The first thing chefs often do when they buy a new knife, is to bring it to their favorite knife sharpener to have it re-sharpened. The result that they want to achieve, is a convex, sharper and smoother edge that lasts longer and is easier to maintain using a sharpening steel.

Good knife sharpeners are hard to find however. Therefore we offer 3 sharpening jobs for free to anyone who buys professional kitchen knives with us. *
You can also have your knives sharpened when you buy them, for better and longer lasting sharpness. If you want your knives sharpened by us directly, let us know by adding a note to your order. You can do this on the 'shopping-cart' page.

We recommend the upgrade to a convex edge for all plain edge knives except the knives from Global, Wabocho and Fallkniven. These already have a very thin, fine edge.

In 2003 the Dutch 'consumenten bond' (the makers of the leading consumer magazine in the Netherlands) tested professional chef's knives and found that they perform much better after a professional knife sharpener had sharpened them!

This may seem surprising, but in fact, it isn't. Sharpening a knife is a time consuming job that can only be done right by hand. The charge for sharpening an 8" chef's knife is normally between 3 € and 5 € and some knife sharpeners even ask more.

If a knife that leaves the factory would have been sharpened the same way we do it; it would be at least 10 € more expensive by the time it leaves the knife shop. Instead, to keep productions costs as low as possible, high speed belt grinders are used to produce a flat edge in no more than about 10 seconds.

The convex shape makes is possible to make a thinner - better cutting - edge without altering the sharpening angle (and therefore the strength) of the edge. You can see the difference between a factory edge and an edge that is re-sharpened by us on the picture below. The light grey shape is the cross-section of the convex edge. The dark grey shape is the original flat-gound edge.

3 Benefits

1 - Better cutting performance

It’s not only our convex shape that makes the difference; our finishing is also much smoother than the factory finishing. You can feel it when you cut your food; and you can hear it when you cut a piece of paper.

2 - Longer lasting edge

The knives that we sharpen are not only sharper; they also stay sharp longer. This is because our edge is polished and therefore less sensitive to wear and because we use a low grinding speed to prevent the edge from getting too hot.

3 - Easier to maintain

The edge of a knife is maintained on a sharpening steel. By using a sharpening steel you realign the edge on a microscopic level. The picture below shows a flat ground blade and a convex ground blade that are both held against the steel at the right angle. As you can see the convex ground blade touches the steel only near the edge while the flat ground blade touches the steel with a much wider area. If the tip of the edge is slightly worn, it doesn't touch the steel at all and using a sharpening steelwill be a hard job.
If you use a diamond coated or ceramic steel the benefits of a convex edge will be even larger. Because only the tip of the edge touches the steel very little material has to be removed from the edge to get it sharp again. From the flat ground edge much more material has to be removed to get the same result.

There are many ways to create a convex edge. The trick is to use an abrasive medium that is flexible. We have experimented with a lot of materials in our search for the grinding method that gives the best result and is also practical for commercial purposes.

We start with a medium grid to grind the edge into the right shape and then finish it with a very fine grid. All at low grinding speeds to prevent the edge from getting too hot. If the edge gets too hot (see sparks in factory production) the tip of the edge will detemper and loose part of its resistance against wear. By re-sharpening at low speed the detempered tip will be grinded away (this is only about a tenth of a millimetre) and the new tip will have optimum hardness.

After the fine grinding step, we carefully remove the burr and polish the edge on a leather belt with honing compound. This makes the edge extremely smooth for better cutting and wear resistance.