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Food & Wine Ground >> Get a Sharp Knife for Under $5


7/31/08 12:34 AM
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crescentwrench
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Edited: 07/31/08 12:40 AM
Member Since: 1/1/01
Posts: 21770
 
 I have a setup to keep all my knives pretty much retarded sharp. It's a few stones, guides, strops, steels, polishes etc and I've spent a good bit of money and time gathering this all up. But I was looking at the ol' youtubes and seeing talk of a different way to get a knife sharp and all for next to nothing. So I thought I'd give it a go and decided to let you all know how it went.

I wasn't about to risk a good knife so I pulled out an old POS that was in my grandmother's storeroom.




It's a cleaver from back when my granddad owned a store and has this on it

Stoney Jackson
"Remember Me, I'll Be Back"
THS Vernon Company
American (Illegible)


And it's a true piece of shit, tiny with only a half tang and two rivets. But what do you expect from a promotional item? It's carbon steel so it will probably wind up holding a decent edge. Speaking of

 


yeah, that's the edge. I think it must have been used to cut bricks. The edge is about half the thickness of the spine.


 
It's not cutting anything, this is going to take some work.

So now we're on to the big bad setup. Here it is.



 
Yup, that's about it. It's just a piece of sandpaper. I got a 3 grit multi-pack for like Tree-Fitty. This one is the coarsest, 220 grit because I'm going to be taking off lots and lots of metal. You just take something with a little give, like an old mouse pad or felt or whatever, I'm using a couple of squares of corkboard that my wife got a while back. I glued them together to make them thick enough for the pushpins in the corners to keep the paper on. Then I set it on my TV tray, that's all there is to it.  The idea is to draw the knife across the paper, with the backing causing it to sink down just a fraction. This will give your edge a sloped convex edge. Sometimes called a bullet edge or apple seed. It supposedly makes for a longer lasting edge because more metal is behind it. Anyway.


 

 

 

You want to keep your angle pretty shallow, let the material work for you. Since I have a cleaver I want a pretty obtuse grind so this angle is even a bit steeper than I would probably use on a regular knife. Hell, I might lay my paring knife down completely flush on the paper.

Unlike stones, where you move edge forward to "shave" the stone, you're going spine first pulling away from the edge. Also, unlike stones I don't see any reason to use water or oil, even though my sandpaper is wet/dry. The reason for the "wet" in wetstones is to remove flakes of metal out of the way so it doesn't dull your edge on the next pass. But since we're going the other way I don't think it matters. So here we go with reprofiling. I'm going to get that flat dull edge and turn it into something resembling a knife by grinding out all that metal.

...........

..........

And here we are 2 AND A HALF BUTTFUCKING HOURS LATER!!! Holy dull, reprofiling took forever. I'll never do this again without power tools. But if your knife isn't 50 years old then it should only take you maybe 5 minutes. I had to use a good bit of pressure since this was so far gone, but on an average knife you shouldn't need much more pressure than it takes to keep the knife on the paper. In fact, too much pressure and you edge will dig in and the sandpaper will actually curve up and dull your knife. In any case, here's the reprofiled edge.

 

 

 And here's the burr catching glints of light. I had to grind out a shitload of nicks so I got a big fat burr. Yours won't need to be nearly this prominent.

 

Usually, if you can't exactly see it, you can check the length of your blade by gently drawing your finger perpendicular over the edge of the knife. A burr will feel like a catch, no burr will be smooth right off the edge.



(Notice I added a clamp so I wouldn't have to hold the paper down)  You want to shoot for a burr from tip to butt, up to what's called the choil. When you get that you're done with that side and it's time to switch. I switched regularly prior to getting close to a burr so my edge would stay close to the middle. Once you get a burr on that second side it's time to knock it off. With less pressure take a few passes on that other side to knock off the majority of the burr. Then alternate passes, kind of like a barber stropping his razor. Use lighter and lighter pressure until you're barely touching the paper.

 Knowing when you have a sharp knife at this stage is a little bit of an art. It will be sharp, but still feel pretty rough if you were to cut something. Right now my cleaver is rugged and about right for camping, but since I'm experimenting I'm going for more. So it's off to my higher grit, the 320. Now, before you move on, remember this. If your knife isn't pretty damn sharp after your coarsest grit, it will never be super sharp at your highest. The knife is already about as sharp as it can get, the higher grits are simply taking out the scuff marks of the lower grits. Even when we say sharper we really mean just smoother.

Okay, notice I'm only using enough pressure here to keep the whole edge touching. My finger is hardly pushing at all.

And here is the results after only like 10 draws per side. It didn't take long at all.



Not too shabby, I can carve through this junk mail with ease. This is about as sharp as most cooks need their kitchen knives. And except for getting it from "a thick spatula" to "averagely dull" shape it only took about 15 minutes, and all for less than 5 bucks. But since I'm experimenting. 

.......

.......

And here we go.
 



After 3 more grits (up to 2000) and it's shaving wispy hairs from my barely post-pubescent leg. I think I might give this technique a serious chance with a knife I actually use now.

  
7/31/08 11:42 AM
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crescentwrench
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 I can't edit or I'll pass the 8,000 character limit. 

But notice in the profile pic how there is a sweeping curve if you use your imagination a little.  A stone would give you a flat bevel, and you'd see a line.  And I just happen to catch the roughness of the burr in that pic.  I could tell when I was at the edge because the rust kept getting thinner and thinner.  When it disappeared I knew I was done.  If you want to replicate this and have a visual of if you have done a side for the proper time and angle, color the length of the blade with a sharpie.  When the line disappears at the edge and all you see is metal you're done. 
7/31/08 3:51 PM
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MikeZev
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 interesting. I'll try it on my stamped knives. the forged ones are prolly stayin on the wet stone.
7/31/08 5:07 PM
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crescentwrench
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I have been "stropping" all of my knives with a piece of 2000 grit paper on a mouse pad for a while now, just to smooth out the bevel change and to give it a bit of polish, not really doing much more than cosmetic stuff.  This is the first time I've tried to do any actual sharpening with it though.  It worked really well though I gotta say, and it's cheap balls.  Certainly an easier jumping off point than a $40 diamond stone and does a better job than those $2 wet stones you get at the Asian market. 

The main advantage I can see with this is if you have any unusually shaped knives.  My dad's boning knife has a big swail in the belly that makes that part almost impossible to sharpen on a flat stone.  This might be perfect for that. 
 
I'm trying the wife's parer as my "normal" knife experiment.  Yes she has her own knives, she's not allowed to touch mine. 
8/1/08 9:35 AM
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MikeZev
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 i'll give it a try this weekend and report back. I'm leary of trying this with my FA Porsche knives though.

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