Shaving or working edge?

[theletch1]

I'm wondering what everyones preference is on blade edges. Do you prefer an edge that is sharp enough to shave with or one that is just shy of being that sharp? For me it depends on what I'll be using the edge for. My kitchen knives all keep a shaving edge as does my smaller blade that I carry daily for SD. My Ka-bar (the large version), khukri and other blades that I carry when I'm camping or doing anything outdoors where hard contact is likely all get sharpened just shy of a shaving edge. My reasoning for this is that I always heard that a shaving edge was easier to damage or that the shaving edge made the edge more brittle. Is this a myth that I've heard over the years or is there some truth to it?

 

[Sukerkin]

Altho' I can't speak directly to the topic as I use 'long knives' {}, it is a long held truism that working blades should not be as acutely sharpened as those intended for more delicate use.

Obviously, with a sword, the wielder is putting a lot more kinetic energy into the point of contact, so a shorter blade may not be so critical when it comes to edge geometry; I would, however, think it would be prudent to err on the side of caution and not put a razors edge on a blade that's going to see some hard contact.

EDIT: Also, altho I apologise if I'm speaking words to the already wise here, when a blade is honed to a razpr edge, that edge does undergo some work/heat hardening and so becomes more brittle.

 

[SFC JeffJ]

I'm like you Jeff. Working knives about a 25-30 degree edge, SD knives at about 20, and my kitchen knives between 15-17 degrees.

The finer the edge the easier it gets damaged, at least from my experience.

Jeff

 

[jks9199]

It's a basic principle of sharpening any tool that you sharpen it according to the use you intend to put it to.

The entire goal of sharpening an edge is really to make it two-dimensional; in a perfect world, the edge would have NO width, only length where the two sides come together. The angle that you want those two edges to come together is determined by how you intend to use the blade; for some planes or chisels, for example, you may actually sharpen each side to a different angle. For knives, I tend to go with maybe between 15 and 30 or so for a daily light or multi-use (including self defense) or kitchen knives. For carving/utility use, I go a bit steeper, maybe 25 to 35 or even maybe almost 40 degrees for something like a hatchet.

What I personally find happens is that if you sharpen a blade at a smaller angle, you'll get an edge that can actually bend or distort under use, along with any issues about work-hardening or tempering the blade and making it brittle. So, that sort of angle won't hold up to more forceful uses, like woodcarving.

 

[arnisador]

I'm like you Jeff. Working knives about a 25-30 degree edge, SD knives at about 20, and my kitchen knives between 15-17 degrees.

I'm not quite so quantitative about it but I basically agree.

 

[SFC JeffJ]

I'm not quite so quantitative about it but I basically agree.

I use an Apex sharpener, so I can be really anal about the angle.

 

[Sukerkin]

I envy you in a way, Jeff as something to hold the angle constant is a godsend !

However, I still sharpen stuff the way my grandfather taught me when I was about five i.e. by eye and feel (and ear) .

That works excellently for many blades but I have found particular difficulty just recently having to do a 'repair' honing on a friends bowie shaped knife that someone had 'sharpened' to a perfect bluntness. The complex melding of edge curve and variable blade thickness made it a real challenge. The only solution I found was to work it in segments and try to make sure that I achieved an equal edge all the way along - I failed but it's good enough for camping work I reckon.

 

[Doc_Jude]

I'm like you Jeff. Working knives about a 25-30 degree edge, SD knives at about 20, and my kitchen knives between 15-17 degrees.

The finer the edge the easier it gets damaged, at least from my experience.

Jeff

You said it.

 

[theletch1]

I envy you in a way, Jeff as something to hold the angle constant is a godsend !

However, I still sharpen stuff the way my grandfather taught me when I was about five i.e. by eye and feel (and ear) .

That works excellently for many blades but I have found particular difficulty just recently having to do a 'repair' honing on a friends bowie shaped knife that someone had 'sharpened' to a perfect bluntness. The complex melding of edge curve and variable blade thickness made it a real challenge. The only solution I found was to work it in segments and try to make sure that I achieved an equal edge all the way along - I failed but it's good enough for camping work I reckon.

That's the way I was taught as well. By eye, feel and sound. For me it's more feel than anything else. I've used a couple of the sharpening tools that hold the angle steady and just couldn't get into the very well. There's just something about sitting quietly and honing by hand that relaxes me. If you want a real challenge, Mark, try to sharpen a khukri. That curve toward the base of the blade can be a real pain to get sharpened.

 

[Sukerkin]

If you want a real challenge, Mark, try to sharpen a khukri. That curve toward the base of the blade can be a real pain to get sharpened.

I can well imagine :scared:.

 

[KenpoTex]

my SD knives have a "razor" edge (probably 18-20 degrees) and I don't use them for utility. My utility knives tend to have a little more of that "working" edge (25 degrees +/-)

 

[tellner]

I don't carry knives strictly for self defense. I carry knives which are mostly used for other things but can serve that purpose. All of them have a working edge.

 

[Brian R. VanCise]

I don't carry knives strictly for self defense. I carry knives which are mostly used for other things but can serve that purpose. All of them have a working edge.

Other than a few speciality items my knives are tools that I use almost every day in one function or another. So a working edge is very important to me!

 

[jks9199]

Knife sharpening and edge holding came up elsewhere... Anyone ever used Spyderco's Tri-angle Knife Sharpener? Or some of the similar gadgets out there?

For that matter -- anyone recommend any good sharpening jigs/clamps/gadgets?

 

[KenpoTex]

The Spyderco sharpener works pretty well, I've also got a Lansky that is okay.

most of my stuff I do "freehand" with a variety of stones and ceramic rods.

 

[chinto]

a working edge just a bit shy of shaving at say 20 to 23 degrees is what I would prefer on a knife for self defense. a strait razer to shave with is about 15 degrees or so... if I want a shave, I will use the razer, but the edge on it is delicate for cutting through muscles and clothing and what have you that you may need to do in a self defense situation. However, as sharp as possible with out being delicate is good as a sharp laceration will bleed much more then one that is made by a jagged or duller blade.

 

[Baphomet]

To begin, whenever I carry a knife, they always serve as one that can be used for a dual purpose, because if I get pulled over by a cop that wants to search me, for whatever reason, I want/need to be able to explain it away. Granted, trying to explain away my EKI Karambit can be difficult.

That being said, I almost always sharpen my knives to a 20/25 degree angle and then put a micro bevel on the edge of the knive using a ceramic. I've found that this tends to help with edge retention on various mediums.

 

[Ahriman]

First of all, I make more swords than knives, so my views may be distorted...
For my knives I pick sharpness depending on the intented use - not SD vs everyday, as I have a sickness that causes that I look at even kitchen knives as combat knives.
So - thrusters get more than 40 deg, sometimes more than 50 deg for more structural strenght, cutters get somewhere around 30-40 deg and slicers get 10-20. I don't like slicers, some of my buyers do, but I feel that they are too weak. But hey, I prefer at least 8mm thick HC steel as a base material for anything over 40cm overall...:uhyeah:

 

[punisher73]

I took some training and the instructor relayed what his filipino MA instructor told him. You should have two knives. One that is kept shaving sharp for your SD needs, and they other one is for working. You NEVER use your SD knife to do anything but that.

 

[tellner]

I've heard all the usual about "I have a multitool for utility work. I keep my knife razor sharp, and it is only for cutting human flesh." It's fantasy ********.

You should keep knives sharp and in good repair, but even a fairly dull blade will cut and stab very effectively. We just aren't put together all that well. There's no need for it to be shaving sharp.

You're best at what you're most familiar with. If you use your MilSpecOp MarkVI BlackTac TinyPecker 13 with Kung Fu Grip every day you'll be familiar with it and use it easily and naturally. If you're always taking out the Spyderco and doing things with it, that's the one that will practically be a part of your hand. Why trust your life to the one that will be more difficult to use? That's simple. It adds to the mystique and makes your SD knife some sort of magic totem. It violates Musashi's old common sense dictum "Strive to make your fighting stance your everyday stance and your everyday stance our fighting stance."

I already carry around a lot of stuff. Adding an extra knife that I will almost certainly never use when I'm already wearing one that works perfectly well just doesn't make sense. If I'm carrying a pistol, I'm carrying a pistol. It's its own thing in its own place, not an extra copy that has to compete for the scarce "ready to hand" real estate.

Legally it's just stupid. Compare and contrast the following:

"Why yes officer. I have two knives because I want to keep one razor sharp just for cutting on people. I was extra careful to only use the special killing knife on him. I wouldn't want to use just any old tool for something like that. Nosiree. What do you mean 'Were you really afraid he was going to hurt you or were you looking for an excuse?'"

"My pockets? Sure officer. There's a wallet, a cell phone, a pack of gum, a pocket knife, some business cards, my keys, and an iPod. When he attacked me I was afraid he was going to kill me so I grabbed my pocketknife to defend myself."