How To Sharpen A Ceramic Knife In 8 Easy Steps
So you've just bought ceramic knives when you had your steel knives sharpened. You loved using them for everything because they're advertised as knives that will stay sharp without sharpening. However, after 6 months, these ever-sharp knives somehow got dull. Maybe it's just a fact of life that knives get dull, even ceramic ones. There are certainly ways to prolong the life of your ceramic knives as covered in the later sections of this article.
Regardless, ceramic knives are considered the black sheep of the cutlery family for this very reason. So here's the dilemma: How to sharpen a ceramic knife without spending a fortune on it.
What Are Ceramic Knives?
A ceramic knife is a knife with a ceramic blade composed of zirconium dioxide. It's produced by dry-pressing and firing the powdered ceramics into solid-state sintering. They're famous for their sharpness, hardness, corrosion-resistance, and longevity. Ceramic knives are supposed to be stay sharp knives. Regardless, they cut so amazing because they're harder than anything aside from a diamond. However, hardness doesn't equal unbreakable. A ceramic knife is actually brittle.
A ceramic knife can get chipped or snapped in half if you apply too much pressure on one side. If a diamond has a hardness level of 10 then ceramic knives has a hardness level of 9.5. In contrast, steel knives have a 6.5 level of hardness and bone has 3.5 level of hardness. Nevertheless, your ceramic knives will whittle down to dullness if you use it to cut bone regularly. With enough time and abuse, any knife will dull down even if it's ceramic. You can either buy new knives or sharpen them cost-effectively.
Can Ceramic Knives Be Sharpened?
Yes, they can. This is because ceramic knives to get dull and thusly require sharpening if you don't wish to replace them immediately with new ones. It's a common myth to think that ceramic knives never need sharpening and won't ever become dull. With enough abuse, they can get dull in half a year or sooner. As time passes by, the blade develops chipping or small chips on the edges that dull it down.
The good news is that ceramic knives don't need to be sharpened as often as steel knives. The bad news is that it's very difficult and/or expensive to do so. You need a professional or a very fine diamond sharpener if you want to sharpen a ceramic knife in particular. How long a ceramic knife needs sharpening depends on usage. It can go months or years without sharpening.
What Tools Can You Use to Sharpen a Ceramic Knife?
There are a number of tools available that you can use to sharpen your ceramic knife. Here they are.
- Water for lubrication
- Diamond sharpening rod
- Diamond wheel sharpener
- Whetstones or waterstones
- Magnifying glass for inspection
- Ceramic knife sharpener system
- Fine to very fine diamond sharpener stone
Stick with diamond stones when it comes to sharpening tools for your ceramic knife. Anything diamond, really. After all, it's the only material harder than ceramic. Technically, you can use other knife sharpening types like whetstones and sandpaper, but they're not highly recommended over diamond sharpeners.
It simply takes less effort to use diamonds on your ceramic knife's edge than with other less hard materials. You also won't be tempted to speed things along by applying more force, which usually makes things the situation worse instead of better. It's simply a question of quickness and efficiency. You can also hire someone to do the sharpening and busywork for you, but it will cost you.
How To Sharpen A Ceramic Knife
1. Ceramic Is Hard Yet Brittle So Brace Yourself:
The trouble with sharpening ceramic knives isn't that it's impossible to do it's instead quite difficult to accomplish. It's an absolute chore to have to sharpen something that's harder than bone and steel, thus requiring you patience and elbow grease as well as diamond sharpeners to ensure you're using something harder than ceramic to sharpen its knife edge.
Although a ceramic knife lasts long and looks great, it's also incredibly brittle. Not quite like chalk but you will get chip damage on it over time or with enough abuse. It's actually easier to break than a steel knife despite its hardness. You should use 200-grit diamond sharpeners for large chips on the edges, followed by 600-grit, 1,000-grit, and then finally 1,500-grit sharpeners to really restore the sharpness of your dull blade.
2. DIY Ceramic Sharpening for Beginners:
If you wish to sharpen a ceramic blade by yourself, there are several things you need to keep in mind first. One, you should buy a diamond sharpener yourself. You have the option to get a ceramic knife sharpener system or tool that costs about 10 bucks and looks like a cross between a can opener and a stapler. You can also avail of a diamond wheel sharpener that the pros use with the caveat that now you should know how to use it.
Although it was suggested in the previous article to first use a 200-grit sharpener, for most dulled ceramic knives you will tend to get the 1,000-grit diamond sharpener with a diamond size that is 6 microns or smaller. Go for less than 1,000-grit for big chips or breaks on the edge. These cost from ten to sixty bucks and are available in sporting goods stores, woodworking stores, hardware stores, or online stores. Expect to undergo a lot of effort in restoring the edge; that's par for the course.
3. Pro Tips for Advanced Ceramic Sharpening:
Restoring the edge of a ceramic knife is painstaking and hard, which is why those with enough money will tend to opt for having the pros do it for them. You should also clean and lubricate your sharpener first before use or else the raw surface will scratch the surface of your knife to the breaking point. Try to match the angle of the edge as you sharpen it since its angle is different from the rest of the tool.
You should also be prepared to rub the knife using light pressure about a dozen times then rinse off the ceramic particles on the diamond sharpener. Literally rinse and repeat the sharpening many, many times until your knife returns to its original sharpness when you first bought. Furthermore, use a magnifying glass to inspect the edges while keeping in mind general knife-sharpening rules.
4. General and Specific Sharpening Rules:
If you're skilled at using sharpening stones or rods for your steel knives you already have a leg up against those who are sharpening knives for the first time. Knife sharpening is about selecting the proper coarseness of the sharpening stone, selecting the right angle, applying oil or water to the stone, and then sharpening the knife. A sharper angle results in a sharper knife until its edge chips off of your food.
A blunter angle will last longer but won't cut as well as a sharper knife. Find a balance between bluntness and sharpness. With that said, there are two main differences in sharpening a ceramic knife versus a steel knife. One, you need to be more careful with a ceramic knife because putting too much lateral pressure on it will make it snap. Two, unlike with steel knives, no burrs will form when you've reached the proper point on the edge of a ceramic.
5. What You Should Never Do When Sharpening Ceramic Knives:
Never apply too much pressure on the blade laterally because you heard it's almost as hard as diamonds and think you can't break it as though it's made of the fictional metal of adamantium like Wolverine's claws of Marvel Comics fame. Don't just use one hand to move the blade and the other to hold the stone when sharpening a ceramic knife.
Just a touch too much lateral pressure will snap your ceramic knife in half. Position your hands the proper way. Control the pressure you're applying by using one hand to hold the handle and the other to move the blade along the stone. Also, because the burr will never form when sharpening the knife, don't bother using that as an indication you've sharpened it enough. Instead, use the magnifying glass or try cutting something to test the sharpness of the knife.
6. What to Always Do When Sharpening Ceramic Knives:
Position your knife with both hands and apply consistent light force with your fingers. The blade should be supported and you should be careful not to laterally exert pressure to snap it in half. You will know that you're doing this right when zero flex occurs or if the knife doesn't bend as you sharpen it. Steel knives have more flex to spare in comparison, making inadvertent snapping less likely.
You should hold the blade with both hands and keep your whetstone or diamond sharpening tool or diamond sharpening wheel as your anvil of support. As far as stones are concerned, it makes no tangible difference when moving your hands up or down as you sharpen. You can go up and down, only down, or only up and it won't matter. The final result is that you'll get a sharper knife. Just make sure the pressure is slight and the movements are smooth and you're good to go.
7. Hiring a Professional Sharpener:
A professional sharpener is a certified specialist who gets paid lots of bucks in order to competently sharpen your ceramic knives as good as new. Just make sure that when you're searching for someone whose services don't amount more than the ceramic knives you've bought or else you might as well just throw those away and buy new ones. A typical knife sharpener person has a powered diamond wheel.
The expensive wheel allows him to streamline the sharpening process and cater to multiple clients with many sets of knives every time. He also knows everything there is to know about the basic rules of sharpening, such as sharpening the edge at an angle that's different from the rest of the blade in contrast to the edge of a typical steel knife. He even knows several things you won't know regarding knife sharpening to boot.
8. Prevention Is Better Than The Cure:
These ceramic knives should never get dull unless you're cutting diamonds or other ceramics unto them. In fact, using a metal, glass, or ceramic cutting board might be the reason why your ever-sharp ceramic knife isn't as sharp as the day you bough them. Use a bamboo or wood cutting board and push less when using such knives to prolong their sharpness. Also, avoid using too much pressure on the blade laterally or it will snap in half.
By the way, there's a myth about how knife turn lettuce brown when cut instead of torn. It's allegedly better to tear the lettuce along its natural seams rather than use a knife to cut it because its edges turn brown faster (and the knife might get dulled as well). This is a myth and regardless if you use a really sharp ceramic knife or tear by hand, the lettuce edges will turn brown at the same rate. Slicing a wet lettuce is likelier to make the steel knife go brown in rust, though!
Knives made of steel might not be as hard as ceramic knives, but at least you can sharpen them with the whetstone or steel rods before having them ground to sharpness. With ceramics, it's a whole different ballgame. It's not as if it's impossible to have your ceramic knives sharpened. It's just that sharpening them professionally will cost you a mint if not an arm and a leg.
Is there a way to sharpen knife at home rather than have a pro do it for you for big bucks? Yes, but it takes patience and skill you might not have. However, if you want to go the DIY route, you can use this guide as your instruction manual in how to do it right. Or you can use the literal instruction manual that comes with a ceramic sharpening tool that's usually geared towards novices.
Did you enjoy the tutorial? Have you learned how to properly sharpen knives or would you rather a pro handle everything? What do you think? Please share your feedback in the comments below and share the article if you like it.