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The Sad Truth About Kitchen Knives

Section One: The Sad Truth About Kitchen Knives

To a chef, there is nothing more important than his knife. It is not only an extension of his hands, it is an extension of his very personality. The knife is a chef’s paintbrush.

So why are most kitchen knives so bad?

The knives found in most commercial and home kitchens are designed for the lowest common denominator. The manufacturers of these knives make a series of compromises calculated to keep the largest number of people happily using their knives for the longest period of time. Like supermarket tomatoes bred for sturdiness and uniformity rather than flavor, these compromises seriously degrade the performance of your knives.

The first compromise begins with the steel. Steel is the heart of the knife. Most manufacturers (Henckels, Wusthof, Forschner, et al.) have proprietary steel blends and are very close-mouthed about the actual formulation of their steels. According to industry insiders, these steel blends are closely related to or equivalent to a steel known as 440a. By and large 440a steel is formulated for stain and wear resistance rather than holding a high performance edge.

In the kitchen, that’s not a bad tradeoff.

But this compromise in edge performance is compounded by a heat treatment that leaves the steel much softer than it could be. In general, the harder the steel, the keener the edge it will take. However, a hard steel makes it more difficult to get that edge in the first place. So manufacturers leave the steel a little soft, theoretically making sharpening at home easier. If you’ve ever spent an hour or two trying to get a super fine edge on a cheap kitchen knife, you’ll know that there is a big gap between theory and practice.

Upper-end kitchen knives like Henckels, Sabatier, Wusthof, et al., are a little better, but are still softer than they need to be at 52 to 56 on the Rockwell C scale (the Rockwell scale is a scale used to measure the relative hardness of different solids). By contrast, Japanese knives tend to be around 61-62 on the Rockwell scale. Custom knife maker Phil Wilson hardens his S90V (a stainless supersteel) chef’s and filet knives to 62-63 Rockwell.

The next compromise is in the factory edge angles. Most kitchen knives come with an edge that is at least 25 degrees per side, frequently even greater. If you add the two sides together you get a 50 degree included angle. And that’s the best case scenario. Take a look at a protractor if you happen to have one lying around. Fifty degrees is extremely thick. An angle that obtuse is more appropriate for an axe than a chef’s knife. Again, the theory is that the thick angles will allow the edge to resist damage from impaction, rolling and wear better than a thin edge. But, as the song says, it ain’t necessarily so.

Finally, there is just plain cruelty and misuse. While I’m certain none of you would ever use the sharpener on the back of an electric can opener, or use a glass cutting board, or store your knives loose in a drawer or put them in the dishwasher, it does happen. And when you add soft steel and thick angles to the general abuse that knives see in the kitchen, you end up with tools that are more adapted for bludgeoning oxen than fine dicing a soft tomato.

Take heart. The news isn’t all bad. We can fix these problems. Geometry is far more important than steel. With some basic knowledge and the willingness to invest a little time, you can realistically expect a dramatic increase in knife performance.

First, do no harm: General knife care

- Use wooden or composite plastic cutting boards only. Glass, ceramic, marble and steel will cause the edge to roll or chip. Bad. Don’t do it.

- Don’t drop your knives in the sink. Not only is it a hazard to the person washing dishes, but you can also blunt the tip or edge.

- Don’t put your knives in the dishwasher. The heat may damage wooden handles and the edges may bang against other cutlery or plates.

- Keep your knives clean and dry. Sanitize if necessary.

- Do not store your knives loose in a drawer. Use a block, magnetic strip, slotted hanger or edge guards. The magnetic strip is not recommended if you have children or inquisitive pets.

- Finally, your knife is not a can opener, a screwdriver, a pry bar, box cutter or hammer. There’s a special place in Hell reserved for people who abuse their knives this way.

Resized to 81% (was 600 x 522) - Click image to enlarge

If your knives won’t fit in a block, simple plastic blade guards are a good solution

Second: Modify for performance

This is the easy part. Establishing and maintaining high performance edges is what this tutorial is all about. It can be as simple as steeling with the proper technique or as complex as creating specific edge bevel and edge aggression strategies for each knife in your collection. It’s all up to you.

While you can’t change the steel your knife is made from, you can certainly keep your knives at peak performance – and without too much difficulty. We’ll discuss high performance edges and sharpening strategies a little later in the tutorial.

Third: Modify for comfort

This is something very few chefs (and even relatively few knife makers) take into consideration. Ask any chef to show you his knife-hand calluses. He’ll have a thick one at the base of his first finger from the “pinch grip” used in most kitchens. He or she may also have another on the side of the second finger where the finger rubs against the bolster or dropped portion of the blade that extends below the handle.

He will also have aching hands and possible repetitive stress injuries.

In the interest of economy, most knife manufacturers leave the spines of their knives squared off. The edges of the spine can sometimes be sharper than the knife itself. That edge cutting into your finger can lead to blisters, calluses, reduced circulation, numbness and injury.

If you ever handle a chef’s knife made by Canadian knife maker George Tichbourne you’ll know that it doesn’t have to be that way. Tichbourne worked with several professional chefs when designing his kitchen knife series. One of the key features is a smoothly rounded spine. It doesn’t abrade your finger, cut off the circulation, make your hands numb or create any of the other discomforts associated with standard kitchen knives.

You can do the same in less than half an hour. Lock your knife, edge down, into a padded vise. The padding doesn’t have to be anything elaborate. Two pieces of flat rubber or leather will keep the jaws from scratching the blade. You’ll need a sheet of fine (600 grit) wet/dry sandpaper available at any auto supply store or an abrasive cloth, sometimes called a crocus cloth. Using a gentle shoeshine motion, lightly round the edges of the spine. You don’t have to buff hard or remove a lot of metal. All you need to do is break the sharp edge at the base of the spine. How far you take it is up to you. This simple modification will make a world of difference in the comfort of your knives. 

Cherto | info [at] cherto [dot] be | T +32 (0)491 34 08 97