Why We’ve Been Sharpening Our Knives All Wrong
Tips, techniques, and whether we should listen to TikTok hacks.
When Evan Atwell was working at a food market in the Mission District of San Francisco, he would spend his lunch breaks looking at knives. Just down the street from the Bi-Right where he worked is Bernal Cutlery, a pioneering knife shop that opened in 2005.
“I thought it was the coolest thing I’ve ever seen,” Atwell remembers. “Every square inch of the wall was utilizing display knives.”
So when he decided to open his own business in Portland, Maine, in 2018, he knew just the place he wanted to model it after. “Like all broke millennials, we started in a repurposed shipping container,” he remembers. “I spent thousands of hours scouring the internet and reading every book I could. You can just want a knife to cut stuff, and that’s great. But if you get really involved, it becomes anthropological and scientific.”
The result of all of his research is his shop Strata, which focuses largely on importing the best kitchen knives, cookware, and accessories from all over the world. Named for the different levels in Japanese knife sharpening whetstones, Strata is now in a bigger location and offers a vast (largely Japanese) collection of knives and sharpening services.
From owning his shop, Atwell has learned that “99% of people have never experienced a good knife” and he’s made it his mission to change that. Here, he shares his best tips and techniques to maintain sharp knives.
Why is a sharp knife so important?
While it might sound obvious, keeping a knife sharp can directly affect the texture and even flavor of the food you eat. Take high-end sushi restaurants, for example, which use single-bevel knives to yield very sharp edges. “They microscopically cause very little damage to cellular walls of fish,” Atwell says. “A clean, sharp cut makes the fish look like glass.”
For the home cook, a sharp knife makes a huge difference when it comes to butchery, and also cutting things like yams, which will split and crack if you use a dull, thick knife while prepping.
“A lot of people don’t like cooking because they’re using inferior tools,” Atwell says. “A good, sharp knife can take you from hating cooking to throwing parties.”
What are the best tools to sharpen a knife?
Many of us laymen are familiar with the rods that come with knife blocks, jigs, or pull-through mechanisms, but Atwell tends to advise against using any of them.
“Honestly, I wouldn’t suggest buying anything other than whetstones or specialized machines,” he says. “These pull-through jigs and multi-rod setups are all crap.”
A lot of these tools, he says, have resulted in bent or twisted knives being brought into his shop, and a lot of consumer sharpener jigs cause more damage over time. Instead, Atwell suggests buying a whetstone starter kit. “You don’t need to spend hundreds of dollars, you don’t need 20 of them. A starter kit gives you everything you need and it lasts for years,” he says.

How can I learn to sharpen a knife?
As with any topic you want to master, the internet is filled with a ton of misinformation, and Atwell spends half of his job answering emails for people who have questions. “There are YouTube channels that range from simple anatomy and terminology all the way to advanced polishing and everything in between,” he says.
Some of the tutorials he suggests are from Japanese Knife Imports by OG knife expert Jon Broida in Beverly Hills, videos from aforementioned shop Bernal Cutlery, lessons from Tosho Knife Arts, and recipes and techniques from Hitohira, which is Stara’s main Japanese supplier.
Atwell also suggests the books Sharp by Josh Donald and Japanese Kitchen Knives by Hiromitsu Nozaki, which both have a ton of recipes and techniques.
Should I listen to TikTok and sharpen my knife on a coffee cup?
One of many TikTok kitchen hacks out there recommends sharpening the knife on the bottom of a coffee cup. We’ve also heard rumors the same technique can be used on the bottom of a ramekin cup in a pinch.
“Look, I’m a big DIY guy and have jerry-rigged all kinds of things,” Atwell says. “And technically you can sharpen a knife on anything harder than steel, which ceramic is. Putting it up against some ceramic with some texture or grit, sure, it could help.”
But, he cautions, no professional would ever actually suggest this as a long-term solution to keep your knives effective over time. “It’s a fun party trick, and there are some people online that swear by it,” he says. “But home users struggle with using a whetstone properly, so a ramekin won’t be much better.”
What are the knives I need in my collection and how often should I sharpen them?
Atwell says these questions vary by user, of course, but a good arsenal includes: a multi-purpose knife, a serrated or bread knife, a butcher knife, and a knife ideal for vegetable chopping (like a tomato knife or rectangular nakiri).
“There’s no right set-up for everyone because everyone eats different things,” he says. “But with these block sets, a lot of those knives go unused. I suggest getting your knives one at a time, investing more in each and getting less of them.”
Similarly, the frequency in which you should sharpen your knives totally depends. Rather than going by a specific metric, go by how the knife feels. “If anyone ever tells you every six months, that’s BS,” he says. “You’re the one using it and, if it stops working how you want it to, you have your answer. I hope this frees people up not to be so rigid.”
What’s the best way to store knives and maintain sharpness?
Atwell advises against keeping your knives in blocks, since a lot of sliding in and out isn’t good for the knife and also moisture can pool inside. He says magnetic clasps are great if you’re storing your knives in a drawer or there’s an old DIY hack of storing knives in a vase of uncooked rice, since grains do a great job of soaking up moisture.
But the best solution is a magnetic strip, which is probably why we see them so often in stores like Strata and professional kitchens.
“This makes it very easy to pull knives on and off, and it exposes the knife primarily to air, allowing acids to evaporate,” he says. “Plus, it just looks really cool.”