The speed and polishing ability of waterstones attract many sharpeners. Waterstones sharpen quickly and are available in fine polishing grits not found in other stone types. The ability to flatten the stones is a necessity when sharpening with waterstones, so a starting set should include a flattening stone of some kind. Our article, How to Flatten a Waterstone, has more information about keeping waterstones flat.
However, it should also be noted that “water stones” are generally significantly softer than oil stones and thus, water stones generally cut faster than oil stones but, they also have to be flattened more often that oil stones do. Furthermore, it should be noted that some water stones must be soaked in water for several hours prior to use whereas, others are of the “splash and sharpen” variety and thus, they only need to be soaked for a few minutes before use and then wetted down occasionally during sharpening process. Diamond hones on the other hand are more durable than either water stones or oil stones and, because they generally have a more coarse grit, they cut faster than natural whetstones. Plus, due to their construction, they never need truing and, in fact, coarse diamond hones are often used to flatten both natural and synthetic whetstones.
Different knives are sharpened differently according to grind (edge geometry) and application. For example, surgical scalpels are extremely sharp but fragile, and are generally disposed of, rather than sharpened, after use. Straight razors used for shaving must cut with minimal pressure, and thus must be very sharp with a small angle and often a hollow grind. Typically these are stropped daily or more often. Kitchen knives are less sharp, and generally cut by slicing rather than just pressing, and are steeled daily. At the other extreme, an axe for chopping wood will be less sharp still, and is primarily used to split wood by chopping, not by slicing, and may be reground but will not be sharpened daily. In general, but not always, the harder the material to be cut, the higher (duller) the angle of the edge.
If you do not remove enough metal to create a new edge, you will leave some of the dull edge in place. A dull blade (or a blade with dull spots or nicks) will reflect light from the very edge of the blade. A razor sharp knife edge will not show "bright spots" when you hold it blade up under a bright light. You will need to remove enough material from the sides of the bevel so that the edge stops reflecting light.
I'm a novice knife sharpener. I've had to unlearn what my grandpa taught me in order to use these. So far, I've had decent but mixed results. I've switched to my cheap 200/400-ish cheap tool stone from harbor freight for cutting a bevel when the blade has either been damaged or did not have a proper bevel. The 400/1000 grit stone in this kit is soft. Very soft. I have bowled it out several times. It makes keeping a steady angle difficult. But these stones at this price point are meant for learning, and for that they serve their purpose.
Hold the knife in your right hand (or left) with your index finger along the spine of the knife and be comfortable, hold it tight enough so it doesn’t move as you sharpen but you don’t need a death grip on it. Wear shoes and if possible stand on a mat that will absorb the impact of the knife if you drop it. (You won’t drop it but be safe…..move your feet if you drop it!).
Removing the burr is fairly simple. You'll need a leather strop or block (this sort of thing), which is designed to catch the metal fibres from the knife. You could do it with a fibrous tea towel or some newspaper if you like, but I'd suggest going with leather to begin with. The motion is fairly similar to sharpening. Draw the knife over the leather, going away from the edge at roughly the same angle as when you sharpened.
Rest your knife on the stone at your chosen angle. An easy method for determining the angle by eye is to visualize a 45 degree angle and then take half that amount. That will give you a ballpark estimate of the angle and then you can adjust accordingly up or down. With a slicing action bring the length of the knife across the stone with a motion that starts with the heel of the knife on the stone and ends with the point of the knife. The motion should resemble a sweeping arc pattern across your stone. Be very careful to maintain the angle of the knife on the stone. Longer curved knives provide additional challenges but as long as you can maintain the angle you will be sharpening very effectively. Repeat this process on the other side of the knife and continue repeating until you have sharpened your knife though all your stone grits.
Ceramic sharpening stones were the early replacement for natural stones. Unfortunately there are huge differences in the quality of ceramic stones so be wary. Some are extremely soft and dish out very quickly and at the other end of the spectrum some are so hard they tend to glaze over in a hurry. Ceramic stones need a good soaking for about 10 or more minutes to saturate the pores of the stone prior to use. As all knife steels are different we tend to find that ceramic stones tend to work better with some knives over others. There are no hard and fast rules but we like ceramic for Ao-ko and single edged knives. The Kaiden Ceramic stones are the fastest cutting Japanese stones in Australia and are recommended for advanced users.
Low Grit Stones: A sharpening stone with grit number less than a 1000 is generally used for knives and tools that are damaged. If your blade has any nicks or chips in the blade, the stones will take care of them in a jiffy! They usually have a coarse side for nicks and chips, with the other side for general sharpening. Even if the knife’s edge has become totally blunt, the stone will re-sharpen it perfectly.
A: That depends almost entirely on how often you use them. If you are a professional chef who uses his or her knives every day then you should hone them every time you use your knives. But honing has its limits and over time your edge is going to become dull no matter what. Therefore your knives will need to be sharpened at least several times a year. Some chefs, in fact, will use a whetstone on an almost daily basis in order to ensure their knives are always razor sharp. Most of us, however, are not professional chefs and may not even touch our kitchen knives for days at a time. In that case, it’s probably a good idea to hone the edge after every couple of uses and have your knives sharpened once a year.
These are very popular stones. 8" Dia-Sharps have a single grit per stone making them more expensive, but at 8" by 3" they are wider than the 8" DuoSharps, offering a good working surface. The 8" Dia-Sharp line also has the widest range of grits available from DMT, with extra extra coarse, medium extra fine and extra extra fine options not available in other sizes, so it is good line to consider. One coarse and one fine stone is a good starting point.
This wedge ends up short of a "point" to a much larger degree than the picture would indicate. The metal stops short, but then there is black non-slide "tape" applied to one side, and white "slide" tape applied to the other side, which makes the wedge even thicker than it appears in the photo, which means that in practice the end of wedge is even more truncated. So I have a hard time supporting my knives accurately on this wedge while sliding them down into contact with my stones. Prior to buying this wedge I just used a wooden wedge I cut off of a 3" by 3" post using a miter saw, said wedgewhich has a much less truncated end. That wooden wedge unfortunately absorbs water from my Japanese Waterstones. But I will try spraying polyurethane on that wooden wedge to help waterproof itand try again. If that doesn't work I will try to find a 3" by 3" plastic trim board somewhere and cut a wedge off the end of that. Note that you can buy 20 degree plastic wedges, but this is the first one I have found that does 15 degrees (nominal.) Note that Amazon also has the Blue AngleGuide set of wedges, but they are very small https://www.amazon.com/Angle-Guides-Sharpening-Knife-Stone/dp/B01N4QMO7U/ref=sr_1_4?ie=UTF8&qid=1499301705&sr=8-4&keywords=sharpening+angle+guide
If your knife is dull, we advise you to start with the diamond stone. After restoring the edge to original shape, de-burr the edge lightly with the ceramic stone in order to get a razor-sharp edge. Use no oil or water. Start by laying the blade flat on the stone, raise the blade spine approx. the thickness of the blade, and start moving the knife in circular motions.
Speaking of building muscle memory, here is a good exercise for you, a confidence builder: Paint the edge of your knife and bevel with a Sharpie and sharpen the knife at an angle that results in the removal of that Sharpie. In many cases it will be close to the 20 deg angle anyway. When you have achieved success, repeat the process and do that ten times. Now flip the blade over and do it on the other side, you don’t need to use much pressure here, just a little. You want to get to the point where you can place the knife at the SRA “Sharpie Removal Angle” the first time, every time.
However, because the Belgian Blue stone generally occurs in relatively wide columns with much thinner layers of Vielsalm Coticule on either side adjacent to the slate, the Belgian Blue stone is more plentiful that Coticule and thus, it’s somewhat less expensive. But, it’s also somewhat softer than Coticule and is not divided into different grades as Coticule is. Furthermore, because it is a softer stone than Coticule, it is sold without a substrate layer.