Here’s a quick Technique of the Week to get us started. You often read that you should sharpen your knife to 20° or 15° or some other seemingly arbitrary number. If you have a standard European-style (German, French or something along those lines) chef’s knife, it probably has edge angles of 20-25° per side. A western-style Japanese chef’s knife (Shun, Mac, Global, et at) will have edge angles about 15-16° per side. The trick is being able to find and repeat those angles. That’s where the Magic Angle Finder comes in. I won’t go into the math, but you can divide the height of the blade (at the heel) by a specific number to find out how high to raise the spine above the sharpening stone for a given angle. It sounds more complicated than it really is. Here’s how it works:
Chad’s Magic Angle Finder
For 20° divide by 3
For 15° divide by 4
For 12° divide by 5
For 10° divide by 6
For 8° divide by 7
So, if your chef’s knife is 1.5 inches tall, measured from spine to edge, and you want to put a 20° edge on it, just divide 1.5 by 3 to get .5 inches. Lay the knife flat on the stone and then raise the spine .5 inches. You have just set the edge angle at 20°. It works in metric, too. If you want to put a racy 12° edge angle on your Japanese gyuto and it is 45mm wide at the heel, just divide 45 by 5 to get 9. Raise the spine to 9mm above the stone and you are good to go. It can be a little tedious to sit there with a ruler, checking to make sure you’re at the right height but the payoff in consistency is well worth it. It also helps ingrain the angles into muscle memory so that the next time is much easier.
Coin Tricks
If that is too nerdy for you, you can just use a stack of quarters. A US quarter coin is officially .069 inches thick, though they vary slightly. Four quarters is a little more than .25″, five quarters is about .33″, six quarters is about .4″, 7 quarters is just under .5″ and eight quarters is just over .5″. It takes a surprising 15 quarters to reach a full inch high.
To raise the spine of your chef’s knife .5″, use 7 quarters. It’s not quite .5″ but the width of the spine makes up the difference and puts the spine at almost exactly the right height.
I own several Shun knives and the manufacture recommended angle to sharpen and hone is at 20 degrees…..Just thought you might like to know that for future reference.
P.S. i do infact sharpen mine at 15 degrees and usually hone at about the same angle.
[...] custom makers, and there are a few reasons for this. quick and dirty, and not 100% accurate. Knife sharpening: Coin Trick & Magic Angle Finder | An Edge in the Kitchen the only 100% accurate way is to use a sharpener like the sharpmaker and do it on your favorite [...]
Correction on the Shun sharpening angle, according to their web site:
Correction to Chef Tim on the Shun sharpening angle. Chad got it right in the article, though. According to their web site:
“Shun knives are sharpened to a 16° angle on either side.”
– http://www.kershawknives.com/faq.php?brand=shun
And if you can be without it for up to four weeks, they’ll sharpen it and send it back to you for free (that also goes for warrantee service). You have to get it to them on your dime, though.
Stephen.
If you are the guy who wrote a 2003 article, Knife Maintenance and Sharpening, on eG Forum, I am impressed. You must be very smart, because you stated some things I was thinking, but no one seemed to believe. (Just kidding, but I did feel less stupid.)
I just could not get a sharp edge. Now, I am optimistic. My cutting is 95% skinning, gutting, and a little boning. It has always seemed that a burred edge worked best. Does that make sense?
It never occurred to me to make the two angles in the edge.
Question: for my uses: gutting and skinning, which angles are best?
BTW, my Father could do the fancy steel thing, but he drew the edge away from the steel, in a strpping fashion. He said it was safer, and drew out the burrs.
Last question? Do you recommend, when using a Lansky, to sharpen part of the blade, then move the blade down in the clamp, to avoid rounding the edge?
Thanks. Riecke