A better mousetrap.
Over a decade ago I extolled the virtues of a non-stainless chef’s knife from the home of all that is culinary, France. It is – or was, as it seems no longer available – made by Sabatier in France and has been in daily use this past decade in the home kitchen. However in the past couple of years I have noticed that I have been sharpening the blade more frequently and that seems attributable to the drop off in performance of the Chef’s Choice 130 motorized sharpener whose fine grinding wheel is about shot and whose sharpening steel has largely worn out its grooved serrations which confer the required burr to the blade to enhance cutting quality. In typical modern manner spare parts seems unavailable for the Chef’s Choice device which remains in the catalog and is now crazy expensive.
So a year or so ago I started looking at a replacement sharpener, aware in the process that American sharpeners confer a 20 degree angle whereas Japanese knives and sharpeners utilize the finer 15 degree angle. My years of using woodworking tools from the like of Makita and Panasonic have taught me that the Japanese frequently make a better, lighter product and that’s why the Shinkansen MinoSharp came on my radar. It claims to confer the Japanese-style 15 degree angle and while many will tell you that means you should also be using the thinner bladed Japanese knives, a few moments’ thought suggest that the thickness of the blade is largely irrelevant, it’s the sharpness of the cutting edge that matters. Once the cutting edge has done its job, the object it’s cutting parts ways, like Moses with that river crossing, and indeed I find that a very thick chopper cuts every bit as well as the much thinner Sabatier or the the paper thin carving/slicing knife in my collection.
The two wheel MinoSharp. Others are also available, including three wheel designs.
The Chef’s Choice 130 can barely accommodate the chopper, which I use a lot, so any replacement knife sharpener must allow the chopper to be sharpened. The Shinkansen device used no motors. A coarse (white) and a fine (pink) grinding wheel runs in a water bath, keeping the blade cool during sharpening. There’s quite a bit more to this seemingly simple design than at first meets the eye. I removed one grinding wheel, took a close-up snap and measured the included angle using a protractor. 40 degrees. But, in use the wheel is offset from the direction of the knife’s travel by a further 20 degrees. This has two purposes: first, it prevents the knife bottoming in the wheel which would destroy the edge. Instead the sides of the cutting edge ride on the sides of the wheel, and the instructions remind the user not to press hard and try to bottom the blade. Second, the offset confers the proper narrow Japanese-style included angle, for the wheels are canted 20 degrees, meaning that the subtended angle of a sharpened blade will be 40 x cosine (20) degrees, or 16 degrees. Smart!
The grinding wheel subtends and angle of 40 degrees.
The wheel offset is 20 degrees
In practice, knives sharpened in American 20 degree sharpeners have first to be adapted to the finer 15 degrees result expected here. That means a good 20 cycles, back and forth, on the coarse wheel, then no more than 8 cycles on the fine wheel and you are done. Thereafter only the fine wheel need be used unless the knife in question is extremely blunt. Water can be poured into the sharpening chamber through the slots in the clear cover, obviating wear to the cover which need not be removed. These slots ensure your knife will not bottom in the grinding wheels, so the cover must be used at all times,
A thick chopper fits just fine.
How does it measure up? My resharpening time has dropped from once a week to once every 2-3 weeks. And while replacement wheels are available for $14 (Size 222) and reputed to last a long time, at $20 for the whole device you might as well replace the whole thing, getting not one but two new grinding wheels in the bargain.
Recommended, and you will not miss the sharpening steel. The rough sides conferred by the grinding wheels do the trick just fine. The MinoSharo is ambidextrous and it should not be used with serrated knives.