There is nothing more frustrating than having all the ingredients picked out for a gourmet dinner, the counters cleaned for preparation, pulling your knife out of the block—and discovering that it does more squashing than slicing. If you do not know how to sharpen your kitchen knives with a whetstone, it may be tempting to throw your knives in the trash and purchase a new set.
Honing your knife with a stone involves a series of steps that include choosing the appropriate stone, preparing the stone for use, and running the blade’s edge along the stone’s surface.
With experience, honing a knife can become an art, with many sharpened blades more effective than those that are brand new. However, without following the proper steps, attempts to hone your knife can actually cause more harm than good, so do not try sharpening your favorite kitchen knives until you have developed some skill and are confident in your abilities.
How to Hone a Knife with a Stone
Many excellent online tutorials can provide video instructions on how to hone a knife, choose the correct stone, prepare the stone for use, and run the blade along the stone’s edge to get the desired finish.
We’ve included these detailed steps below to help you through the process.
Test Your Knives for Dullness
While the image of throwing a tomato in the air and slicing it five times before it reaches the counter may be possible only in cartoons in tailored infomercials, a good, sharp kitchen knife should definitely be able to pass through food with little resistance.
Therefore, before breaking out the whetstone, be sure to test your knife on a piece of fruit. A tomato is ideal, as its thin outer membrane will pose little challenge for a sharp knife but will provide a troublesome barrier for a knife that has lost its edge.
When testing your knife, ask yourself the following questions:
- Do I have to apply a lot of force to get through the piece of fruit?
- Does the knife pass right through the fruit, or do I have to saw back and forth?
- Does the fruit lose its shape because of me having to press down too hard?
- Are the slices uneven, signaling that the blade is trying to follow the path of least resistance through the piece of fruit?
The more strongly you can answer in the affirmative to these questions, the duller your blade is. Knowing your blade’s dullness is important because it will influence the level of grit required on your whetstone to get it sharp again.
If you do not have a piece of fruit available for testing purposes, the following tips may help you determine whether your knife needs to be honed:
- Gently tap the blade on the back of your thumbnail. If it catches, you have a good edge on your blade; if it slides off, then the knife is dull.
- Think about how you use your knives. If you regularly put them to the test, then they will periodically need to be honed to maintain their edge.
- Think about whether your knife has experienced any trauma recently. Having the blade strike up against another hard piece of metal or clambering in the dishwasher can cause some blades to lose their edge quickly.
Choose the Type of Stone You Want to Use
There are many types of whetstones, both natural and synthetic, that can help you sharpen your kitchen knife. There is no right or wrong answer to which style of stone you should choose, but each type will come with certain strengths and weaknesses.
The following breakdown looks at the pros and cons of popular styles of whetstones:
- Wet Stone – This is the softest style of whetstone. It is made of either natural or synthetic materials and must be soaked in water before use. The softer surface offers more give during the sharpening process, which allows for faster honing times but also causes the stone to wear out more quickly.
- Oil Stone – This style of whetstone must be coated with oil before use. Besides being less expensive than wet stones, this style has a harder surface that will last longer. However, sharpening times are extended, and working with and cleaning up the oil can be a messy process.
- Diamond Stone – This is the most expensive and longest-lasting stone style, as it is actually a series of diamonds set into a metal surface. This stone style can be used dry and is arguably the best option available if you have the budget for it.
If you are a casual user of knives at home, you will likely use either an oil stone or a wet stone. If you use them with great frequency or operate an industrial kitchen, an investment in a diamond stone may be worthwhile.
Select the Stone’s Grit Level
Within the overarching styles listed above, stones will be further classified based on their grit, such as coarse, medium, or fine. It is not uncommon for casual knife users to see a stone with a coarse grit level on one side and a fine grit level on the opposite side.
A general rule is that very dull knives should be honed with a coarse stone first and finished with a fine stone. If your knives have been recently sharpened and are still in decent shape, you can skip the coarse stone and simply finish the edge with a medium or fine grit level.
If you are completely new to choosing grit levels for a stone, the following breakdown will help you while you are making your selection:
- Coarse Stones – These are used on extremely dull and damaged knives. They can get rid of any chips and knicks on a blade and should not be used for routine sharpening due to their abrasiveness. These stones will have a grit grade level of less than 1,000.
- Medium Stones – These stones will have a grit grade level between 1,000 and 3,000. They are used for the general sharpening of dull knives. It is best to avoid grade levels below 2,000 for sharpening, as they can quickly wear through your knife.
- Fine Stones (Finishing Stones) – These will have a grade level between 4,000 and 8,000. Any grit levels closer to 8,000 will be for extremely fine finishing. Knives used primarily for cutting meat should have a finish of around 6,000, while fruit and vegetable knives function best closer to 8,000.
Prepare the Stone for Use
After determining your knife’s dullness and selecting a style and grit of sharpening stone, it is important to read the user’s manual accompanying the product before proceeding, especially if you plan to use a wet or oil stone. With such a wide variety of stone possibilities, using your stone with the incorrect oil or not soaking it in water long enough can damage your materials, causing knicks and scratches to the knife or stone.
- Preparing Wet Stones – If using a wet stone, it should be completely submerged in water and allowed to soak for at least 45 minutes.
- Preparing Oil Stones – Get out the oil you plan to coat the stone with (the actual coating process will happen in the next step, described below). It is best to use oil that is sold specifically as sharpening or honing oil; they are typically fabricated with non-petroleum products and have additives to help preserve your blade. Do not try to use cooking oils to oil your stone.
- Preparing Diamond Stones – Diamond stones are generally the only type of whetstone that can be used dry, so no preparation is usually necessary. However, some water can be used to coat the surface if you choose to do so.
Place the Prepared Stone on a Damp Cloth
Lay a well-wrung washcloth on a level surface, placing your stone of choice on top. If it is a double-sided stone, make sure the side you want to use first is facing up. Ensure that the space is not too confined, as you will need a good range of motion as you run the blade across the stone.
It does not matter which style of stone you are using (wet, oil, or diamond)—it must be placed on the damp cloth. The cloth is important because it will hold the stone in place during sharpening. Placing the stone directly on the work surface could cause slipping as the blade slides across the stone, which may lead to an injury.
The grit from the stone will likely cause staining in the cloth, so be sure to use something that you do not mind getting dirty.
If you properly prepared your wet stone, no additional steps are needed here. However, an oil stone will need to be oiled after it is placed on the cloth. The following are some tips for adding oil to your oil stone:
- Either spray the stone with oil or pour a little directly on the stone’s surface
- Use your fingers to distribute the oil and rub it into the stone
- Make sure that the entire stone is completely coated in oil
- Keep the oil handy so that it is readily available if it needs to be re-applied throughout the sharpening process
Practice Handling the Knife
As most straight blades must be sharpened at a 20-degree angle, it is important that you get some practice holding the knife in this position before actually bringing it in contact with the stone. To get an idea of what a 20-degree angle looks like, take the following steps:
- Hold the knife directly out in front of you, with the blade perpendicular to the table’s surface; this is considered 90 degrees. Conversely, the blade lying flat on the table surface would represent 0 degrees.
- Tilt the knife halfway from this vertical position toward the table surface; this creates a 45-degree angle
- Cut the angle in half once more; this will create a 22.5-degree angle, which is close enough to the desired 20 degrees to begin sharpening. (It is important to note that if you are working with an extremely coarse grit level, you may want to reduce this angle even more, with the blade laying close to parallel with the table surface, to prevent the stone from wearing down the edge too rapidly.)
- Practice moving your arm back and forth at this 20-degree angle to get a feel for what it will be like when contacting the stone.
Hold the Knife Against the Stone
Using one hand, tilt the knife so that the blade is at a 20-degree angle, with the blade’s edge facing away from you. Place the fingertips of your other hand on the flat part of the blade near the sharp end. Keeping your fingertips on the flat end of the knife can provide a stabilizing effect, helping control the pressure and direction of the blade as you guide it along the stone.
Sharpen One Side of the Blade
Now that the stone is prepared and everything is in place, it is time to start the actual sharpening process. Take the following steps to get the desired result:
- Slowly slide the blade down the stone and sweep it in an arc as it moves.
- Draw the blade’s entire edge across the stone, ensuring that it is evenly sharpened from heel to tip.
- If the stone starts to feel dry, wet down the stone or apply some additional oil.
- Complete this process in a repetitive motion until the first side of the blade is sharp.
Sharpen the Other Side of the Knife
Flip the knife over and follow the same process as that of the first side. When putting the finishing touches on the blade, be extremely careful, as both honed edges could lead to an accident if you get careless.
Add the Finish (for Very Dull Knives)
If you had been honing a very dull knife, it is time to switch from a coarse grit level to a fine grit level to put the finish on your blade. Double-sided whetstones can usually be flipped over and used, while separate stones should be prepared using the same steps listed above.
Note: With double-sided wet stones, check to ensure that the fine side has not dried out; if it is dry, dip it in water before use. For oil stones, add more oil to the fine side as needed.
Test the Knife
Before putting away your knife and cleaning up your stone(s), it is important to test and see if you have gotten it to the desired level of sharpness. As mentioned earlier, a piece of fruit like a tomato works well, but you can also use a piece of paper for an extremely quick test.
When holding a piece of paper in front of you with one hand, a sharp knife placed at the top edge should slice all the way through when only a little force is applied. If the blade is still dull, the pressure will cause the paper to fold over on itself.
If you find your knife needs more of an edge, repeat the previous steps, as necessary.
How Sharp is Sharp Enough?
Many knife fans like to keep their knives sharp, to the point where even the slightest touch can draw blood if you’re not careful. While there is no downside to keeping your blades this sharp, the general rule is that your knife should be “sharp enough to do the job.”
For meat knives, this means being able to cut through fat, tendons, and gristle with minimal effort. For fruits and vegetables, you should be able to effortlessly make consistent cuts without squashing the item during the slicing process.
As you work to hone your kitchen knife to the appropriate level, it is important to remember that if the blade is being used correctly and in a safe environment, sharp knives are actually safer than dull knives.
A sharp knife allows you to slice and make your cuts in a controlled, calculated manner. Dull knives that require a lot of force leave you at risk of seeing the knife slough off and chop something unintentionally. Dull blades can also lead to frustration that causes you to lose focus and do something unsafe.
Clean and Store the Knife
After you have the edge of your knife honed to the desired sharpness, it is important to clean both the blade and the stone to prevent rust or corrosion. The following cleaning and storing tips can help you keep your knife sharp:
- Do not run your knife through the washing machine
- Make sure the knife is completely dry after cleaning
- Store the knife in a block or other protective sheath
How Often Should You Hone a Knife?
Honing a knife can become a sort of hobby, with the blade’s glide across the whetstone a form of therapy for some people. As such, it is not uncommon to see some knives sharpened daily.
However, it is important to note that you are taking a small part of the blade’s steel with it every time you hone a knife. Therefore, high-frequency, aggressive sharpening can actually whittle the blade down to nothing if this pattern is repeated over many years.
In terms of general rules, knives made from stainless steel should be honed after every 2 to 4 uses, while blades fabricated from carbon-based steel can be sharpened every other use. If this pattern is maintained with consistency, you should only have your knives professionally sharpened every other year.
One final note on the frequency of honing: if you have a favorite knife showing visible signs of wear, do not try to use a hard stone for honing. Use the softest wet stone possible and reduce the frequency of honing, applying as little force as possible during the process.
Mistakes to Avoid When Honing a Knife
If you are a complete beginner to knife sharpening, there are a few points that may be easy to overlook and cause frustration as you attempt to get an edge on your blade. Avoid the following mistakes as you start your knife-honing journey:
Assume that all Stones Are Universal
The most glaring mistake that beginners make when sharpening a knife is seeing a whetstone and immediately using it with their knife without knowing if it’s the proper type of stone for their blade.
As you have seen, not all stones are created equal, and if you do not understand what you are trying to accomplish during the honing process, the result of using the same stone for all occasions can be maddening.
Choosing a coarse stone for a small blade that needs only a minor touch-up can cause you to wear down the edge prematurely, while using a fine stone for an extremely dull knife will take hours, with the stone likely to wear out long before the blade ever gets sharp.
Choosing the Wrong Stone Size
If you have a large stone and need to sharpen a small knife, you should be fine. However, if you have a small stone meant for sharpening pocket knives and everyday carries, you might run into some trouble trying to work with a full-length kitchen knife.
As honing your knife requires you to run it in a sweeping arc along the stone that roughly replicates that slicing motion, you will likely run out of real estate before reaching the knife’s tip when using a short stone.
Therefore, it is recommended that all stones used for honing kitchen knives be at least eight inches long.
Trying to Substitute Water for Oil
Wet stones that use water as a lubricant are soft and allow the blade to dig into them during sharpening. Conversely, oil stones are hard and need the blade to glide across the surface to create the edge.
If you are out of oil for your oil stone, do not try to cut corners and lubricate it with water. This will actually increase the stone’s stickiness, leading to chipping and scratching of both the stone and the knife blade.
Sharpening at the Wrong Angle
While the general rule is that you should run the knife along the stone at a 20-degree angle, this is not always the case:
- If you are using a coarse stone to hone a very dull knife, a very slight angle, perhaps as little as 10 degrees, may be necessary to sharpen the blade.
- On the other hand, if you use an angle significantly larger than 20 degrees, you run the risk of taking the edge off your knife and actually doing more harm than good.
Starting with Your Favorite Knife
If you have no experience honing knives, it is highly recommended that you do not make your maiden voyage with your favorite kitchen knife. Finding the right angle and getting the right stroke can be challenging in the beginning. If you have a good knife, it is possible to make it worse or even ruin it by sharpening it incorrectly.
As such, develop your sharpening skills using a lesser knife in the beginning. Once you are confident you have the process under control, then you can graduate to sharpening higher-quality products.
How Long Will a Honing Stone Last?
For most users, a whetstone will last forever. Given the proper care, it is highly unlikely that you will ever wear through a stone. Even if you are a high-volume chopper and use your stones every day for some kind of sharpening purpose, a well-cared-for one will last you many years.
With that said, there are a few factors to keep in mind that may lead you to need a replacement:
- Wet stones lose a little surface material during each use and will wear away faster than the harder oil stones or diamond stones.
- Coarse whetstones wear out faster than medium and fine ones. Each granule shed from a coarse stone is a bigger piece of material. Also, as coarse whetstones are used for dull knives, most hard sharpening work is done on these stones, causing them to wear faster.
- The life of stones is commonly referred to in terms of the number of knives serviced and not in time. The coarsest stones have a lifespan of about 20-30 blades, while fine finishing stones can approach 500 blades serviced in their lifetime.
While the process for honing a knife may differ slightly from person to person, the general steps will involve choosing the appropriate stone, preparing the stone for use, and running the knife’s blade along the stone’s surface.
- When choosing a stone, you need to know if you have a very dull blade that needs to be sharpened or a slightly dull knife that needs to be finished. This will help you decide which style of stone to use (wet, oil, or diamond) and the surface’s grit level (coarse, medium, or fine).
- When preparing the stone for use, you will need to lay a damp cloth on a level surface to keep the stone from slipping. You must soak wet stones in water for at least 45 minutes and thoroughly rub oil onto the entire surface of an oil stone. Diamond stones can be left dry.
- During sharpening, keep the blade at a roughly 20-degree angle. Run the knife from base to tip along the length of the stone in a sweeping arc motion. Test the edge after at least five strokes and when satisfied, flip the knife over and sharpen the other side.
A sharp knife should be able to slice through a regular piece of paper with minimal effort. To keep your edge sharp, store it in a dry, protected environment. Hone stainless steel blades every two to four uses and carbon steel blades after every other use for maximum effectiveness.
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