Are You Destroying Your Expensive Kitchen Knives?

We’ve all been there.  You’re standing there in your favorite kitchen store gazing longingly at the knife of your dreams, when everything around you gets quiet.

Suddenly you picture yourself standing in a world-class kitchen slicing through vegetables with the greatest of ease.  Julia Child is off to the side, watching in wonder as you julienne carrots with incredible speed and accuracy.  Could it be?  Is that a tear of a admiration tumbling down her cheek?  Of course it is.

If I had a dollar for every time this little fantasy played out in my head…

But seriously.

Expensive kitchen knives hold a great deal of allure for anyone with aspirations of becoming a serious home chef.  After all, how can you possibly express your full creative potential when limited by cheap cutlery you’ve had since college?

So you decide to INVEST in a world class chef’s knife.  And an investment it is.  You can literally spend MANY hundreds of dollars on a good chef’s knife such as a Shun, Henckel, or Wüsthof.

Then you invest in a beautiful wooden knife block to hold this magical new tool.  Perhaps bamboo?  No, too hard.  Better go with maple.  Ahhh, just right.

Then after a few weeks you decide your knife isn’t quite as sharp as it used to be.  So you decide it’s time to sharpen it.  You bring out your trusty electric knife sharpener, and TOTALLY DESTROY your blade.

don't destroy your knives

Your Electric Sharpener Is Damaging Your Knives Beyond Repair

Electric knife sharpeners operate on the same basic principle as the sharpening stones of old.  But there are several HUGE differences that cause them to perform more harm than good when it comes to returning your blades to their original razor sharpness.

Any sort of sharpening is going to remove a small amount of metal from the blade.  This is just the nature of sharpening.  But it’s how electric models perform this task that makes them so terrible.  Read on for all the gory details.

Ruining the Temper of the Blade

When your knife was first created it was forged from steel.  Through the process of hardening and tempering, knife manufacturers create a delicate balance of strength and flexibility in their blades.  During tempering the top (dull side) of a blade is heated to a higher temperature.  This has the effect of “softening” the steel so that it is less brittle.  The sharp side of the blade is heated to a lower temperature.  This allows it to retain the hardness necessary to hold a sharp edge.

When you run your blade through an electric sharpener those spinning wheels that speed up the sharpening process also generate heat.  While it may not seem like that much, this localized heat can very quickly damage the delicately balanced steel of your knife.  The result is a softer steel exactly where you don’t want it.  Right along the cutting edge.

Creating an Inconsistent Edge

But wait.  It gets worse.  Because it is nearly impossible to apply consistent pressure as you pull your knife through the sharpener, you end up with some spots that are heated to different temperatures all along the length of the edge.  This creates inconsistencies or waves in the shape of the blade.

The speed at which you pull the knife through also has an impact on this localized heating.  You can try to be as consistent as possible, but the margin for error is VERY small.

Changing the Angle

Most chef’s knives are around 20 degrees.  Some Japanese knives go down as low as 15 degrees.  When the manufacturer of your knife originally designed it, they chose a specific type of steel to pair with a specific angle.  Generally speaking, the sharper the edge, the harder the steel needs to be to ensure durability.

Most electric sharpeners utilize a one-size-fits-all mentality when it comes to the sharpening angle.  This is usually around 20 degrees.  However, there is a good deal of room for error here as you have to pull the knife through the sharpener at exactly the same angle each time to ensure consistency.  This too is nearly impossible.

Ultimately what you end up with is a blade that lacks any sort of angle consistency along its length.

And what if you’re knife has a different angle altogether?  Now you’re re-profiling your edge to an angle for which the steel wasn’t designed.  Not a good situation either.

So what does one do?

The Proper Way to Sharpen a Knife

This is going to be hard for some folks to hear, but traditional sharpening stones are far and away the best method of restoring the edge on your expensive knives.  I can already hear all the complaints:

  • I don’t know how to use a sharpening stone
  • It takes too much time
  • I’m not skilled enough to maintain a consistent angle
  • My dog just said Mylanta

I know.  Tough cookies.  The fact is, if you use an electric sharpener, you will significantly shorten the useful life of your knives.  So let’s take a look at the alternative.

Using Sharpening Stones

Sharpening stones have been around for thousands of years.  From the time Grok first figured out he could rub one rock against another and created something he could cut with we have utilized sharpening stones to fashion any number of tools.  If cavemen could do it…

The basic principle is quite simple.  Starting with a lower grit stone (most abrasive) you push the edge of the blade along the stone.  Just make sure to hold the blade at the same angle as what is currently on the knife.

This causes friction which removes a small amount of metal from the blade.  Eventually the metal on the very edge folds over forming a burr.  You then flip the knife over and repeat the same process.

Next you move onto a slightly less abrasive stone and repeat.

The biggest challenge in all of this is that holding the knife at a consistent angle CAN be challenging for beginners.  But there is a solution.

Duh!  Use a Knife Sharpening Stone System

Thanks to some incredible human ingenuity and the modern miracle of the internet you can now sharpen your knives using a sharpening stone WITHOUT having learn how to hold the blade at the correct angle the whole time.  In fact, there are several sharpening stone systems out there which take care of this for you.

Check out the Top 3 Performing Models

You simply set the angle and run the stone across the surface of the knife as prescribed in the instructions.  There are a couple different methods depending on the model you choose, but the general idea is the same.  Here’s an example of one.  The video’s not terribly exciting, but you can quickly get the gist of how it operates.

What About Speed?

OK.  These products are NOT as fast as an electric sharpener.  That being said, they are much faster than using traditional stones.  A knife that is in relatively good shape can be sharpened in only a few minutes.  And remember, this is accomplished without damaging the blade in any way.

If you want to learn more about these systems, check out this article where we break down the pros and cons of the top selling models.  Once you’ve learned how to properly use them you’ll be able to restore a razor sharp edge on your blades in no time.

Other Options

Another option is to use a local knife sharpening service.  One caveat to be aware of is that many services use a bench grinder.  This can cause the exact same damage to the tempering we discussed earlier.  So make sure your sharpening service is reputable and only uses stones!

References:

http://www.jayfisher.com/Knife_Care.htm#What_about_powered_sharpeners_and_systems

https://en.wikipedia.org/wiki/Knife_sharpening