Whetstone sharpener or sharpening stone has been here and there for a long time even before we born in the form of natural stone whatever they look like. Until today, the natural stone likely to be the most preferred options to sharpening things because of their versatility. As the technology improves, there are immerging new models and we are now not only having an option to the natural stone, but there are also other types considered better and more practical to use. The arrays can be bewildering to the inexperienced sharpeners that so often times many of them end up with a crap or wrong decision on stone type for their utensils.
Most people don't think about sharpening knives until this vital kitchen tool is no longer sharp. The truth is that nothing impacts the longevity of your knives, or their daily performance, more than regular sharpening and maintenance. A dull knife in the kitchen is more dangerous than a sharp one when employees must force their way through cutting meat and slicing vegetables. As a result, daily sharpening and maintenance is easy, and most importantly, necessary. We're here to show you how to use a sharpening stone, including correct techniques and maintenance. The end result is a more efficient, and safer, set of knives!

With its premium series Select II, the whetstone manufacturer Sigma Power Corporation from Tokyo addresses users of high-alloy steels such as HSS. These stones, too, are obviously intended to engender a grinding experience similar to that of natural stones. The special production process is expensive, but the Sigma Select II probably has no equal when it comes to demolishing steel.

A common myth is that sharpening steels actually sharpen knives, and can replace stones or other sharpening devices. Steels actually hone a knife and help keep its edge if used regularly. A steel should be used before and after each knife use for proper maintenance. Easily enough, it's used the same way you use a sharpening stone. To find the proper angle, hold the knife horizontally with the edge touching the steel. Move the spine upward to create a 45-degree angle, and then half that again for your optimal sharpening angle.
I enjoy these stones so much that the feedback is not a deterrent at all for me, I don’t even think about it. The results are always nothing but top notch, they deliver exactly what I want, some of the sharpest knives I have ever produced were sharpened on Shapton Glass stones. They may be thinner but they last a very long time, they are easy to maintain as well,

The dual-sided whetstone is made from durable silicon carbide and has 400 grit on one side to sharpen the dullest blades and 1000 grit on the other side to create a nice smooth finish once the blade has been sharpened. The stone also forms a nice slurry that helps polish the blade for a superb shine. The stone is meant to be used with water, not oil and for best results, simply soak stone for 5-10 minutes before use, and lubricate with additional water as needed when sharpening.
I recommend keeping two stones in your kit. One with a medium grit (around 800 or so) to perform major sharpening jobs, and one with a fine grit (at least 2,000) to tune the edge to a razor-sharp finish. For real pros, a stone with an ultra-fine grit (8,000 and above) will leave a mirror-like finish on your blade, but most cooks won't notice the difference in terms of cutting ability.
Like all DMT® products, DMT sharpening stones are proudly made in the USA and will produce excellent, consistent results time after time, year after year. DMT's diamond sharpening stones feature the most diamond per square inch in the industry and a proprietary process that ensures near-perfect consistency in grit size, engineered to be the flattest sharpeners on the market. Simply put, DMT’s premium sharpening stones are best-in-class products with undeniable long-lasting value.
Actually, the company contacted me to make sure I received the stones and that I was happy with them. Excellent service. The stones are great! I'm pretty much a novice so the clear instructions that came with the stones and the eBook instructions were wonderful. The eBook had quality pictures demonstrating the use of the stones and the written instructions were clear and to the point. Within minutes of opening the box I had the stones figured out and sharpening my AF survival knife, my pocket knife and a couple of my wife's kitchen knives...which included a very expensive chef's knife. Very satisfied with this product and highly recommend it.
Functionality – If you have experience with the stick or sharpening stone you likely don’t want or need anything else. If, however, you are in search of an electric-powered sharpener you’ll want to consider how many “stages” you need in your sharpener. In a typical 3-stage sharpener the first stage is the coarsest and does most of the heavy lifting required to turn the edge from dull to sharp. The second stage will have finer grain sharpening wheels. These are used to hone the edge, that is, to smooth out the burrs left by the coarse first stage. A third stage will refine the edge even further and remove any debris left over from the sharpening process.

Ye olde tomato test - After you have sharpened using one of the above sharpeners grab a firm tomato and try to slice it. If the blade is properly sharpened it will slice through the skin with virtually no effort and without pushing the skin inward first. If the skin is able to fight back against the blade then your knives are not properly sharpened yet.
Historically, there are three broad grades of Japanese sharpening stones: the ara-to, or "rough stone", the naka-to or "middle/medium stone" and the shiage-to or "finishing stone". There is a fourth type of stone, the nagura, which is not used directly. Rather, it is used to form a cutting slurry on the shiage-to, which is often too hard to create the necessary slurry. Converting these names to absolute grit size is difficult as the classes are broad and natural stones have no inherent "grit number". As an indication, ara-to is probably (using a non-Japanese system of grading grit size) 500–1000 grit. The naka-to is probably 3000–5000 grit and the shiage-to is likely 7000–10000 grit. Current synthetic grit values range from extremely coarse, such as 120 grit, through extremely fine, such as 30,000 grit (less than half a micrometer abrasive particle size).[citation needed]

In addition, there are three broad grades of Japanese Water Stones consisting of the Ara-to (rough stone), the Naka-to (middle/medium stone) and, the Shiage-to (finishing stone). However, it should be noted that the various grades of natural Japanese Water Stones vary widely in both density and grit size from stone to stone and thus, they do not translate well to American or European abrasive standards. Furthermore, because they are significantly softer than Novaculite, Japanese Water Stones must be flattened more often and do not last as long as a either Novaculite or Coticule stones. But, because they form a slurry of fine particles when used, they also do a superior job of both cutting and polishing.
You've acquired a good chef's knife, you're using it almost daily to make tasty dinners for the family, and it's stored in a nice knife rack or a magnet for safekeeping. So why stop there? Keeping that knife's edge fine will make cooking not only safer but, let's face it, much more fun. Whether you've spent £150 on a high-end knife or under a tenner on a dinky paring knife, keeping it sharp is crucial. 
Over the course of two days I re-sharpened nearly a dozen old blades, including removing the secondary bevel on an old stainless Ontario saber-grind Navy diver's knife, convexing the edge on flat ground 1095 Schrade 55 that also came with a secondary bevel, and fixing a broken tip on an old Kershaw folder. These stones made quick work of the Schrade and Kershaw. Both had completely new edge geometry within 30 minutes apiece. The Kershaw looked like-new, as if the tip had never broken. And the Schrade cut much better than it's secondary bevel would previously allow, regardless of how sharp I got it with a ceramic rod and strops. The Ontario took a little more work, as it had been abused a little the last time I'd held it, over 25 years ago and was as dull as a case knife - one of the reasons I decided to go ahead and do a full saber grind - well, a slightly convexed saber, I suppose would be more accurate. But within under an hour of using the two stones and a couple leather strops (one with black compound, another with green), the Ontario was shaving sharp again too.

With its premium series Select II, the whetstone manufacturer Sigma Power Corporation from Tokyo addresses users of high-alloy steels such as HSS. These stones, too, are obviously intended to engender a grinding experience similar to that of natural stones. The special production process is expensive, but the Sigma Select II probably has no equal when it comes to demolishing steel.
Begin with your lower-grit stone. Place the heel of your knife on the far edge of the stone, holding the blade gently but firmly with both hands at a 15- to 20-degree angle. Using even pressure, slowly drag the knife over the stone toward you down the length of the stone while simultaneously moving the knife such that the contact point moves toward the tip of the blade.
Hobby microscope view of a 220 grit diamond sharpening stone. Tiny diamonds are electroplated to a perforated metal carrier strip and bonded to a plastic backing. The feature identified with the red line across it measures about 0.08 mm across. The dark area at upper right is a void designed to allow for swarf created during sharpening to be cleared from the diamonds. This relatively coarse stone would be used to reshape a damaged blade edge which would be refined by finer grit stones.
Once you’ve decided to start sharpening your kitchen knives with a sharpening stone, you’ll need to take the necessary steps to actually get going. These steps include finding and buying the best sharpening stone for use at home, learning the basic technique involved in doing the sharpening, and then practicing enough times to get it right. (For the sake of the knives, we don’t recommend using your best kitchen knives for practice!)