Life School
Life School
Knife Sharpening Basics

Knife Sharpening Basics

Today’s lesson is 618 words, a 2 min 28 sec reading time. Subscribe here.

📍 Introduction: 

Knives, when properly sharpened, let you fly through your work with the greatest of ease. You can slice, dice, and chop with the flick of a wrist — no leaning, pushing, or whacking required. 

Conversely, dull knives are difficult & dangerous. They are more prone to slip & slice a finger or palm. They are also slow and tiring to use.  

How do you know if your knife is dull?

  1. You feel like you’re muscling your way through chopping vegetables 

  2. Tomatoes smush when sliced, and juices are running

  3. The edge slips when slicing an onion  

  4. Slicing and chopping feels slow and hard  

When you notice that your knife is dull, it’s time to sharpen! 

There are a few different ways to sharpen a knife. You can use a knife sharpening service - often available at a hardware store or local knife shop. 

You can also use a knife sharpener at home. A simple handheld sharpener typically costs ~$10. Higher-end electronic sharpeners cost more, but don’t necessarily provide better results. They are more aggressive on shaving away the blade so aren’t recommended if you are hoping to extend your knife’s shelf life.  In this lesson, we will cover the two most common types of home sharpening: pull-through & whetstone. 

In the first method (with a basic sharpener), you pull your knife through two pieces of tungsten carbide. This wears away the metal on both sides, creating a new sharp edge. 

In the second method, whetstone sharpening, you slowly grind and shave off bits of the knife by dragging the edge across a stone. Most chefs prefer to use this method as it yields a sharper blade and doesn’t remove as much steel. 

Note - a honing steel does *not* sharpen your knife. Instead, it “hones” the edge, pushing & re-aligning the molecules after they bend out of shape with use. Hone regularly between sharpening for best results. Some chefs will even hone their knife every time they cook.

Once you have sharpened & honed, you should test your knife to ensure it’s sharp. The most common ways to do this are:

1) The Paper Method: cut through a piece of paper held up in the air

2) The Tomato Method: gently slice through the tomato top with little to no force 

📝 Notes, Tips & Tricks: 

  • Knife sharpening can take a while - it’s great for a weekend project! 

  • Vacation is a great time to drop off your knives at the professional sharpener - just leave one at home for the night you return 

  • Know yourself. If you are excited at the idea of sharpening, go big and get a whetstone! If you typically don’t enjoy that kind of thing, invest in an electric sharpener. 

👩‍🍳 Chef’s Note: 

“I'd say that knife sharpening frequency depends on how much wear your knife is getting. A good rule of thumb is if you struggle to cleanly dice an onion, it's time to sharpen. Even though it can be a pain, having a sharp knife will always help you to work more quickly and safely. Investing in an end grain cutting board and using your steel frequently will increase time between sharpenings.” - April Word (5 years at Chez Panisse & Head of Culinary at Thumbtack)

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🎓 Further Study: 


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👉 Next lesson: #37 - Practice: Sharpen & Test Your Knife (Monday, July 20)

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