Why the polished edge (for defense).

The Tourist

Moderator
I talked to another client last week while I polished a knife that could be used for defense. Like most people, he believed that "sharp was sharp" and "a rough knife rips." These are points I hear everyday.

First, a short refresher course. Unless I re-profile an edge (make it thinner like a barber's razor), I begin by ensuring the bevel is uniform. Remember, most knives are not. If you grab the first knife within your reach you will find that the bevel is wider in some points than in others. The edge is not going straight down the blank.

Once completed--and that's the hard part--I begin by using finer and finer grades of stone, paper, pastes and glaziers' glass to buff out any imperfection. I make a small minor adjustment at the end to lightly buff out any microscopic burrs or imperfections from the edge. Most stones are in the 100 to 200 grit range. I finish at 6000. And while they are pretty to look at, they are no weaker than the original poorly finished edge.

Will a rough, poorly knife cut? Of course. You've seen it yourself. Did you ever watch your no-brother-good-inlaw "saw" through a deer?

For our purposes, a defense knife has to slice--right now, no screwing around.

Here's the urban legend that got me into this thinking.

In 1958, police near San Diego thought organized crime was trying to muscle onto the docks. One morning a cut up body shows up, which they transport to the area coroner. This coroner takes a short glance at the body, and decisively states that the mafia had nothing whatsoever to do with the thug's death.

The officer seems surprised, and asks the coroner about his comment, to which the ME responds, "It was the Yakuza who killed this man. Look at the precision of the slices. You can't get a knife sharpened like that in the United States..."

Coupled with this, many of our modernknives are made from alloys that must be mirror finished. For example, S30V will show micro-chips on the edge (it looks like a tiny string of pearls) unless it is buffed. The alloy VG-10 is great stuff, but a simple buffing will immediately enhance its edge.

Many times here (and in Wisconsin) we cannot carry a firearm. We must decide on contact weapons, be that pepper spray, a kubaton, or a knife.

Other than a cavalry sword deliberately blunt to break bones, close quaters knives are razor sharp and have needle points. For example, the first third of an Emerson CQC-7 is a modern rendition of a Japanese lance.

While I'm not a big fan of many of the Cold Steel products, their tanto series reflects this process. Mirror finish, solid point for thrusting.

History lesson over. I'm an older guy. I probably cannot take the beatings I once endured for the privilege of a cool drink and a hotter companion. Because of professional connections, I can buy, modify, polish and carry any knife made on this planet. My defense knife has a mirror finish.

We put our best ammuntion into our CCW pistols. I advise my clients to think about that same idea with contact weapons.
 
Very good stuff from the OP. Kudos to "The Tourist." I like the Gerber Mark II myself (got one over ten years ago), though I heard they don't make them anymore- probably from some lawsuit BS no doubt.
 
like the Gerber Mark II myself (got one over ten years ago), though I heard they don't make them anymore- probably from some lawsuit BS no doubt.
Gerber Cutlery was sold to Sandvik (European maker of cutlery and cheap scissors) many years ago, and their knives look like it.

Tourist, in many of your statements, I will agree with you. I keep my knives stoned and steeled, and just touching the edge will cut you. Painlessly, but you will still bleed. I learned to sharpen knives in a meat packing plant, and if any of your friends and readers really want to learn to sharpen a knife, I would recommend they spend a few years in a packing house to learn the art.

Yes, a SD knife must cut immediately and cleanly. Most modern knifemaking steels are not fine-grained enough, a must for a surgically sharp knife. 440 stainless is one of the worst steels to make a knife out of (coarse crystals make its edge blunt) if you need a very sharp edge. Since most knifemakers started using it in the 1970s, most knife-buyers nowadays don't know what it's like to cut with a carbon steel blade. My favorite knifemaking steel is O1 or 1096, followed closely by D2. I don't care for V10, Talonite, AUS6, or many of the other sophisticated steels. I just like a knife that cuts.
 
Man I wish I could get the knack of sharpening a knife down pat. I can get them pretty sharp but never "shaving sharp".
 
I can get them pretty sharp but never "shaving sharp".

I just recently acquired some stones, did a bit of reading and started sharpening some knives. I'm starting with some of our kitchen knives. Of the five or six I've sharpened, only one will shave my arm. But I now know I can do it, but it's a matter of developing technique and consistency.

Personally, I think if it will shave you, it's good 'nuf. Polishing is aesthetically pleasing and probably contributes to a slightly sharper and longer lasting edge, but if it will shave you, I don't think you or the BG will know if it's polished or not.
 
I wasn't aware that Gerber had been sold. Plus, saying I got it ten plus years ago isn't the whole story. I should have clarified where I got it. Take it away Paul Harvey... with the REST of the story:
Mine used to be my dad's knife. He got it sometime before late 1973- I don't really know when, but I KNOW he had it in 1973 b/c I saw it in a photo with his "then brand new" 1974 Chevy truck. I've got a nasty scar on my chin from when we wrecked it in 1978. I'll never forget that truck... everyday when I shave, I've got a 1 1/2" reminder. ;)
When I first came in the Corps, I used to see the Mark II for sale at the base exchange. My dad carried his around back at home so I recognized it. I was home on leave, mentioned seeing a "new" one to my dad, and he gave it to me. I've had it ever since, though I haven't seen a "new" one in years. Did it get dropped when Gerber was sold, or was it phased out before that?
 
I thought I was the only one who still carried a Gerber knife.
Nope :)

Here's three of mine I've used over the years and still have.

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I've had a MKII since the 70's and have a pair now.

The MKI and Guardian are also from the 70's.
 
My two cents:
High carbon steel is wonderful for knives. 440C (not A or B) is also an excellent steel. Unfortunately, there are zillions of Asian- made junk knives marked "440" or "440 C" that are 420 series (or worse) steel. Few US factories ever used 440 C.
Even bad steel can make a good knife. The way it is ground makes all the difference. A properly ground blade should be thin at the edge.
The proper term is "rebevel," not "reprofile."
Benchmade folders are very good knives for the most part.
 
Bill DeShivs said:
The proper term is "rebevel," not "reprofile."

You are absolutely right about definitions. The problem is with us tinkers, we needed a word to describe the work we are doing.

First, a tinker is not a sharpener nor is he a polisher. A polisher is a highly trained artisan that refurbishes, sharpens and brings out the color of a samurai sword. A sharpener does simply that, sharpen. A tinker is a sharperner who makes small repairs to knives, handles, clasps, pots and pans, etc.

Now for the problem that Bill points to. If a bevel has been completely damaged, it needs a new bevel. If as a tinker I make a new one to factory standards, I have re-beveled the knife.

The issue is what do you call it if I set a new angle? Since it is thinner or thicker than standard, it does not have the same cutting geometry or view from the point. It has a new profile. So one tinker tells another, "I made fifty bucks on a Schrade re-profile..."

The other guy knows what I did.

(We have the same issue with glass. I'm older, so I was taught that it is called "glaziers' glass." I have come to find out it is now known as "thick glass.")

Another thing where I agree with Bill is the metal/alloy. Metal is metal, but hands down the biggest contribution is the heat treat. There, I am a snob. A craftsman named Paul Bos does my knives, or they never see my pocket.

I don't own a functioning lightsaber, but I do have a Razel crafted by the Graham Brothers (in my case, Josh Graham), made of S30V and a heat treat by Mr. Bos. I gave it a "quick buff," you know, just something to cut carrots, open the mail, slice a UPS box or overthrow a shogun.

If you follow "Keeping Sharp" over at KF (Oh, and TSR, that's a 'knife forum' no a chicken place...) you will find that there are tinkers spread all over the USA and parts of Canada. As little as twenty years ago you'd have been hard pressed to find an American sharpener who commercially used Japanese waterstones.

Go to an ATM, get a good thick stack of twenties (no, better make it fifties) and go find a tinker in your town. Follow the line of broken hearts, sick jokes, Harley burn outs and puddles of swarf.

If this hoodlum yells for you to go away, shake the money. If he gets really ornery and still tells you to go away, you've found a good tinker. Buy him a goodly tumbler of Don Julio, sit back to enjoy, see your reflection on the bevel and learn why we refer to what you are about to do as "tickling the dragon...."
 
If you change the bevel, you rebevel. Reprofile would generally mean the overall shape of the blade. "Reprofile the bevel" would also be correct.
 
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