A Knife in Need
April 28, 2021
A Good Friend, A Favorite Knife
My good friend, Tim, is a great cook. Visits to Tim's are always crowned with fantastic meals ranging from prime rib to homemade dumplings. Like many good cooks, Tim has a great collection of cooking utensils, pots, pans, and of course, knives. But like many good cooks, his knives are not as sharp as they could be.
While working on the night's feast on a recent visit, Tim asked me to have a look at his favorite Chinese chef's knife. In all honesty, it is not a top-quality blade. It was an inexpensive purchase, of no particular pedigree, and the steel is not the most high-end, but it is well-loved and well used. And it was not in danger of cutting anything in its current state. He asked me to sharpen it, and when he feeds me so well, how could I refuse?
A Starting Reference
To measure my progress, I tested the sharpness in its dull state so that I would have a reference point. I used the Edge On Up Industrial Tester which measures the force required to cut a piece of calibrated test media. I checked the knife at several points along the edge. I then averaged the results. I found the average sharpness to be 900 grams. While overall it was not as dull as I feared, the edge had some very noticeable bad spots that were very dull.
We use the Edge-On-Up to test knife sharpness. It measures the force required to cut a piece of certified test media. The lower the number, the sharper the edge. A butter knife is roughly 2000, a new knife is often around 300, while a razor blade can be sharpened below 100. We use this in our shop to objectively measure our results.
The Grinder Stone
The first order of business was to get the edge back into shape. As it was, there were noticeable flat spots that needed to be worked out. That meant that I had to start with a stone aggressive enough to quickly remove metal in order to reestablish a good edge shape. As it happens, we have a perfect stone for jobs like this, The Grinder Stone. This 80-grit stone is as aggressive as they get. And at 12" x 3", it has plenty of surface area for taking smooth, even strokes on any size blade.
I worked on one side of the blade until I had created a burr on the opposite side. Then I flipped the blade and worked the second side until I had formed a burr on the first side. The Grinder Stone made quick work of the job.
To refine the edge, I used the Nano-Hone 400, 1000 and 6000 water stones. I also made use of the Stone Stage, the 15" x 12" Terra Sharpening Pond to hold the stones and contain the water, as well as the NL-4 Flattening Stone to keep the stones clean and flat.
The Nano-Hone Product Line is a joy to work with. Well thought out, these stones, bases, and sharpening ponds work in concert. The stones have holes to match prongs in the base for a sure fit. Likewise, the base has holes to fit matching projections on the pond. The individual components work together to create a stable sharpening experience. The flattening stones are fast and true and leave a smooth surface on the sharpening stones.
The stones themselves are splash and go, so no soaking required, and they give nice feedback in use. A great balance of fast cutting and hard-wearing, they don't have the slippery or muddy feel that some water stones suffer from, rather, you can feel the grit working as you sharpen. They don't create much of a slurry and quickly produce a great edge.
After the Nano-Hone stones, I went back to the Edge On Up Tester to check my progress. The average reading was 297 grams, a significant improvement. To be thorough, I finished on a ceramic honing rod. This brought the average reading down to 196. That's a very respectable result for any knife and a great result for this inexpensive knife. Even more importantly, when I cut some shallots with it, I was able to cut them with ease.
It's a good feeling when I can put my sharpening experience to good use by helping a friend. My friend Tim always goes the extra mile to make us feel welcome and well-fed when we visit. Sharpening a favorite knife seems like the least I could do to pay him back.