Here’s our interview with Jon Broida, owner and sharpener at Japanese Knife Imports. Jon gives us some very interesting sharpening recommendations. We’re very excited to have him on KnifePlanet!
1. Hello Jon, Can you tell us a bit about yourself, and how you started sharpening knives?
My name is Jonathan Broida, and I’m the owner of Japanese knife imports. Before starting this business, I cook professionally in fine dining for many years, and before that I attended Colorado College, where I got a degree in Asian Studies, with a focus on Japan. I guess it was serendipitous how I ended up where I am now. I had always been interested in Japanese food, history, and culture. In fact, it was this interest that got me into cooking in the first place, and although I didn’t always cook Japanese food, I did spend some time studying traditional Japanese food in Japan. As I got more into my cooking career, I found my obsession for knives growing. Along with my obsession for Japanese knives, my interest in knife sharpening grew exponentially. I found that I was spending all my money on either knives or stones. I would buy all of these different things I was interested in, test them out, so the things I wasn’t in love with, and then buy new things. I did this for years. Similarly, with sharpening, my interest began when I started cooking professionally. The first place I ever worked at was a country club. They had a knife sharpening service that would come and sharpen everyone’s knife periodically. I had just received the new knife as a gift from my chef, and it was my prized possession. When the sharpening service came, my coworkers recommended that I pass the knife along for sharpening. When I got the knife back, I was disappointed to see how much metal had been removed and how poor of a job they had done. I decided from that moment that I would never let anyone else sharpen my knives again. I went to a nearby cooking supply store and bought the first stone that I found, which happened to be a King 1000 grit stone. I started asking everyone around me how they sharpened, started researching on YouTube, and looking for any books or other resources that might help me. When I worked in Japan, I made a specific point of asking my chef to teach me about knives and sharpening. Eventually, when I stopped looking, there was a time in my life where I wasn’t sure what I was going to do. My wife’s family and my parents got together and recommended that maybe I do something with kitchen knives, as they were all well aware of my obsession with them. Shortly thereafter, we started Japanese knife imports. In the beginning, it was just me and my wife Sara. Nowadays, we’ve grown into a slightly larger company, with a couple of awesome employees.
Since starting Japanese knife imports, I have had the opportunity to train in Japan with a number of extremely talented craftsmen. Every year since starting this business, we take a trip back to Japan, where I spend time meeting with makers (both people that we have relationships with already and new makers that we are interested in intentionally doing business with) and training in sharpening, blacksmithing, and in general the care and maintenance of Japanese kitchen knives. I also sometimes spend time with chefs in Japan, making sure that I know how to use the knives as well as sharpen and care for them. I used to believe that chefs with the best sharpeners because we use our knives all the time, but after training with professional craftsmen, I have started to see the kinds of mistakes that chefs make often. It’s difficult to become an excellent sharpener when there’s no one there to teach you well. Often times chefs learn from their chefs who learn from their chefs, and no one along the line was actually a professional sharpener. My training in Japan has really helped me understand the fundamental concepts of sharpening as well as some of the nuances of Japanese kitchen knives.
Jon and Sara, the minds behind Japanese Knife Imports.
2. Can you tell us more about the sharpening technique that you use today?
The sharpening techniques that I used today closely resemble those of my Masters in Japan. I think it’s very important for people to understand that there is no single right way to sharpen knives. Rather, there are a number of ways that work well, and each person will have to find a method that works well for him or her. I chose the method that I use currently because I have access to excellent master craftsman who specialize in the style of sharpening. Even within Japan, there are a number of styles of sharpening that you will see, so it’s important to state that my style closely resembles the Masters that I train with.
In our sharpening, we use Japanese water stones in varying grits, starting from coarse and working up to fine. The first thing that we do in our knife sharpening is assess the blade. I want to make sure that the blade is straight, look for any problem areas, damage, and understand the style of sharpening that has already been done to the blade, as well as get a better sense of the cross-sectional geometry of the blade itself. I then begin sharpening on a coarse stone. On the coarse stone, I am looking to create an edge geometry that makes sense for the knife, which might sometimes include thinning the knife. Also, this is the stone on which I form a burr. When it comes to Burr formation, it’s very important to make sure that you have achieved an even and consistent burr from heel to tip. This helps make sure that the profile of your knife is not changing significantly over time, and will help you avoid problems like a bird’s beak tip. On the subsequent stones, I’m trying to refine the scratch pattern, improve edge quality and fineness, and reduce and then remove the Burr. Because we sharpen professionally, the aesthetic finish of our sharpening is also often important to our customers. As we go through the sharpening process we try to pay attention to the aesthetics as well (i.e. kasumi finishes, mirror polishing, even and consistent scratch patterns, minimizing streaking around curves, removing high and low spots, etc.). We use both synthetic and natural stones to achieve the results that we are looking for, and tailor our edges to our customer’s preferences whenever possible. We also finish all of our knives with some kind of stropping, as the final step in the deburring and sharpening process. This can be done on a stone, a strop, or even newspaper.
I still think that it’s important to keep things simple. I try not to use too many stones as I go through my sharpening progression. Usually, I use two or three stones to achieve the results I’m looking for. I find that more than that tends to over complicate things.
3. Do you strop your knives on leather or another medium upon completion of your sharpening process and if so, why?
As I mentioned before, stropping is a necessary part of sharpening. It doesn’t mean that you have to use a leather strop or any special equipment. Stropping can be done on your stones, newspaper, leather, and a number of other substrates. Also, you can use find great abrasives like chromium oxide, diamond sprays, etc. as with sharpening, I like to keep this as simple as possible. My stropping is generally done on my finishing stone or on a simple leather strop. When our customers prefer it, I sometimes use a leather strop loaded with one micron diamond spray. Felts drops can also be helpful for deburring, but are not necessary.
Stropping absolutely improves edge quality, but it also tends to decrease toothiness. When it comes to kitchen knives, we are always looking for a balance of sharpness, refinement, and bite. Sharpening other tools might require different approaches, but the fundamental concepts are the same.
4. How do you test your knives for sharpness?
There are a number of ways that one can test for sharpness. The most common sense and best test that one can do would be to just use the knife on food and see how it does. Unfortunately, that’s not always possible in a professional sharpening environment so we use a number of other tests to give us an idea of where we stand. For example, sometimes we will slice through paper, which will give us an indication of edge refinement and also show us if there any nicks or small chips that we missed. I also used my thumbnail to test sharpness, as this gives me a good sense of what kind of bite the edge has. In Japan, many of the craftsmen that I train with use the hair on the back of their head as a test. I shave my head a little bit ago, so that’s not going to work so well for me.
I think that when it comes to testing edges, there are a lot of things that can be misinterpreted. For example, having a sharp edge doesn’t necessarily mean that it’s going to be the right edge what it is that you’re looking to do. It’s possible to create an edge that shaves hair very cleanly, and cuts even the thinnest paper with ease, but is just no good for food, as it provides little tactile feedback and fails to dig in on thick skinned items like tomatoes and bell peppers.
5. What do you think is the most important Water Stone in your lineup?
I think that this answer will be very different when it comes to professional sharpeners versus chefs and home cooks. For me, I would say that the most important stone in my lineup would be one of my coarse stones. There are a few coarse stones that I use, and I would be hard-pressed to say that one is the most important. If I had to narrow it down, I would say that my waterwheel (I have a motorized waterwheel that was made for me by some of the people that I train under in Japan…it’s a style of waterwheel, called a hiramae kaiten toishi, that is often used in knife making and sharpening in Japan) and my 800 grit vitrified diamond stone are the two things that I can’t imagine living without. Coarse stones help me speed up my sharpening, make repairs more quickly, and help me set up my bevels so that refinement on subsequent stones is faster and easier to do. They also are often used for thinning, which is an extremely important part of sharpening.
If I had to answer for what I think the most important stone is for chefs and home cooks, I would say a medium grit stone, in the 800 to 2000 grit range. This is the kind of stone that they will use for day-to-day sharpening, minor repairs, Etc. It also leaves an edge that is more than capable of dealing with all kinds of kitchen tasks, so if I just had one stone, it would probably be a medium grit. I really like our gesshin 2000 grit stone for what it’s worth.
6. What stone combination would you recommend to beginners?
I guess it really depends on whether the person plans to get into sharpening as more of a means to an end, or if it’s something that they’re going to be a little bit dorkier about. If it’s the former, I often recommend medium/fine combination stones like the King 1000/6000 stone, gesshin 1000/6000 stone, etc. if it’s the latter, I will more often than not recommend a stone set like our gesshin stone set. In addition to the stones, people will need some kind of solution for keeping their stone flat and holding it in place. These can vary from free to rather expensive. For example, a damp towel on the corner of your countertop can be used to hold your stone in place, but I tend to use a cambro with our stone bridge and a large stone holder. Likewise, for flattening, the sidewalk will work in a pinch, but I prefer the diamond flattening plates that we sell. There are a number of other options that will work as well. We have some videos on the subject in our knife sharpening playlist.
7. How do you flatten your water stones and how often do you do this?
As I mentioned above, I like to use a diamond flattening plate to keep my stones flat. When people are getting started sharpening, I recommend that they do this much more often, as it will be very helpful for them to have a very flat service on which to work. It helps out with angle consistency and minimizes potential problems relating to rounding over edges and inconsistent grinds as well as errant scratches. However, personally I try to use the stone service as evenly as possible, focusing on the corners when they are high, and constantly assessing my stone surface to make sure that the wear is relatively even. Because of this, I flatten much less often than most people. However, I noticed that when people see me not flattening as much, they assume that they can do the same. I would urge people to flatten a little bit more often until they feel much more comfortable sharpening. Check your stone for flatness every once in a while by laying something flat across it (like the side of a ruler or something similar). There was a time where I used to flatten after each sharpening session, but that time is long gone. I do keep some stones very flat for specific uses, such as uraoshi sharpening.
Here is a video we have on stone flattening:
8. Most novice sharpeners are very concerned about the sharpening angle. How do you feel about angles and their importance?
Sharpening angles are one of the most common things I am asked about. I find it’s often important to talk about them together, but let me address the sharpening angles first. In general, there is not going to be an exact angle that is correct, but rather a range of angles that works. For instance, most double bevel Japanese knives will work well with angles somewhere between 10-15 degrees per side. The closer you are to the 10-degree side of things, the sharper the knife will feel, but it will also be more fragile, brittle, and may not hold its edge as long. The closer you are to the 15-degree side of things, the more tough and durable the knife will be, though it won’t feel quite as sharp. It’s also ok to go even lower or higher than this, depending on your personal preference, though I often recommend staying within this range until you have a better understanding of how things work for you. For what it’s worth, Japanese craftsmen aren’t measuring the angles when they make or sharpen the knives either. Lastly, it’s important to keep in mind that you don’t have to always use the exact same angle. If you want your knife to feel a bit sharper, go a bit lower. If you need a more tough and durable edge, go a bit higher.
As for asymmetry, it seems that this is a rather confusing issue for many. Part of the confusion stems from the fact that many of the ways that we describe these asymmetries are gross oversimplifications. For example, the ratios like 50/50 or 60/40 don’t really describe anything of substance. Is it the ratio of the percentage of sharpening on each side? Is it a ratio of the angles on each side? In reality, it’s neither. No craftsman in Japan it’s there and measures angles or ratios. What really matters is the way that the knife cuts. The asymmetry deals with two main issues-thinness behind the edge and steering. The more asymmetrical a knife is, assuming the angles are equal, the thinner the knife is behind the edge. However, the more asymmetrical the knife is, the more likely it is to steer. It’s also important to keep in mind that the angles are not always equal. When figuring out asymmetry for any given knife, the first thing that you want to do is cut with the knife. When you cut with a knife, you want to assess whether it is steering to the right or to the left, and how easily it moves through the food. If you notice that your knife is steering to one direction or the other, you want to create more surface area on the side that it is steering towards, so that the knife cuts straight. This can be done by adjusting the angle (either more or less acute) and/or adjusting the amount of time spent sharpening on each side. If you notice that the knife is wedging in food as it goes through, this may mean that you need to sharpen at a more acute angle, or that you need to thin behind the edge. Some of this can also be dealt with through adjusting asymmetry, as previously mentioned.
I think our sharpie/magic marker video covers some of this too, and is an extremely useful tool in developing angle consistency:
9. Is it a good idea for a beginner to start sharpening using cheap knives? Would you recommend doing it?
Learning how to sharpen on inexpensive knives isn’t necessarily a bad thing, but there are some things one should be aware of when considering this is an option. Some very inexpensive knives will be made of steel that will not respond the same way that higher-end knives might on sharpening stones. This can often be frustrating for people as it is sometimes difficult to get a good edge, and burr removal can be a bit tricky as well. I like to tell our customers to start off with more basic Japanese knives, which are still very good, but a little bit more forgiving in terms of brittleness and ease of sharpening. Almost any mistake that they can make we can fix, so I would rather them just try and use us as a safety net.
10. Are you still perfecting and improving your sharpening technique today?
Of course! I think that the second that I stop trying to improve and learn will be the time that my career is over. Every year, when I go back to Japan to train under my various Masters, I’m always humbled by how much better they are than I am. Most of them are also much older than I am, and I’ve come to realize that there is no substitute for experience over time. In addition to training in Japan, I find that teaching people sharpening, which we do here at work, helps me improve my sharpening. I also find myself often speaking with other professional sharpeners, knife makers, and craftsmen about the craft of sharpening. It’s a very interesting community that we have, and I’ve been very fortunate to meet some amazing people through this work.
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I’ve been collecting knives for over 7 years. During all these years, I've collected knives from all over the world, ranging from Argentina to Myanmar. Besides knives, I'm an avid traveler and I love hunting and fishing.