CNET también está disponible en español.

Ir a español

Don't show this again

Appliances

Sharpen and care for your kitchen knives

Dull kitchen knives are trouble. Sharpen them often to make cooking faster and safer.

Chris Monroe/CNET
Now playing: Watch this: Keep your kitchen knives sharper and safer
1:58

If you bought a nice knife for your kitchen, congrats! You took the first step toward making cooking easier and more enjoyable. But, don't stop there -- a good knife deserves careful maintenance, like sharpening and honing.

After a few weeks of use, new knives will become dull, forcing you to apply more pressure to make cuts. That added resistance doesn't just mangle meats and veggies; it's a potential hazard for your fingers.

Keep your knives feeling new and your fingers safe with this guide to sharpening and honing cutlery.

Disclaimer time: I'm stating the obvious, but knives can hurt you. Even if you don't plan on servicing your own blades, handle them with care. The smallest of paring knives can cause a big injury in a flash. Always exercise extreme caution and mindfulness around these sharp implements -- for your sake and of those around you. I'll also focus on steel knives since ceramic blades typically require professional servicing.     

Honing and sharpening: know the difference

These two terms are often used interchangeably, but they're actually different. Honing refers to the act of straightening a blade's existing edge. Over time, and through ordinary use, the edge of a knife blade will curve over slightly or bend out of its original position.

Honing

When you hone a knife, you coax its pointed surface slightly back into position. It's a gentle fix but when done often, can prevent more serious blade damage.

The most common way to hone a knife, is with a honing steel.  These inexpensive tools ($10 to $30) are essentially steel rods with a handle. The surface of the rod is coarse, and scraping a blade across the rod (at the proper angle), on both sides nudges (hones) its edge back in place.   

Sharpening

Sharpening is the practice of aggressively polishing a knife to reform its edge. You'll need to do this for very dull knives only. In the process, bits of metal are actually shaved away. That's why sharpening a metal blade calls for material harder that steel --- stone or ceramic. It's also why you should hone often, but sharpen rarely.

A honing steel is a tool used by many professional cooks to realign knife blades. 

Chris Monroe/CNET

Hone your knife

A honing steel, relied on by many professional chefs and cooks, is a common tool for honing kitchen blades. Using a steel properly though takes practice to get right, so don't be discouraged if your first results aren't obvious. Here's how to hone your knife:

Start by placing the end of the steel's rod on flat surface (table, counter, cutting board).

Next, while holding the steel's grip with your non-knife hand, place the heel edge of your knife onto the steel. Make sure to angle the blade between 15 to 20 degrees --- in relation with the steel rod. Also rest your fingers (holding the knife), safely on the knife grip (behind the heel).

Now drag the blade downwards along the steel. At the same time, pull the knife carefully towards you. The motion should move from the back edge of the knife to its tip. Maintain the same angle throughout your stroke. Repeat this action three to four times. Next do the same on the knife's other side.

Sharpening knives with a whetstone is the old school way.

Chris Monroe/CNET

Sharpen the blade

Whetstone

To reform the edge of your knife blade, you'll need a tougher tool. The old school way is with a whetstone. And costing between $15 and $20, it's an affordable method too. To begin, place a square of damp paper towel on a flat surface. Rest the whetstone on that, it'll keep it from sliding.

Wet the knife blade with a little water. This lowers friction. Now place the knife on the stone (its coarsest side), at a 15 to 20 degree angle. The tip of the knife should point away from you. Rest your fingers on the flat of the blade (except your thumb). Your thumb remains on the handle grip.

Drag the knife across the whetstone in a circular motion, making sure to keep the angle constant. Do this three to four times. Flip the knife over and repeat. Next, do the same procedure but on the whetstone's smoother side. Your once-dull kitchen knife should now have a sharpened edge.

Electric sharpeners  

You can use an electric sharpener too. The process is much the same, with the added benefit of speed. Instead of a whetstone, these products have both honing and sharpening slots. Dragging a knife through the slots accomplishes the same task.

Grinding wheels spin inside the slots, and are spring loaded. That means they should polish knife edges at the correct angle automatically. Expect to pay a little more for a motorized sharpener, in the range of $30 to $40 (via Amazon). The company also sells a line of kitchen knives, under the same EdgeKeeper brand, with sleeves designed to "sharpen" their blades every time you use them. Most likely they're honing, not sharpening their knives but it's helpful nonetheless.

Surprisingly, the bottom of a ceramic cup works as a blade sharpener in a pinch.

Taylor Martin/CNET

Ceramic mugs

It sounds crazy, but we've tried this ourselves. Flip a ceramic mug over, so its bottom faces upwards. Place it on a flat surface. There should be a ring that's raised, and unglazed. The ring's surface is rough and is harder than steel. Use it as you would a whetstone. If things go badly, you might scrape and mangle the blade edge useless. Try this on a cheap knife, not fancy cutlery.      

Call in the pros

For some, sharpening their own cutlery is too much hassle. Many premium knife brands such as Mac offer sharpening services (Mac brand only). With fees ranging from $5 to $14 per item, it's reasonable too. Still, you will have to ship knives back to their facility. That means you'll have to do without it for as long as 7 business days.

Some local grocery stores and supermarkets will sharpen your knives too -- and often for free. Usually you can ask at the butcher counter, preferably during off peak hours. Like any untried sharpening method though, try it out on a knife you could live without first.