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Diamond Machining Technology (DMT)
(The Benchmark for Diamond Sharpeners)

For over thirty years, DMT has been the leader in, and innovator of, a full range of diamond sharpening products that are dependable and solve a multitude of sharpening, honing or de-burring needs. DMT’s patented and award-winning products are known for their superior quality and versatility, are easy to use and allow for sharpening in a fraction of the time required by other methods. DMT products are popular with woodworkers, chefs and gardeners, in the kitchen, workshop or tool room, or to take camping, hiking, skiing, hunting and fishing.

DMT Diamond Sharpeners are an excellent value because of their durable construction, quality and reputation for providing years of uncompromising service. Unlike conventional oilstones, Japanese Water Stones, Arkansas stones and other ceramic sharpeners, DMT Diamond Whetstones will not break, chip, crack, hollow or groove. Do not be fooled by other diamond sharpeners made in other countries who claim their products are just as good — If you want the best care for your edge, demand DMT!

When compared with conventional sharpening stones, all DMT products work faster and sharpen exceedingly quick using light pressure – and they remain flat! It is important to note that all DMT diamond products are manufactured to the same high standard using the same high-quality monocrystalline diamond that makes sharpening with DMT superior.

Why Diamond?

If you look at the “Vickers Hardness Scale” picture (Above), you will see that Diamond, which is the hardest material, known to mankind, is given 10,000 on this scale. The nearest competitive abrasive material to diamond, Cubic Boron Nitride CBN), is around 4,000 on the Vickers Hardness Scale, which means that diamond is some 2.5 times harder than this material. Another abrasive is Aluminium Oxide (Al2O3), common used in Ceramic Sharpening Stones, is about 2,500 on the Vickers Hardness Scale, but even this extremely hard material is still 4 times softer than diamond. So you can see that diamonds are not just a girl’s best friend, they are the best buddy to anyone who wishes to sharpen steel or tungsten tools. Anyone who use the amazing Ceramic knives, will see DMT Diamond Whetstones as a real godsend, they will quickly and easily sharpen these super hard blades; diamond being 4 times harder that the Aluminium Oxide that makes them.

Types of Diamond

DMT Diamond Whetstones are renowned for their remarkable sharpening speed. The sharpening speed of DMT products is a function of the quality of the micronized super abrasive, monocrystalline Diamond. The “Types of Diamonds”, picture shown above, demonstrates the view of monocrystalline Diamond Crystals vs. Polycrystalline Diamond Crystals.

Mono and Poly

Monocrystalline Diamond
(A Strong, Single Crystal)

DMT uses Monocrystalline Diamonds, which are single crystalline diamonds that are incredibly strong and do not break apart with use. The diamonds are uniform and precisely sized Monocrystalline Diamonds that are permanently bonded to nickel on a precision ground plate. Approximately two thirds of each crystal is embedded in the nickel with one third exposed. Because Diamonds are the hardest material known, the working abrasive points (top third of the diamond) will wear very slowly to give a long product life. Extremely pure, DMT diamond crystals permit a single layer of diamond to perform for years.

Polycrystalline Diamond (Weak diamonds that easily fragment)

DMT competitors use Polycrystalline diamond; this fragmented compound easily breaks apart, quickly and easily wears away, and will, therefore, be easily ground down with minimal use. Some competitor’s claims of multiple layers of diamond only indicate poor quality diamonds that, again, will quickly wear out and need replacement.

Diamond Grits

By working through the DMT system of progressively finer grits, you will quickly achieve a razor sharp edge on quality knives and tools.

Q: So Which Grit Should I Use?
A: Which grit you should use depends on. Ask yourself these questions and then read the grit descriptions below to determine which grit(s) best suits your needs.

  • How often do you sharpen?
  • How dull do you let your knife or tool edge get before you re-sharpen it?
  • How sharp is sharp enough for you?

The DMT diamond products are colour-coded for identification. This is a list of the colour code and grit /mesh size:

Extra-Extra Coarse (XX) Silver - 120 microns 120 Grit. The Extra-Extra Coarse is used when serious stock removal, in the fastest possible time, is required. It is ideal for the quick repair of nicked, chipped or otherwise damaged blades or for when a bevel angle needs to be changed. It is great for flattening other types of sharpening stones such as Japanese Water Stones or India Oilstones. Colour code: Silver

Extra Course (X) Black - 60 Microns - 220 Grit/Mesh: - Recommended for aggressive removal of metal on damaged tools, or for heavy-duty outdoor tools such as axes and lawn mower blades. This grit is great for flattening Japanese Water Stones and is also commonly used as the first step in flattening the backs of chisels and plane irons and for rapid stock removal from a chipped or badly damaged edge. Sharpens garden tools, axes, lawnmowers and flattens Japanese Water Stones. Colour code: black

Course (C) Blue - 45 Microns - 325 Grit/Mesh: - Rapidly hones and restores dull edges on neglected tools, blade and general cutting tools bringing them back to a sharp cutting edge again. Customers that desire fast action cutting, without worry of edge refinement, often use our coarse models. Colour code: Blue

Fine (F)Red - 25 Microns - 600 Grit/Mesh: - Ideal for putting a razor sharp edge on a blade that is regularly maintained. Restores to a fine edge any knife or tool that is slightly dull. Many of our customers consider the fine grit to be a medium/all purpose sharpener. Professional Chefs and gourmet cooks prefer using our fine grit models. For woodworkers and sportsman who are stepping through the grits, it’s the edge refinement step done before micro bevelling and polishing. Colour code: Red

Extra Fine (E) Green - 9 Microns - 1,200 Grit/Mesh: - Polishes and refines the edge, to razor sharp perfection, of knives and precision tools after they have been sharpened on a coarser grit stone. If you are new to sharpening or if you do not need your knife or tool edge to be as sharp as absolutely possible, this grit is not recommended, however, if it’s not sharp until it’s sharp enough for you, this is the grit you are looking for! Colour code: Green

Extra-Extra Fine (EE)Tan - 3 Microns - 8000 Grit/Mesh: - The Extra-Extra Fine stone provides the finest polished edge of all of the bonded diamond abrasives. This stone is used to create a mirror finish to a cutting edge after sharpening has been done of a coarser stone. Colour code: Tan

DMT Construction

Picture showing how
DMT Diamond Whetstones
are constructed
  • A sea of diamonds bonded in nickel to the steel base plate.
  • Recessed dots provide chip/swarf clearance to prevent loading and speed sharpening.
  • Sharpening surface is lapped flat and supported by a reinforced polymer.

Easy Care & Usage

DMT Diamond Whetstones are precision tools. When used with reasonable care, they will give many years of faithful service.

Breaking in Period

Initially your diamond stone will seem especially rough. It will smooth over time with gentle stroking without impacting performance. You need not exert extra pressure - let the diamonds do the work!

Using a Diamond Whetstone

  1. Use only light pressure when sharpening. As a rule, 5-10 minutes on a conventional oilstone is equal to about 20 seconds on DMT Diamond Sharpeners.
  2. Use only water as a lubricant. A lubricant is only necessary to speed the process of clearing swarf (material removed during sharpening) into the recessed dots.

Care of a Diamond Whetstone

After use, rinse and dry your diamond sharpener. Store dry. When further cleaning is needed, use an abrasive cleaner (non-petroleum base) and a scrub brush. Always store your diamond sharpener clean and dry or the metal fines removed during sharpening will rust if left on the surface.

DMT Diamond Sharpeners are an excellent value because of their durable construction, quality and reputation for providing years of uncompromising service. Unlike conventional oilstones, Japanese Water Stones, Arkansas stones and other ceramic sharpeners, DMT Diamond Whetstones will not break, chip, crack, hollow or groove. Do not be fooled by other diamond sharpeners made in other countries who claim their products are just as good — If you want the best care for your edge, demand DMT!


The DMT Commitment - For over a quarter century, DMT has been committed to one thing - to innovate and produce the world's finest diamond knife and tool sharpeners. All DMT products are made using the highest quality materials and workmanship and are guaranteed to be free of defects. Any products found to be defective will be replaced free of charge - it's that simple!

DMT Coarse Grit (Blue) vs. Competitor's Coarse Grit

Q: What makes a sharp edge?
A: A smooth, consistent bevel after sharpening!

DMT Sharpened Edge

Major Competitor'sSharpened Edge

An experiment was conducted to measure the results obtained when sharpening a bevel edge with both DMT diamond and a major competitor's diamond guided sharpening systems. All diamond sizes from both DMT and competitor were tested under equal conditions and then photographed at equal magnifications, looking directly into the cutting edge bevel. Measurements were taken from the actual photographs of the edge; the narrower (smaller) the bevel width, the sharper the edge. The photographs are testimonial to the actual width and surface finish of the cutting edges achieved when sharpening using comparable grit sizes from each manufacturer. Clearly, with DMT, the Diamond Gives the Edge.

DMT and the Outdoor Enthusiast

Enthusiasts worldwide prefer DMT's award winning products to care for their edges. Just as essential as your pocketknife, DMT Diamond Sharpeners are lightweight, easy to carry and durable. They withstand harsh environments and sharpen all kinds of knives, tools and edged equipment that hunters, hikers, rock climbers, adventurers, campers and sportsman rely on to survive and enjoy the outdoors.

  • DMT products sharpen knives much faster and easier than conventional sharpeners. For example, sharpening a knife with a typical oilstone becomes a real chore taking anywhere from 5 to 15 minutes and requires messy, smelly oil. That same "chore" takes less than 1 minute using a DMT Diamond Whetstone of equivalent grit AND no oil is needed. All DMT products can be used with water only or dry. They will never dish, hollow, groove, chip or break and are your pocketknife's perfect companion.
  • Out in the field, or back at camp, DMT products like the DuoSharp, or the Diamond Serrated and Straight Edge Knife Sharpeners, Mini-Sharp Sharpeners and Aligner are an outdoor essential.
  • In addition to sharpening hunting and pocketknives, DMT products are popular for sharpening a wide range of household knives and tools such as kitchen knives, pruning shears, axes, scissors, chisels, router bits, utility blades etc.

DMT in the Kitchen

DMT Diamond Sharpeners will quickly sharpen the toughest stainless steel kitchen cutlery while removing a minimum of material from the blade - unlike electric sharpeners. Manual sharpening with DMT products is fast, easy and versatile. Whether you have a common chef's knife, a Japanese Sashimi knife or even a steep-angled meat cleaver, DMT can do it all.

Traditional Butcher steels do not remove much metal because they are about as hard as the knife. Butcher steels only align the edge. Since they remove very little metal, they round the shoulders of the blade. This diminishes the life of the knife.

Each time you sharpen on a Diamond Steel, a very small amount of steel is removed keeping the edge of the knife thin and the angle maintained. The diamond, or unbreakable Ceramic Steel extends the life of knives, this alone can pay for the cost of the DMT sharpener.

Many chefs and home cooks prefer to use a Diamond Whetstone to sharpen their favourite knife. A few light strokes are all that is needed. You can use a Whetstone to sharpen when you need to re-align an edge or just because you prefer to use a Whetstone. Having a Diamond Whetstone in the kitchen doesn't mean that you can't also use it to sharpen other edged tools that you may have in your home – scissors, woodworking tools, and more. It's a great value and a lot of sharpening potential from just one sharpener.

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