Santoku knife

Today, I sharpened a Santoku knife entrusted by a customer. I had heard that it can be sharpened frequently, and it was already sharpened quite beautifully, suitable for regular use!

The sharpening process for this knife took a bit more time than expected. The tip of the blade was a little thick, so I aimed to thin it out while sharpening. This knife had been machine-polished, and perhaps due to that, the tip of the blade wasn’t sharpened to the fundamental level I had anticipated. As a result, more time was spent than I had initially thought, and I had to widen the blade to achieve the desired sharpness.

The customer emphasized, ‘Prioritize sharpness!!!’ So, I aimed for a straight edge with a decisive sharpening technique. However, converting a double-edged knife to a straight edge compromises the blade’s solidity—not a matter of steel type, but a structural challenge.

Though it’s tempting to go for a bold straight edge with a double-edged knife, it would lead to a precarious edge. Hence, I reluctantly added a bit of ‘Itohiki’ to maintain stability.

Itohiki’s effect is truly outstanding; just a strand of hair’s worth of Itohiki can yield significant results.

Additional note: When the request is ‘Sharper, please!’ you would need to use a rough sharpening stone to thin out the overall blade thickness from the middle of the blade to raise the ‘Shinogi’ line, resembling what’s shown in the photo.

However, this would involve grinding to a point where you practically erase the manufacturer’s name. So, I aimed to maintain the current state as much as possible while performing the sharpening. If it were a single-edged blade, we could achieve a straight edge swiftly.

With the support of ‘Uraoshi,’ even if we slightly grind from the surface, it holds up. However, when sharpening from both sides with a double-edged knife, the blade’s tip tends to sway in various directions.

I believe that if we can sharpen it well, it would cut efficiently, but the degradation in sharpness is quick. It might become a knife that seems sharp only initially, but loses its edge rapidly.

hibishugyo

• 2010-05-28