Sharp knives make cutting and prepping ingredients faster, easier and safer, we know this. But what does a truly sharp knife look like? In this short but very illuminating video, Master Bladesmith Bob Kramer demonstrates five simple tests to tell if your knife is sharp enough. (Spoiler alert: it probably isn't.)
According to Kramer, a properly sharpened knife should be able to:
• Cut the tops off of carrots while they are being held, without the use of a cutting surface• Cut through paper
• Slice through a rolled up magazine page
• Easily slice a tomato
• Bite into the papery skin of an onion, without sliding
Kramer also demonstrates how a dull knife performs when attempting these tasks. After watching, I'm afraid most of my knives are due for a sharpening. How are you feeling about your own knives?
Related: How To Cope With Your Parents' Dull Knives
(Image: Emily Ho)
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Or you can, you know, just look at the edge of the knife. If you look at it straight on and you see lots of shiny spots, it's dull. Lots of sparkles and it's on its way to dull. When you look straight at the edge of a knife, you basically shouldn't be able to see the edge.
These are good tips!
I wish he had shown us how to hone and sharpen a knife! Maybe there's another video somewhere?
honing:
http://www.youtube.com/watch?v=MUdrRE7W0b4
stoning:
http://www.youtube.com/watch?v=lUbkPdkUDuo
Great tips. I use tomatoes and onions as my reference point, now I've got a few others to try.
wow. The rolled magazine example is to me a truly HORRIFYINGLY sharp knife. The kind that i would constantly cut myself with. A paring knife that sharp is an express ticket to the emergency room in my house.
I was afraid of knives growing up, because my mom would only have them sharpened when my grandpa came to visit every five years or so! My knives are much much sharper and it gives me a lot more confidence. The tomato and onion tests are good for me too. Now if I'm confronted with a dull knife I am almost incapacitated because I can't stand it. In a pinch with a really dull knife: hone it on the bottom of a ceramic mug or bowl and it will be sort of usable. :)
Elle.victor, I CANNOT handle dull knives either! My MIL has only terrible serrated (not for bread) knives or ones so dull they're like a butter knife. We do weekly dinners, and although my knives do need to be sharpened, when it's my turn to cook, I ALWAYS bring my own (and usually travel everywhere with one)
Five very good test for sharpess were mentioned in the video. I use some of them when I sharpen at the various Farmers Markets. Also mentioned was looking at the blade. A sharp knife will "split" the light, not reflect it.
A sharp knife is sfaer than a dull one!
One of the best ways to keep your knives sharp (especially if you have them rattling around in a drawer) is to protect them with these simple DIY knife guards. They're really easy to make and practically FREE!
Mine are scary dull and I know it. Time to get that taken care of. I will call this week to get them sharpened!