rust resistance, Jikko's guidebook spells out the after-use routine that's meant to offset it: rinse the blade, pour hot water over the surface so it dries faster, wipe with tissue, then wipe on a thin coat of salad oil (optional but recommended), and store the knife in a dry cabinet rather than a humid room.

For removing the burr specifically, there's a low-tech alternative to the flat-stone pass: roll a sheet of newspaper into a thick tube and draw the blade from heel to tip through it, using the whole edge, at three slightly different spots. Cutting the newsprint this way clears the burr without going back to the stone.

Sources: 實光刃物完全ガイドブック (Jikko print guidebook, 2016), pp.24, 29