When do you NOT want a distal taper?

S

S2nd

Joined
Oct 6, 2004
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I've been batting this around in my head for a few weeks, for no particular reason. Other than cost considerations, when would you not want a knife to have a distal taper?

Chopping hard materials?
On small knives?
 
Throwing knives and sharpened crowbars. If you are going to apply a bunch of leverage to the point you need it pretty thick at the spine.
 
I can't think of any applications where I'd intentionally not want any distal taper. But, there are plenty of blades where I wouldn't worry about it. Most blades will have a "natural" distal taper just because as the profile narrows towards the point, the grinds will get accordingly thinner. Most smaller knives won't need any more than this.

I believe the tapers, and the rate at which they taper, are important on big knives that will see hard use. Not only for better balance, but so bending and impact forces are spread over a greater length of the blade. The limbs of a bow are not completely flat and parallel; they taper towards the nocks. If they were exactly the same dimension from grip to nock, the force would all be concentrated near the center, leading to failure. Niether do they taper in a straight line from grip to nock. From the grip, they taper quickly at first, and shallow out so there's very little taper. When a blade or bow is flexed, the stress should make a gentle curve over the entire length. This is one of those engineering enigmas- "strengthening" by removing material.
 
Jeff Clark said:
Throwing knives and sharpened crowbars. If you are going to apply a bunch of leverage to the point you need it pretty thick at the spine.
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Who sharpens their crowbars? :confused: Seems like a good way to hurt yourself.
 
Very thin knives don't need distal tapers, I have some blades ground out of 1/16" stock which don't have any taper, and the point is still thinner than many knives that have extensive tapers.

I like no taper on heavy wood working knives to keep the tip stiff enough to pry with. I like taper on some utility knives as it gives you a fine point and yet a lot of stock near the handle for power cuts.

the possum said:
...so bending and impact forces are spread over a greater length of the blade.
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When using a knife as a prying tool you don't want it to store energy and rebound like a bow, you want it to be stiff. It is also very inefficient to pry with a knife when it is bent to a large angle, you can no longer readily apply force to the handle.

Rat Finkenstein said:
Who sharpens their crowbars?
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People who want to cut with them, some people even grind a point and put a handle on them to make them into fairly versatile tools.

There are actual pry bars with very thin and tapered edges used for fine woodworking where you need a thin edge. These of course are not used as wrecking pars to haul up ceramic tile underlay. They are generally not sharp and you would not want it because it would make it more likely to damage the surface of woods accidently.

-Cliff
 
Cliff Stamp said:
When using a knife as a prying tool you don't want it to store energy and rebound like a bow, you want it to be stiff. It is also very inefficient to pry with a knife when it is bent to a large angle, you can no longer readily apply force to the handle.
-Cliff
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I agree completely. This can all be achieved with a tapered blade the same as with a straight blade. It just takes more skill and knowledge on the maker's part, and probably requires starting out with thicker stock. I'm not talking about grinding down an existing blade here, but engineering a superior tool from the start. Although it would take very little metal removed from the sides to make a difference- not talking about turning it into a fillet knife. Even if the blade is so thick you can barely see it flex, it is storing the energy all the same.
 
Rat Finkenstein said:
I was unaware that "Generic" has the same meaning as "Idiotic". :rolleyes:
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I was unaware that "commonly used by a knowledgeable community" was synonymous with "idiotic".

It's an evocative, generally accepted term for that class of knives that's designed less for cutting and more for not breaking when abused.
 
Grover_Cephas said:
I was unaware that "commonly used by a knowledgeable community" was synonymous with "idiotic".

It's an evocative, generally accepted term for that class of knives that's designed less for cutting and more for not breaking when abused.
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Anyone calling hard use knives "sharpened crowbars" is not being "Knowledgeable"- they are merely expressing negative stereotypes and attacking certain makes/models of knife. This crap always seems to crop up when people ask for, or recommend knives made of thick stock- Busse in particular. If you dont like tough knives, dont buy them- but why attack them? What is gained?- only animosity.
 
Moras are not prybars and they have no distal taper, I think most people would say the are designed for cuttiing, most machetes also they have no distal taper but they are not 'prybars '
 
Rat Finkenstein said:
...why attack them?
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It isn't always an attack, some people mean it as an insult, but not everyone does.

martin j said:
Moras are not prybars and they have no distal taper, I think most people would say the are designed for cuttiing ...
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They are designed primarily for low cost. They would work much better as cutting tools if they had a distal taper and a full hollow grind, they would also be more efficient to sharpen.

This grind would reduce their scope of work though, a full flat or convex grind (secondary bevel) would keep it the same and improve cutting ability slightly and ease of sharpening greatly.

A heavy distal taper could make batoning problematic so some might want to keep the full stock thickness through the tip.

...most machetes also they have no distal taper but they are not 'prybars '
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The better ones do. Machetes are again designed to be really cheap to make, a properly ground golok with suitable balance is a much superior tool, however it costs ~10 times as much.

the possum said:
Even if the blade is so thick you can barely see it flex, it is storing the energy all the same.
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Yes, a bow just allows more, for some knives this can be a benefit because you want to increase the impacts they can take.

-Cliff
 
Ken Warner used the term "The Sharp Pry Bar" in The Practical Book of Knives almost thirty years ago. It was hardly meant as a negative expression since he went on to describe, in favorable terms, his entry in that category -- the Garcia/Hackman "Survival Knife."

He further described the "sharp pry bar" as a "serious basic tool," "railroad engineered," and something carried by "careful men" "in the odd corners of the world."

I regard the term as no more negative than "chopper."

I am happy to own four Busse knives.

'Course I also own some HI khukuris. Now THERE are some sharp pry bars -- and choppers.
 
I just bought a sharpened crowbar made by Ranger knives. The blade is wide, nominally only 6 inches long, and made from quarter inch thick 5160 (automobile leaf spring alloy). It has a full quarter inch thick tang and a completely untapered sabre grind blade. I plan on comparing its practical performance to WWII standard Cattaraugus 225Q combat knife (which is only around 3/16th inch thick of something like 1095 and a stacked leather handle). I consider the term, sharpened crowbar, to be descriptive and only critical if someone selects the style where a thinner blade would work better.

At the moment it is a challenge to cut through a cardboard box with the Ranger blade. I plan on converting it to a convex grind before I get serious with my testing. At this stage the thing is a classic "blunt instrument".
 
Rat Finkenstein said:
Who sharpens their crowbars? :confused:
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The StriderGuys have done pretty well...IMHO!:D

(Just to be PERFECTLY CLEAR I love STRIDER's tools as much as anybody and in no way mean to demean their products!!)
 
Rat Finkenstein said:
Anyone calling hard use knives "sharpened crowbars" is not being "Knowledgeable"- they are merely expressing negative stereotypes and attacking certain makes/models of knife. This crap always seems to crop up when people ask for, or recommend knives made of thick stock- Busse in particular. If you dont like tough knives, dont buy them- but why attack them? What is gained?- only animosity.
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Who said it's an insult? Why so defensive? I own several HI khukuris and I'll pick up a Strider someday to see what they're about, and I've used the term "sharpened crowbar" before in a complimentary way. Crowbars are tough as hell and can take a beating. How is this a bad thing? I love the feel of an overbuilt knife made from thick stock, and I'm proud that they feel as sturdy as a crowbar.

Chris
 
the possum said:
I can't think of any applications where I'd intentionally not want any distal taper. But, there are plenty of blades where I wouldn't worry about it. Most blades will have a "natural" distal taper just because as the profile narrows towards the point, the grinds will get accordingly thinner. Most smaller knives won't need any more than this.
Click to expand...
I didn't notice this before, but you're right. I have a feeling that I'll be going through all my knives with the calipers later today.
 
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