Knifeworks 101Comments Off on Knifeworks 101
This is the first in a multi-part series on knife education by Mike Fay, MABA Past President and Pitmaster for Aporkalypse Now.
The cook’s knife. No tool is as simple yet so complex. When you boil it down it’s nothing more than a shaped sheet of material with a handle that has had an edge put on it. From there we have evolved into an almost infinite combination of blade and handle shapes, materials and edge types yet it always comes back to two things; comfort and sharpness. We’ll explore blade and handle type in a future article but for this article we’ll explore the question I get asked the most. “What’s the difference between honing and sharpening?”
To answer this we need to understand what makes a knife sharp. A knife blade is a piece of material (in this article we’re using steel) that has been ground to a point on its edge; usually at a specific angle based on the type of steel used and the manufacturer’s preference.
Looking at an illustration of the very tip of the blade (the cutting edge) shows that edges are usually expressed in degrees from center for half the blade (one edge), in this example this blade has an 18 degree edge.
While the edge of a knife looks like a smooth surface, it’s really a series of microscopic teeth very similar to a saw. The size of these teeth is governed by many factors: the type and hardness of steel and the amount of polish on the edge. Softer steels have larger teeth while harder (and more brittle) steels have smaller teeth.
Remember that these teeth are very small and exist on the very tip of the edge as seen in the illustration above.
When we cut with a knife those small teeth bend, flex and roll off to one side. The result of this is the blade becomes less sharp (notice I didn’t say dull) with usage.
This condition is easily restored by the honing or “steeling” process. This involves gently dragging the edge of the blade against a smooth, hard surface, usually a round butcher’s steel; A smooth, hard rod with a handle. You can easily make on out of a piece of $2 3/8” drill rod and a file handle. Gently (GENTLY) swipe the edge of the knife along the steel as if you were trying to cut a thin slice out of it. Repeat on the other side then alternate each side 6 or seven times to restore the teeth to their upright position. You should do this before you use your knife every time you use it. Remember it’s a gentle light pressure.
Much like knives there is a plethora of stick hones and steels on the market. The best choice is the one that will remove the least amount of metal (those small teeth) from your edge. As referenced earlier, a smooth round steel rod is the best choice. Many steels that come with knife sets or that you purchase have grooves pressed or cut into them. Avoid these. The grooves catch the teeth and tear them off, resulting in your knife becoming dull much quicker and requiring true sharpening.
So what’s the difference between honing and sharpening? Honing is the process of realigning the teeth on the edge of the blade while sharpening is removing metal from the blade thus creating new teeth.
So how do we keep our knives in the best shape over the longest period of time? I typically only sharpen my knives (on a stone) 2 maybe 3 times a year. In between I prefer a hard ceramic honing rod. It gives you the best of both worlds. It realigns the existing teeth and over time will remove just enough metal to keep all the teeth on the blade.
This is the MAC black ceramic hone and to me it’s the best hone on the market.
I’m not a big fan of the oval diamond style hones; I think they remove too much metal.
One of the best sharpening / honing tools for the casual cook is the pull through sharpener. It’s a series of coarse to fine ceramic rods preset at the factory angle. This is one of those tools where you should purchase the pull through from the same manufacturer of your knives. Different manufacturers set different edge angles and using the matching pull through sharpener will give you the best service with the least amount of work.
To use simply pull the blade through the fine groove sharpener 5 or six times using light pressure. If this won’t restore your edge, make a few passes through the coarse groove followed by a few with the fine.
This covers the basics of edge geometry and basic blade maintenance. In the next installment we’ll discuss tool selection, steel types and blade and handle shapes. Happy cutting!