There's a certain satisfaction in the art of wielding a truly sharp knife in the kitchen. The ease with which it glides through vegetables, the precision it offers when slicing meats, and the joy of knowing you have a trusty culinary companion at your side are unparalleled. But a knife's sharpness doesn't last forever; it gradually dulls with use. Fortunately, a time-tested technique can restore your blade's razor-sharp edge and reignite your passion for cooking: sharpening a knife with a stone.
In this guide, we'll delve into the art and science of knife sharpening, demystifying the process step by step. Whether you're a seasoned chef looking to hone your skills or a kitchen novice eager to learn, we'll cover everything you need to know about using sharpening stones to achieve that coveted precision.
What Is A Whetstone?
Whetstones, or sharpening stones, are made from a variety of natural or synthetic materials, such as quartz, silicon carbide, or aluminum oxide. They come in various grit sizes, with lower numbers indicating a coarser grit size. Lower grit is needed to shape and repair the edge of the knife, while the higher grit sizes are useful for polishing the knife's edge and sharpening it to a razor-sharp edge. If possible, use a double-sided sharpening stone that has both a coarser and finer grit size on the same stone.
How To Sharpen A Knife With A Whetstone
Wet The Stone
Many whetstones need to be completely immersed in water before using them. You will know that the stone is ready to be used when the air bubbles stop coming up to the surface of the water. The sharpening stone needs to be kept wet during the sharpening process because it is necessary that a slurry forms from the combination of water and whetstone dust. This slurry is what actually does the sharpening, so take care not to wash it off when adding more water to the stone. A few drops at a time will be ample.
Set Up Your Station
Place your stone on a towel over a cutting board or on a non-slip mat on your work surface to prevent the stones from sliding during the sharpening process.
Determine The Correct Angle
A professional knife sharpener will take care to determine the exact angle of edge a particular knife needs for its intended use. In general, a smaller cutting edge angle creates a "pointy" edge that is useful for cutting but wears down quickly. A shallower edge is more durable.
To find the appropriate edge angle for most kitchen knives, place the blade of the knife perpendicular to the sharpening stone, rotate it halfway up to create a 45-degree angle, and then reduce this angle again by half to create a 22.5-degree angle.
Maintaining a consistent angle throughout the sharpening knife process is important, so hand placement is key. Use your thumb as a guide to hold this angle consistently, ensuring the thumb never actually rubs across the sharpening stone. Typically, the knife should be held in the dominant hand while the fingers of the other hand are placed near the blade's edge to apply pressure.
Redefine The Edge
Begin sharpening by redefining the original knife edge. Use the coarse side of the traditional sharpening stone, set your angle, and start to slowly drag the knife blade back and forth along the stone. Only apply pressure during the backward motion! Apply pressure when pushing the knife forward to nick your blade. During this stage, you may need to apply a notable amount of pressure, using your body weight to press into the stone during the backward motion.
You will be sharpening the dull blade in approximately one-inch increments, determined by the size of the stone and the width of your fingers that are applying pressure to the side of the blade. Drag each section across the stone at least 10 to 15 times before moving on to the next section. You will know it is time to move on to a new section when you feel a tiny burr forming at the transition from the belly to the edge of the blade.
Once you've sharpened the entire edge of the knife on one side, flip the knife over and commence sharpening the other side.
Polish The Edge
Use a sharpening stone with fine grit, or switch your double-sided stone over to the higher grit number. In this step, you will repeat the process of redefining the blade edge but with a higher grit. This makes the edge razor-sharp, polishing off any small nicks or burrs. Keeping the same angle as before and maintaining an even pressure, polish one side of the knife and then flip it over to the opposite side.
Hone The Edge
Likely, your knife block or knife set came with a honing steel or honing rod. They are often mistakenly used for knife sharpening itself when they really are intended to smooth out the blade at the final step. Pass the sharpened knife edge along the honing steel 2 to 3 times on each side. A leather strop with honing oil applied to it can achieve a similar effect.
Clean and Store the Knife
Thoroughly clean the knife to eliminate any metal particles or debris. Ensure it's completely dry before safely storing it, preferably in a knife block or on a magnetic strip.
Knife Sharpening Tips
There is no need to go quickly. Both a dull knife and a sharp knife are dangerous, and the knife will not be made any sharper by dragging it across the whetstone quickly. A slower sharpening speed will achieve a safer and more thorough job.
Practice On A Lesser Knife
Feel free to practice using a whetstone by using a lesser knife the first few times. This way, a cheaper knife bears the brunt of any scuff marks during your learning process.
Watch Your Thumb
When using your thumb to keep the sharpening angle consistent, take care that your thumb isn't rubbing against the stone itself! You likely won't notice at first, but it will get very sore and painful as the sharpening process continues.
Rotate The Stone
The sharpening stone does wear down during the sharpening process, so take care to rotate the stone often so that it wears down evenly. Otherwise, you may need to resurface the whetstone with a leveling stone.
Keep the Stone Lubricated
Use water for water stones and honing oil for oil stones to keep the surface lubricated. This helps prevent clogging and ensures a smoother sharpening process.
Check for Burrs
Periodically check for burrs along the blade's edge. A burr is a small metal protrusion that forms as you sharpen one side of the blade. You can feel it by gently running your finger along the edge. When a burr is present on one side, switch to the other side and sharpen until you create a burr there as well.
Count Your Strokes
Monitor and count the number of strokes on both sides of the blade. A common technique is to maintain an equal number of strokes on each side to maintain balance.