Cool Tip: Sharp as a ... Knife

Photo courtesy of Photo Review
We’ve discussed why Ceramic knives and tools almost never need to be sharpened, but have you ever wondered why some steel knives need to be sharpened all the time, while others seem to hold their edge for much longer?

The answer, in part, can be found in where the steel knife is on the Rockwell Hardness scale, which runs from 55-66 Rc. For your current knives, you can find that number on the packaging, or the manufacturer’s website.

A lower-numbered “softer” blade makes for easier initial sharpening, but a softer blade will not hold its edge as long and, thus, will require more frequent sharpening and maintenance.

A “harder” blade - high 50s and above - will hold its edge longer, but will require more work to sharpen and maintain its edge. The highest-end Japanese steel kitchen knives are at the harder end of the scale, and therefore have an arguably sharper edge.

There are hundreds of steel alloy “recipes” for knives out there, but they all have a Rockwell rating. Most mass manufacturers of steel kitchen knives currently aim for something in the high-50s range: offering maximum sharpness with minimal care and maintenance.

And that’s today’s knife trivia lesson!