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.
Good for a quick touch up: As I mentioned, I think there is a case for owning both a manual and an electric knife sharpener. This is the use case I was talking about. Manual sharpeners are great for a quick touch up to your knives in between full sharpenings with the electric sharpener. You can even take them with you camping or to a vacation home to keep your knives fresh while you’re away from home.
HIGH-QUALITY DOUBLE-SIDED KNIFE SHARPENING STONE: Coarse side 1000 grit leaves metal edge with frosted appearance. Edge sharpness equivalent to majority of factory edges on knives, tools; Fine side 4000 grit is ideal for finishing and polishing the edge, make edge very sharp, and edge reflects light well. Perfect for light touch-ups to an already sharp.

One of the most well-regarded natural whetstones is the yellow-gray "Belgian Coticule", which has been legendary for the edge it can give to blades since Roman times, and has been quarried for centuries from the Ardennes. The slightly coarser and more plentiful "Belgian Blue" whetstone is found naturally with the yellow coticule in adjacent strata; hence two-sided whetstones are available, with a naturally occurring seam between the yellow and blue layers. These are highly prized for their natural elegance and beauty, and for providing both a fast-cutting surface for establishing a bevel and a finer surface for refining it. This stone is considered one of the finest for sharpening straight razors.[citation needed]
Though "whetstone" is often mistaken as a reference to the water sometimes used to lubricate such stones, the term is based on the word "whet", which means to sharpen a blade,[1][2] not on the word "wet". The verb nowadays usually used to describe the process of using a sharpening stone is to sharpen, but the older term to whet is still sometimes used. The term to stone is so rare in this sense that it is no longer mentioned in for example the Oxford Living Dictionaries.[3][4] One of the most common mistaken idioms in English involves the phrase "to whet your appetite", too often mistakenly written as "to wet". But to "whet" quite appropriately means "to sharpen" one's appetite, not to douse it with water.
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.
Certain knife sharpeners require you to spend up to 15 minutes of your life, just to get the edge or sharpness that you desire. If you are a busy individual, you may not have all that time in your life, and that is where the SunrisePro Knife Sharpener comes in. It makes the whole process of sharpening a knife easy and fast. It doesn’t matter how dull or damaged your blade is, this machine gets the job done within a few seconds.
For woodworking tools like chisels and plane blades, you will need stones that are at least as wide as the blades themselves. Length is helpful but not always critically important. The one exception is when you're using a guide for sharpening tools. The guide often rides on the stone and longer stones permit you to use a much larger portion of the stone as both the guide and the edge need to simultaneously touch the stones.

If you have invested your hard-earned money in a quality set of kitchen knives it is important that you care for them properly. Of course, you could always send them away for sharpening, but why pay money to have someone else do what you could easily do yourself? Not to mention the inconvenience of having to drive them to and from the sharpener or pay shipping and handling to send them by mail.
Furthermore, Novaculite consists of several different layers of stone of different densities, grit sizes, and colors. Thus, the red Novaculite layer (aka Washita Stone) is the both the softest and most coarse while, the next most coarse/hard grade is the grey/white Soft Arkansas stone; both of which cut relatively fast for a hard whetstone material and thus, they are an excellent choice for refining a bevel. Then, the next grade of coarseness/hardness is the hard Arkansas stone which is used to polish the bevel rather than define it and, last there are the grades of Hard Black and Hard Translucent Arkansas stones which are used for extremely fine honing and polishing of a cutting edge. Plus, it’s also the primary material in “Charnley Forest” (English) and “Turkey” oilstones.
As Mal Knives shows in a review, the Chef's Choice sharpener creates a triple bevel on the blade, which allows it to work with both Asian and European/American knives. The bevels are at roughly 25 degrees, 20 degrees, and 15 degrees. This triple bevel design increases the length of time required between sharpenings. However, one Amazon customer reviewer disliked the sharpening results on Asian knives with this machine.
This set of two Norton combination waterstones provides four grits and also includes a flattening stone as an added value. The 220, 1000, 4000 and 8000 grit sides will handle everything from aggressive shaping to final polishing. They are 8" long by 3" wide, big enough to handle most knives and tools easily. Our most popular waterstone kit, this has everything you need to both sharpen with waterstones and maintain the stones themselves. A great starter set.