Application Tips
and Frequent Questions

Basically, diamonds are harder than any knife steel and therefore hardly wear out during the grinding process. However, during the first grinding processes, production related surplus diamonds are quickly removed. After the somewhat rougher grinding noise at the very beginning, the disc quickly sounds finer when grinding has reached its normal usage surface. The diamonds are set about 55% deep in a nickel bed. If this nickel bed is broken by sharp, chipped or damaged objects, diamonds might fall out. Therefore, use it only to sharpen kitchen and cooking knives. The sharpener is not suitable for scythes, scissors, garden tools, chisels or similar. Depending on the level of use, the diamond disc will not need to be replaced in an entire kitchen lifetime.

The corundum whetstones wear off visibly during grinding and with average use, they have a service life of 3 - 6 years. The #6000er corundum whetstone wears off faster than the #3000er corundum whetstone. Before and after grinding, remove any grinding dust from the sharpener, Magent-Angle-Support and knife.

It's best to clean the corundum whetstones by gently rubbing both their surfaces against each other. Just a few circular motions are enough to clean them.

To change the grinding discs, the sharpener must be held with both hands on the wheels and screwed on with an opposite screw movement. One of the two sides (either the diamond side or stainless steel honing side) always detaches first. Which disc detaches first can vary. If you only want to change one disc, unscrew the desired disc. If you want to remove both grinding discs, unscrew the detached disc completely, then remove the wheel and grip roll.Then hold the steel axle firmly with one hand while unscrewing the disc with the other hand. Depending on the amount of force required, use pliers to grip the axle more firmly. CAUTION: Washers are installed in some places between the axle and the wheels. Make sure that these are inserted in exactly the same place again when reassembling.

To find out whether the knife has already "learned" the 15°, the so-called "edding method" can be applied. First, color the top part of the blade with a felt-tip pen. Then place the knife against the angle support and grind it as usual. After a few grinding movements, you can visually check whether the coloring from the felt tip pen has already been ground away. If you can still see the color, then the knife is not ground in yet. In this case, the old grinding angle will still prevent you from hitting the cutting edge. This procedure should always be carried out on both sides.

With a little practice, the rough serrated edge on classic bread knives can be sharpened just as well with the sharpener. However, please make sure to sharpen the knife only from the side which was ground from the factory. When sharpening serrated knives without an angle support, hold the knife so that the grinding disc hits the edge. Since each serrated edge is manufactured differently, the knife must be fixed by hand here. Then turn the sharpener slightly towards the cutting edge so that the radius (the outer diamond-coated edge) of the diamond disc dips into the ridges of the bread knife. Now, always pull the sharpener from the tip of the knife towards you always in one direction only and not back and forth. Following this principle, the other side of the knife can only be deburred with the stainless steel pull-off side.

Although damascus knives are often made of harder steel than most ordinary knives, a hardness degree of beyond 60 HRC is no problem for the sharpener.You can use the sharpener to sharpen any steel knife. Due to the even application without any concentrated strain, the sharpener sharpens even the most precious knives with the highest precision. Due to the constant grinding angle, only the material that prevents the knife from becoming sharp again is removed. This is why the sharpener is not only more efficient, but also much gentler than most knife sharpening systems.

There is a great difference between the sharpener and other common knife sharpening systems. The most important difference in its application compared to sharpening block or "pull-through" device is the non-existent point load. Over time, point loading produces uneven and unsightly results and is the reason why a cutting edge is often destroyed. The smooth rolling motion of the sharpener on a firmly fixed blade allows the knife to be worked evenly with no damage being caused to the knife. Another big difference e.g. to classical waterstones / whetstones is the constant maintaining of the ideal grinding angle. Precisely by hand on the stone is a real art and very difficult. With the sharpener and the Magenetic-Angle-Support, the knife is always fixed exactly at the angle at which it was last sharpened. The result is less material removal, faster results and with no prior knowledge required.

In general, the sharpener is well suited for also sharpening ceramic knives. However, since ceramic is not magnetic, the angle must be maintained by hand.

There are different stainless steels for different applications. Some stainless steels are magnetic and some are antimagnetic. Antimagnetic stainless steel is used for things like kitchen sinks and similar items but this steel would not be suitable for hardening and certainly not for manufacturing a high-quality knife. Since every hardened steel structure is magnetic, knives also marked "stainless steel" are usually magnetic.

You do not need water to sharpen knives with the sharpener because no significant heat is generated due to the smooth rolling movements. The diamond coating is also designed just to be used dry. The additionally available high-grade corundum grinding whetstones also achieve top results when used dry.

The sharpener is primarily designed to sharpen large and small kitchen knives. Therefore, due to the possibility of a great difference in grinding angles, sharpening scissors, scythes or other tools with the sharpener is not recommended.

Cutlery knives often have fine serrations which cannot be sharpened with a sharpener. However, smooth cutlery knives can be sharpened without any problem.

The grinding angle is the angle at which the knife is machined from one side. Since most knives are ground on both sides, the grinding angle (e.g. 15°) is also ground in from both sides. After grinding both sides with 15° grinding angle, a 30° cutting edge or 30° cutting angle is obtained. Therefore, the cutting angle is usually twice the grinding angle.

For knives that have been sharpened freely by hand until now, the angle usually varies after each sharpening. For this reason, the actual grinding angle can often not be determined. Therfore, it is worthwhile to sharpen your knives once with the sharpener and the Magentic-Angle-Support to a constant grinding angle which can be reproduced with each sharpening process.

Basically, the grinding is always done from coarse to fine. The diamond disc is the most abrasive grinding disc and so it comes first in order to grind in the 15° grinding angle as quickly as possible. After grinding, the stainless steel honing side is recommended to remove any detached grinding particles or to deburr the cutting edge. If you have the #3000 & #6000 corundum discs, you can first use the #3000 grit (blue) directly after the diamond side and then use the #6000 grit (white) for the final grinding stage. Within only 1-2 minutes you will achieve a very fine grinding result. We recommend using the leatheronly after the last grinding process.

Most kitchen knife manufacturers produce a 15° grinding angle. This angle is the optimal mix of stability and sharpness. However, more important than 13°, 15°, or, for example, 18° grinding angle is its consistency and reproducibility. Only at a constant grinding angle can the material that really prevents the cutting edge from becoming sharp be removed. This means that with a reproducible grinding angle only minimal material is removed and the most gentle processing of the blade. This is why, as a rule, 15° is recommended.

If there are grinding dust deposits on the diamond grinding side after a few grinding operations, these can be cleaned with an eraser. Coarser particles can be easily removed with a damp dishwashing brush and a little washing-up liquid. For very stubborn dirt, soak the diamond disc in a hot water bath. Then remove the dirt with a little detergent and a brush.

In order to sharpen more unusual blade heights, such as cleavers, which are higher than the sharpener's grinding disc, the sharpener is supported accordingly during the grinding process, for example with a cutting board. The sharpener is then moved to this height, while the knife is attached to the Magnetic-Angle-Support on the lower surface's level.

As a rule, 1 - 5 minutes (or 10 minutes in hardness cases) of grinding time must be spent once before a knife is sharpened for the first time by the roll grinder, as the 15° grinding angle must first be taught-in. The actual grinding time may vary depending on the condition of the blade. Resharpening usually requires only a few movements from both sides due to the constant grinding angle.