A double-bevel Japanese knife is sharpened to approximately 15 to 17 degrees per side, a significantly thinner angle than a Western knife (20 to 25 degrees per side). It is this thin angle that gives Japanese blades their cutting precision. Maintaining a consistent angle throughout each pass is more important than achieving an exact degree. A stable, non-slip surface beneath the stone helps maintain this consistency along the entire length of the blade, from the heel to the tip.

Yes. The stone must be submerged in water for 10 to 15 minutes before use, until no air bubbles rise. This saturation prevents the surface from drying out during sharpening. During the session, add water regularly to keep the abrasive sludge on the surface. After use, rinse the stone under running water to remove metal particles and let it air-dry flat, never store it while damp, to preserve its structure and prevent cracking.

Any double-bevel knife, Japanese or Western, is accepted for sharpening on a water stone. Single-bevel knives, such as the Yanagiba, Deba, or Usuba, as well as blades over 300 mm, require a prior in-store assessment before they can be serviced. In the event of a chipped tip or if reprofiling is required, a quote will be provided on-site before sharpening. Chisels and other cutting objects are not covered by this service.

Water stones remove metal through gentle friction without generating excessive heat, which preserves the steel's temper. This point is particularly important for hard Japanese steels, such as Aogami (carbon steel known as "Blue Paper Steel") or SG2 (powder steel), which can become brittle at high temperatures. Electric sharpening grinders can also distort the existing cutting edge. Stay Sharp works exclusively with water stones.