Why tanto?

Nov 25, 1998
In response to the thread on favorite blade shapes, I mentioned that I could not, for the life of me, see why the tanto is so popular. The blade was, I have read, designed for piercing armor and, as I and nobody I know has that need, why buy a blade that is so difficult to sharpen? I know that Cold Steel used to show one piercing a car door but I have even less need for that than for piercing armor. So the question remains "Why tanto?"
Well, FullerH
If you're going to gut animals, a drop point is probably best. If you're goint to skin those animals, a trailing point is probably best. If you're going to open packages and prepare for what you hope will never happen, the Tanto will do the job and, it just looks really cool.
One use for the tanto that gets overlooked
is in general woodworking , carpentry .They
make a finer skew chisel then the actual tool.I use a flat one side ground tanto more
then any other tool for flush trimming on
any surface.
I like the tanto blade most of all because you don't have to worry about breaking the tip like most other style blades. I always have a hard time in keeping the tips on knives from breaking, especially with ATS-34 steel. The same thickness of the blade stock remains the same from the tang to the tip on a tanto blade. This makes the tip much stronger. Can't beat it for opening heavy duty boxes, etc.

The tanto blade can take more abuse and hard work than most other blades because of the tip strength. As far as an all around work knife, can't beat it as far as I am concerned.


P.S. Must make note though that other blade styles may serve better in certain situations, and the length, thickness, and even the type of steel comes into play here, also!

I posted a thread a while back about blade styles. Out of over 50 answers I was the only one who liked the TANTO. It appears that more people do also. I agree, If you want tough and penetration the Tanto is it. It will out penetrate any other design out there, period.
"... why buy a blade that is so difficult to sharpen?"

That's strange -- one of the reasons for its popularity is most people consider the American tanto easier to sharpen than any blade with a belly, easier than anything except a sheepsfoot.

Much of its popularity comes from features that usually come with it but are unrelated to the shape -- most American tantos have more acute edge angles and stronger points than most other blades. If you compare it to other blade shapes sharpened to the same angle and with an equally strong point most of the apparent advantages evaporate. It still penetrates better than any blade with a belly, but a belly is useful for many purposes -- the American tanto is not the best choice for an all-around knife.

One advantage I seldom see mentioned except by James Matttis is it's a great steak knife -- only the secondary point contacts the plate and gets dulled. I'm thinking about making a set of American tanto steak knives and throwing out my serrated steak knives -- I hate serrations.

One of the tanto shapes samurai actually used is worth considering -- a perfectly straight spine with no drop or clip, flat ground on both sides, and with just a little belly to it -- the edge looks like an American tanto with a little curved section instead of that angle. That shape has many of the advantages -- nearly as good penetration -- without the disadvantages. It's pretty easy to convert an American tanto to that shape, especially if you start with one that's ground on both sides to begin with -- just round off the secondary point and make it into a high saber or flat grind.

-Cougar Allen :{)
Cobalt, you wrote:

"if you want tough and penetration the Tanto is it", and followed up with talking about how the tanto will outpenetrate other knives.

We should be careful here. According to the way most of us use the term "penetration", the tanto is easily the WORST at penetration of any popular format. That the tanto has great penetration is the biggest and most incorrect myth among tanto fans. It is good at penetration *only* in the sense that the tip is strong; beyond that, actual penetration ability stinks.

As far as penetration goes, you want as *little* metal up front as possible. An icepick or dagger, say, and go up from there. Of course, then you have a weak point. If you load up as much metal as possible up front, you have a very strong point (like a tanto), but that point format kills the penetration ability. It's a simple tradeoff -- lots of metal up front and lots of strength but bad penetration, or little metal up front and great penetration but little strength.

If you need great point strength and don't mind bad penetration ability -- for example, if you stab your knife through car doors a lot -- a tanto-style tip is a fine choice. Otherwise, a sabre-grind drop point will do almost as well, and at least it has a belly for utility work, and the point is dropped for better control during utility work. Even on a knife that I'm going to really work the tip on, I'd almost always rather have a more useful blade shape, and make up for point strength with better materials.

I despise American tantos with a passion that is only exceeded by my loathing of chisel grinds, macro serrations on non-bread knives and liner locks in general. Nonetheless, Cougar makes an interesting point when he mentions re-shaping them to a more traditional Japanese less angled style.

I reworked a CS L Voyager into what I call a "Sod-buster" shape. The resultant point profile is very similar to pics I've seen of period Japanese tantos, but I call it the Sod-Buster shape since that image seems to clarify things a bit to folks used to modern designs. It's simply amazing how grinding off the acute angularity and giving the knife some belly changed it from a knife I hated to a very, very capable working knife. If your like of the stylized American tanto has more to do with tip strength than asthetics, I'd urge you to try that simple mod on one of your own Am. tanto shapes. To me, I gave up nothing and gained an acceptable knife. Not too surprisingly that mod also somewhat increased the knife's penetrative capabilities, though nothing with that much forward metal will ever be a great or even a good penetrator.

Most funny is that some makers have commented that getting the multiple bevels angled just right on an American tanto shape is far harder than making one continuous curve with belly. Seems to me that they could make a far more useful knife by opting for the easier to make radiused curvature.

What I mean by penetration is shoving it into something hard with minimal damage or deflection or bending of the blade. I once tried shoving my tanto, bowie, clip point and dagger style knives into the chest of a wild boar(Just killed). Guess what penetrated the best, you got it the TANTO. The chest of the wild boar is grissle which is very hard, sp hard in fact that my bowie did not penetrate it well and neither did the clip point. That dagger did well, but I ended up with a bent tip. The tanto(SPECWAR) had no damage whatsoever. That is what I mean by penetration. It has a reinforced tip and is very sharp and pointed. And I still stand by my statement that it will out pewnetrate most anything out there. Now, I will agree that a saber grind may be as good, but the point angle of the modified tanto's seems more amenable to penetration. My opinion on that.

MPS: I have a folder with an interesting blade that I had Allen Elishewitz make up for me. It's a classic drop point blade, but ground like a tanto -- that is, the front-facing edge has a separate, flat grind to it. Very strong point, but otherwise a drop-point (with a belly). It's nice, but I've found that like a tanto, my Elishewitz folder penetrates badly -- I like sharper points that penetrate well on my carry folder.

Cobalt: Testing's the way to go, perhaps more needs to be done. I'm not sure what went wrong with your test, I don't know if every knife hit bone or something except for your tanto, or if the bowie was particularly thick-pointed. But I've tested tanto versus other points in just about everything, from meat to phone books to wood to whatever, and pretty consistently find tantos in the back of the pack. I'm reasonably confident of my findings, because everyone I know who has tested this (except for you, you're my wayward datapoint
) has seen the same thing, with the tanto penetrating badly. I include in this numerous guys who hunt boars and essentially tested their knives in them -- none of them carry tantos. Check out the points on Harley's pig stickers for example; they're pretty much as you'd expect them to be if you believe what I said about good penetration. And that's a guy who has done some serious testing!

MPS, you've done a lot of testing, what have you seen of Americanized tanto point penetration, versus say a flat-ground clip-point (sharp false edge or not), at the same spine thickness and blade width? How 'bout versus a dagger or drop point?


[This message has been edited by Joe Talmadge (edited 20 February 1999).]
Joe asked what I've seen in testing tantos
(hey will somebody pleez email me with how one properly quotes text in this format? I'm sorry to be so obtuse)

Anyway, I've tested, and posted about many, many tests I've done involving tantos vs the rest of the world. Bottomline is that in everything from hanging deer to 1/4" luan plywood to boxes full of rags to foam rubber to cardboard to whatever, the American tanto loses badly to nearly everything in terms of penetrative power.

My guess for Cobalt is to take a long hard look at handle to point ratios and relationships. For an interesting data point, one of the best penetrators that I've ever seen is the "sheffield" style CS Bush Ranger. Tested against CS tantos, AG Russell Bowies, other CS knives like the SRK, and a couple of double edged daggers, some bayonnets, etc. the CS bowie simply blew away the competition. The reason is that it has a very thin pointy point that is in good line with the natural thrust and is reinforced not by being too thick, but by being W I D E.
You ought to see the difference in cuts between a wide, (but not thick) bowie shape and a narrower, but thicker tanto shape. Absolutely impressive.

One of the coolest tests I did involved suspending the knives via a rope and pulley attachment and letting the force of various weights attached to the knives carry them into such mediums as tires, plywood, paper etc. I did that primarily to eliminate the human subjective factor. The results mirrored the results I'd gotten by hand. The wide thin pointy blade wins in penetration. In theory a narrower blade should do even better, but my subset of test knives did not include any knives that were both narrow thin and strong. Modern alloys might seek to alleviate the deficiency that exists in many older knives that forced the maker to make narrow knives too thick for their width. In theory an icepick ought to win, but it has no cutting power and thus is subject to more deflection than something that literally cuts it's way it. So penetration is really a mix of both cutting and sheer strength. Methinks that in some ways the Midevil (sp on purpose) concept of a 3-4 edged star shaped armor piecer had much merit.

My first knife love, and the one that started my continuing fascination is the Bowie. It started with "The Iron Mistress", "The Jim Bowie Show" (I can still sing the theme as others my age sing Paladin's theme), and Raymond Thorpe's "The Bowie Knife", so I will give way to nobody for love of the Bowie knife. But I would never consider it for penetration. It was intended as a slashing weapon and general utility tool, never a dirk! If I were seeking a knife for penetrating unarmored targets, it would be the stilleto shape or, perhaps, the Fairbairn-Sykes dagger. The widest that I would consider would be the "Arkansas Toothpick" style. As I said before, if I wanted to stab car doors or armored persons, then I would consider a tanto as that was its intended purpose.

Thank you all, however. I am enjoying and learning from the discussion. I had not considered the possibility that it could be a woodworking chisel.

[This message has been edited by FullerH (edited 21 February 1999).]
I fall into Joe`s camp on this one. I`ve had several tantos over the years and never found that much use for them. They`re not too bad on a narrow blade like the StiffKiss (or the concealment knife I just made) but they have little use on a big sturdy using blade as far as I`m concerned. I few tests of my own have shown that even the very wide blade of my EDMF trench bowie penetrates far better than any of my tantos. I attribute this to it`s accute point and sharpened false edge,both lacking in conventional american tantos. Marcus
(sorry... nevermind)

[This message has been edited by pk (edited 21 February 1999).]
This is rare -- I'm actually disagreeing with Joe. There's an optimum angle -- I'm talking about the angle between edge and spine here, not the angle you sharpen the edge to -- there's an optimum angle for penetration and if you diverge from that angle to either more obtuse or more acute you impair penetration. Let's see if I can explain why....

Archers worked this out long ago and maybe it's easier to visualize in an arrowhead -- the same principles apply to knives when used in a pure thrusting motion. Imagine a simple single-blade arrowhead with straight edges. At one extreme it could have a very obtuse angle between the two edges, almost a straight line -- then it makes almost a pure pushcut with very little slicing action. At the other extreme is a long arrowhead like the classic Arkansas toothpick dagger shape -- that makes an almost pure slice with very little pushcutting action. Optimum penetration is achieved with an angle between the extremes with just the right proportion of slicing to pushcutting. A arrowhead that's too long creates a lot of drag as those long edges slice their way into the target -- it looks to the layman as if it would penetrate with the greatest of ease, but in fact it'll slow down and stop long before the optimum profile will. Next time you're in a sporting goods store look at the arrowheads. You'll notice most of them have nearly the same angle with very little variation between different brands. That's because that angle penetrates better than any other, either more obtuse or more acute.

A blade with a belly has a varying angle, tangent to the curve of the edge. It might be close to the right angle for best penetration near the point, but as the edge curves the angle tangent to it grows more acute and it starts slicing more than pushcutting as you penetrate deeper into the target -- bad.

Naturally to compare blade shapes you have to test blades (or arrowheads) with the same thickness and width.

The optimum angle depends somewhat on the target material, as some materials respond better to pushcutting and others to slicing. Arrowheads are made to penetrate animals, hide and bone and meat. If you test on a phonebook or wood you might find the optimum angle is a little different, but you'll still find a tanto profiled to that angle, with no belly, will penetrate better than a blade with a belly that only has the optimum angle on part of the cutting edge.

Some of the tantos on the market taper all the way to the hilt. The designers of those blades missed the point of the design, at least as far as penetration is concerned. They still make good steak knives, but although they'll penetrate well up to the secondary point, after that the angle becomes much too acute for good penetration and penetration will come to a stop long before you reach the hilt. A properly designed tanto does all its cutting with the short edge and the long edge might as well not even be sharpened as far as straight thrusts are concerned.

Tests on car roofs and steel drums may look extreme, but anything can penetrate meat -- you can penetrate meat with a fork. Cutting your way out of a car, making a hole in a steel can or a skull or a rib cage or armor with trauma plates -- they're actually practical tests, and they're tests not every knife can pass like penetrating meat. Or jello.... It's not very hard to penetrate a cardboard box even with a blade profile that's far from ideal, but you will notice it takes much less effort with a properly designed tanto than, say, a skinning knife that's all belly.

By the way, if you test on bone use green bone. Dried bone is much harder and arrows bounce right off it.

-Cougar Allen :{)
Well if you really want to talk penetration, and not cutting or bleeding power, then next time you've got a deer already strung up fire a bullet shaped target point through it. Unfortunately, that might not tell you much because assuming it doesn't hit bone most broadheads will easily penetrate all the way through a deer as well.

Comparing an American tanto point to a broadhead is a little off, though I'm afraid. The reason that American tanto points consistantly do so poorly in penetration tests is because they most often transition to the full spine thickness too quickly.

For instance, I mentioned that one of the best penetrators I've got is a CS Bush Ranger "Sheffield" Bowie style. It's far more like a flat blade broadhead than most American tantos. Unlike most Am tantos and most other more traditional clipped Bowie shapes the thin tip doesn't transition to full spine thickness for 4 inches. That plus the point is directly inline with the center of the handle, rather than being higher than the angle of thrust.

Actually, I'd never thought about it before, but the tip on it is almost exactly like a very slightly curved half of one of the better traditional flat metal broadheads used with longbows. Hmmm. In the first inch it widens to only 7/8" and is only 1/16" thick for that first inch. At 2 inches, it's still only about 1/16" thick. (Sorry, can't find calipers.)
Compare that to your favorite Am. tanto. I bet it's considerably thicker.

Cougar, interesting point about finding the exact best penetrating angle. It's something I haven't looked at much, since I've found I can predict penetration performance by the "how fast the point thickens" hypothesis. I have noticed that when it comes to knives, the most extreme angle seems to penetrate best, provided the point is strong enough. That goes against your arrow example, though. I still basically expect that the less metal up front, the better the penetration.

I will, however, agree with Mike on why the tanto doesn't penetrate well, and don't think it has much to do with the primary edge angle. The Americanized tanto's biggest inhibitor to penetration is the "reinforced point", that separate thick front grind. That's what provides a lot of the tanto's great point strength, and it is also the tanto's greatest penetration inhibitor. If you want to go with a tanto that has a full flat grind (and maybe a distal taper), like the MD Taiho, then I expect better penetration in that case. But that's not what everyone here is talking about, especially when they're talking about the tanto's great point strength.

Testing-wise, I often test in either wood or phone books (aside from other tests). That way, it's less a test of point strength since wood and paper are soft. However, a knife needs great geometry to get very far in those mediums. That tanto's penetration liability is immediately visible in those things.

I do agree with you again about a tanto perhaps penetrating better than a skinning knife that's all belly. Again, though, I tend to explain this in terms of how quickly the blade thickens -- in this case, from top to bottom. Something like the Emerson Commander, for example, has a dull point and a lot of belly, and won't be the best penetrater. The AFCK has a sharp point and less belly, and penetrates like nobody's business If I modify the belly to be at roughly the same same angle as the tanto's primary angle (roughly, because as you point out the belly's angle changes), then the tanto's reinforced point becomes a significant penetration inhibitor.

That's how things have tested out so far!

OK, I still can't find the Browne & Sharpe dial calipers that I was looking for but have found a simple brass set that reads in 32nds" that should be good enough to give some better data than I gave before.

Here goes, measuring the CS Bush Ranger from the tip at 1" it is 3/32" thick, at 2" it is 1/8", at 3" it is 5/32" and at 4" it is the full spine width of 3/16". Now compare that very gradual increase in thickness to the CS Recon Tanto, which while being nominally the same spine thickness of 3/16 gets to almost full thickness in under an inch. (That's from memory. I sold mine long ago when I realized how deficient the design was.)

So I was a little bit off in my guesstimated measurements eyeballing it against a wooden ruler, but the point is the the CS Bush Ranger is the better penetrator because it is slimmer for more of it's point and thickens far more gradually. Clearly the tradeoff is in point strength, but in terms of pennetration it wins.

Even on the Kobun, which is nominally a scant 1/8" spine, it still is gonna get to that full thickness of 1/8" well prior to the 2 full inches of gradual taper on the CS Bush Ranger.

Another interesting, and perhaps even more relevant comparison is between folders like the AFCK or the Eclipse and similarly sized CS Voyager tantos. Look at how gradually the BM's taper to full 1/8" width as compared to how abruptly the CS tantos make that transition. Now try stabbing various mediums. Not too surprisingly the more gradual taper of the pointy BM's wins in all mediums that I'm willing to try them in. (NO, I don't do car doors, hoods, etc.)

hope that helps,
Now that I understand were everyone is comming from, I will agree that a thin spear type point will out penetrate a typical tanto, "in soft tissue". However, the tanto will completely outperform these other blade styles into hard obejects. Go ahead and take that CS knife and do what Tactical knives did with the specwar in their 1/99 issue. Try punching through steel drums and car doors repeatedly with it. I think you will find yourself with a damaged tip in short order. Not so with the tanto's. I have never had problems with penetration with tanto's in the real world and prefer the extra strength they provide over the average knife. I know I won't be in the middle of nowhere with a broken or bent blade because it was 1/16 inch thick for the first 4 inches. I might as well have a kitchen knife since a good one is about that thick and can probably penetrate as good.
Cobalt -- I disagree on so many points I don't quite know where to start
Please don't take anything personal in the following rant, I'm enjoying the discussion, but didn't have time to do my normal softening-of-editorial-voice editting!

When you talk about being in "the middle of nowhere", I think that's a particularly bad example. For most survival situations, you'll want to chop, or dress game, or do other things that a tanto is not optimal for. And fighting is normally a game of optimum soft-target (like leather or even soft body armor) penetration -- again, bad for a tanto. And I can't imagine what you'll be doing with the point of that tanto that you might break a well-made clip point tip, especially considering how otherwise unsuited the tanto is as a general-purpose blade. So your example of why you want a tanto is ironically a great example of when you don't want one!

But okay, let's get back to tip strength. I think it's just playing word games to say the tanto is a good penetrater. Provided the non-tanto's tip isn't damaged, the tanto is simply the worst-penetrating point going. And getting stong-enough points on a clip- or drop-point without the serious compromise of penetration ability (ala the tanto) is just not that difficult. The Bush Ranger's point may or may not break when shoved into a car door (and I again question why you need this much point strength so badly you're willing to give up so much else). However, there are plenty of clip points that can easily make it through a car door with no damage, and that will penetrate more easily than a tanto. And with the clip-point's point in-line with direction of force, you get better control and better transfer, in my experience. Choose your clip- or drop-point carefully, you'll get better penetration even in hard targets, and better just-about-everything-else too, than you would have with a tanto.

Again, saying a tanto will "completely outperform these other blade styles into hard objects" is just plain wrong, especially if you're going to be realistic about the "hard objects" you're referencing. It's military guys I most hear about putting knives through steel drums, but I don't see Les pushing tantos more than anything else. Some of those other blade styles will break, going into the examples you gave (steel drum, car door). Many won't, and the ones that won't will easily outperform the tanto. Almost anything that doesn't break will outperform a tanto at penetration, it's as simple as that.

And there's a tradeoff here with the tanto's point strength versus just about any other use. Unless you punch steel drums for a living, a well-done clip point in good steel will outperform the tanto -- especially point penetration into hard or soft targets -- in just about every situation most people will run into. Even steel drum wise, there's plenty that will make it through.

Of course, it does seem odd to me that you're placing "punch through car door" more highly than other functions, but even that way, the tanto isn't a clear win...


[This message has been edited by Joe Talmadge (edited 21 February 1999).]