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Selection and Care of Quality Knives

Quality Knives.

Quality knives come as a mixed blessing for most people. The cruel fact is that the better the knife, the more prone to damage due to mishandling. First of all let’s talk about what constitutes a “quality knife”. The answer is surprisingly complex, and what is true for your household, may not be true for your neighbor . The problem boils down to how well the knife resists dulling from cutting food, as well as how well the knife resists chipping and damage from handling.

The very best knives justify their claim by being made of better materials raised to a higher hardness. Chrome alloys, such as stainless steel, are excellent at resisting wear but are a bit more difficult to raise to high hardness levels. High Carbon alloys are much easier to heattreat, but if raised to a higher hardness, tend to become excessively brittle. As a rule, any knife above Rockwell hardness of 56Rc is too hard to touch up on a normal steel, so this is a practical maximum for professional knives in North America. Some Japanese knives go well above this hardness and use some exotic alloys, and can cost well over $100. This represents the upper extreme in knives. It is my personal opinion that these are not suitable for the average North American household. They should be rinsed immediately after use and placed in a protective cover for storage. They should be sharpened on a wet stone, in some cases of 4,000 and 8,000 grit. Some can be sharpened on a ceramic rod. A handheld carbide sharpener is a disaster on these knifes and may rat up the edge by chipping it to look like a saw. In summary, they require some special method of free hand sharpening at home which is difficult for most people.

Knives that are excessively hard, (over 55Rc) tend to chip their cutting edge very easily. This means that if the knife is placed in a drawer with other things or left out on the counter top or in the sink, the cutting edges will contact the other things, producing a chipped spot. Unfortunately, these conditions are normal around most households. Hence a “better knife” is a mixed blessing. A stainless steel knife of reasonable hardness may be the best bet. Most certainly if you have teenagers or if you have several people using the cutlery, you really don’t want ‘the top of the line’ knives.

High Carbon-Low Stain alloys are high carbon alloy with a bit of chrome and/or nickel added. This makes for a good durable knife, but beware of the “low stain” part. They will corrode or pit if left in acidic water. The knife may develop black pits along the blade from Galvanic corrosion. This can occur due to the knife being left in a bucket of water containing tomato or lemon juice. I have run into this at resturants especially, but also with households that leave the knife in the kitchen sink.

Most “older” knives are made of plain carbon steel, often with simple wooden handles. These knives develop a dark patina that may look rather ugly. If you clean them up, the patina comes back in short order. You can even it out by polishing the old patina off and then placing the knife (blade only) in vinegar or water and lemon juice for just a short while. At least the patina will be even. These old knives are quite durable really, and some have been in households for many years.

In short, it may not be smart for you to buy the really expensive knives, especially if you have been having problems with your old ones. First find out what the problem really is. Most likely you will find it was behind the handle.

No knife, no matter what the manufacture claims, should be placed in a dishwasher. They can rattle around in there like in a shotpeen machine and really dull the cutting edges. The hot-cold, wet-dry cycling can loosen handles, especially those that are riveted. Just being left in water will damage wooden handles from expanding when wet and contracting when dried out. Knives should be rinsed off immediately after use and placed in a block, on a magnetic strip (carefully, not to hit other knives), or in a case or sleeve individually for storage.

Sharpening.

Most people sharpen knives too often and too heavily, whether they need it or not. With freehand sharpening, this means the cutting angle on the blade will change into a cutting radius, because you tend to wiggle, and your blade is never sharper than your biggest wiggle. It may feel sharp (heaven forbid) but not cut as it should. When you are crushing the tomato instead of cutting it, this may be the problem. The knife should be restored to the correct, straight, cutting angle. Most of the handheld sharpeners have problems with this, worsening with time. Someone with a good eye for the correct angle and a steady hand can do this on a sharpening stone, but best to see your professional sharpener for a good trueing up. Attempting to sharpen on a bench grinder is a huge no-no. The excessive speed generates heat that will remove hardness from the micro edge during sharpening. Yes, long before you see any discoloration. The knife edge will begin to loose hardness at any temperature above 350F. Straw color discoloration means it has reached 700F. Blue means 850F. The hardness is long since gone.

I am asked often what kind of cheap sharpener do I recommend? I have to answer: “None of them. They all have problems, sooner or later”. “None of them really work. That’s why there are so many of them.” Anything that I would care to recommend uses small Cubic Boron Nitride wheels, often called Diamond wheels. These little crystals on a relatively slow wheel, do an excellent job and there is usually a built-in correct angle guide. A good machine costs over $100. Hence, no easy answer.

 

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Walt and Eileen Galer

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