Blade Setup: Tang Bend = Lighter Feel?

[prototoast]

Originally Posted by erooMynohtnA

It makes me think there may be some lever/torque reason behind canted blades feeling better, but that requires more trig than I want to do (which is any). I hope that helps.

Your reasoning isn't bad, but you are thinking too linearly. The important thing to note is that when you bend it, the center of mass moves off the blade. The balance point of the weapon (by your seesaw example) is no longer at the center of mass. When you then consider that the point.

You should also note that regardless of how the weight is distributed, it is still always rotated about the same point (some point around your wrist/hand). When you bend it, you are moving more of the mass (radially) closer to that point. The guard portion remains unchanged, but the blade moves slightly closer (imagine extreme cases of 90 or 180 degree bends).

[erooMynohtnA]

Originally Posted by prototoast

Your reasoning isn't bad, but you are thinking too linearly. The important thing to note is that when you bend it, the center of mass moves off the blade. The balance point of the weapon (by your seesaw example) is no longer at the center of mass. When you then consider that the point.

You should also note that regardless of how the weight is distributed, it is still always rotated about the same point (some point around your wrist/hand). When you bend it, you are moving more of the mass (radially) closer to that point. The guard portion remains unchanged, but the blade moves slightly closer (imagine extreme cases of 90 or 180 degree bends).

It is just an example. And it is incomplete. You're right that the center of gravity and the center of balance are different, but it's close enough in the case of the cant of blade to give an accurate approximation. I also took a few other shortcuts.

I don't think that a blade is rotated about the same point in your hand all the time. Depending upon which fingers are applying force and how much, that's going to cause slight differences. Besides, for every torque you apply to the weapon, it's applying the same torque back at you, so weight and balance become a factor.

[prototoast]

Originally Posted by erooMynohtnA

I don't think that a blade is rotated about the same point in your hand all the time. Depending upon which fingers are applying force and how much, that's going to cause slight differences. Besides, for every torque you apply to the weapon, it's applying the same torque back at you, so weight and balance become a factor.

What I mean by that is that the point it is rotated about is the same, whether or not there is bend in the tang.

[luv2fence]

Words from a novice. Check me on this.

A canted tang facilitates an oblique angle
of attack to the opponents chest or inside
arm, while keeping your hand in a more
neutral (unstrained) position. This is the
major reason for the canted tang.
Lefties screw this up for a Righty, so the
Righty must hit Lefties in the flank or
back more often.

If a tang is canted too much, a mechanical
advantage is lost; the opponent can circle
your blade and twist the (French) grip while
in your hand. It has happened to me, 2 much.

With French grip, at on guard in 6, the foil
is pointed at the high chest or mask of the
opponent. With a canted tang, the hand can
be more straight from the arm, less strained,
more neutral.

I have never felt a lightness that I can attribute
to a canted tang.
For the short bouts that I do, even heavy weapons
feel very light: due to adrenaline rush.

luv2fence

[Inquartata]

Originally Posted by Craig

You actually posited this as your conclusion. Hence, burden of proof is on you to prove your claim that this is placebo effect.

While I admire the subtile artistry of your wriggling and squirming, I am of course not swayed by it.

Mr. Epee asked why canting the blade should make the weapon feel lighter. ( Well, he first averred that "everyone" had probably noticed that this is so, and that is refuted by a single counterexample, such as my own. )

A string of posters then advanced a number of explanations...for a phenomenon which isn't even remotely proven, eg that in fact canting the blade makes the weapon feel lighter. Yours was one of the more emphatic confirmations of this unproven effect:

"I build weapons...daily...and canted blade=better balance/feel, in all 3 weapons".

Here is where it becomes incumbent upon you to prove the claim. You then say:

"Empirical evidence with a sample of 1 observer and an unknown number of repetitions>100".

Which of course is no proof at all---any more than the Pope's fervent belief that God exists and that he has experienced His presence proves the existence of God. In both cases we are in the realm of faith; subjective feelings are useless as evidence. However, to go still farther I adduced my own experience with holding both canted and uncanted weapons and discerning no feeling of one being lighter or better balanced. As counterexample any one "feeling" suffices to cancel out another "feeling".

My assertion remains: The putative feeling of greater lightness is an illusion. This is the only alternative. Insofar as there has been NO evidence presented in support of a physical effect from canting tangs, said feeling can only arise from a psychological effect. That is, illusion. Expectation. The placebo effect. It is the only remaining possibility as far as I can ascertain. ( If anyone can think up a third possibility, feel free to say so. )

This is not a "conclusion" on my part. It is a noticing of the only possible alternative to yours, absent any proof of yours...

And so the burden of proof is still on the person who believes in unicorns ( that's you ) to prove that they exist...not on me to prove that they don't.

I provided evidence, from personal experience, that it is not placebo effect and that there is a noticable shift in feeling of straight vs. canted tang.

Except that it's not really "evidence", it's an idiosyncratic subjective impression explicable in at least two ways.

If I "have a feeling" that there's an intruder in my house, does that mean there IS an intruder in my house? Or can my "feeling", however strong, have zero basis in reality? It isn't evidence of anything, is it?

Your only response is "I don't believe you, prove more."

Yes, pretty much. It's all that's required of me. You assert, I question, you either prove or the assertion falls.

But really, it's not "prove more", it's "prove something".

At this point, those with experience in the matter all know that there is an effect.

Argumentum ad numeram. The number of people who believe a proposition has no probative value in determining the truth of the proposition. And calling it "knowing" instead of "believing" doesn't strengthen the case.

At this very moment, we live in a country where according to a Gallup poll 2/3 of the populace believe that a man named Jesus rose from the dead---not metaphorically, not allegorically, but literally. It believes this with no real evidence. It simply "knows" this happened. The correlation between what you and those who agree with you "know" and objective reality is probably no greater than that between the faith of any religious person and objective reality...

BTW, I feel that I should point out that your assertion that "those with experience in the matter all know" is not correct, either. Cast your attention back through this thread, and you will find that Keith also is dubious, and By Sword claims to feel no difference between a canted and an uncanted blade he owns. Add their dubiety to my own.

Edit: And now add luv2fence.

It is up to you to prove otherwise if you want to continue your little game.

Sadly for you, it is not.

"My little game" is that of logical debate. You can choose not to play, but you cannot simply declare victory on the basis of "feelings".

[Inquartata]

Originally Posted by keropie

Additionally, burden of proof only lies on those attempting to prove a statement, a category into which you seem to fall as well. Even leaving aside the placebo statement, you are certainly arguing that a straight tang is better, not simply that there is no proven benefit to a bent tang.

No; reread what I wrote. I said that I discerned no difference between a straight and a canted tang on a weapon. That is MY subjective "feeling", which is evidence of nothing but itself. I nowhere said that a straight tang feels "better" or performs better. Though I did adduce some things about thrusting weapons, the shortest distance between two points, linear vectors and the like. These would seem to me to imply some things pretty strongly...but the canted-feels-better camp has not even refuted these implications...

Oh, and from personal experience, you're wrong. And since I'm going to use my weapons personally, I will continue to bend them before I use them.

You are of coure quite welcome to do so. You are also welcome to wear your lucky socks and touch your rabbits foot before fencing, and to scream after touches. I suspect that they will all prove about equally efficacious. Certainly all three are of equally unproven utility.

Meanwhile, asserting that I am wrong does not of course mean anything whatsoever. It proves as little as as Craig's ( or my ) "feelings".

And comparing current fencing weapons to historical weapons or arguing that foil was a training weapon for rapier has no bearing whatsoever. An epee today has nothing but bare resemblance to an epee from Napaleon's army, and foil is no longer used as anything but a sport weapon.

Echoes of that old "I reject all of your analogies because they are inconvenient" song of DHCs.

A sword is a sword. They are all designed to do the same thing: Insert point A into opponent B. In this simple function they, and indeed spears and daggers and pointed sticks, are alike. Deny it if you like, but if a foil with a canted grip ( and its "feel" ) is a data point, so is every sword. And the number of those with straight grips dwarfs those with canted ones. This speaks to preference, and thus to "feel". Manifestly, the majority of all the sword-users who have ever lived have used and preferred the "feel" of straight grips. Even if you insist that subjective "feel" and personal preference constitute evidence, those who believe cants to be best are in a tiny minority. Ergo...

The real answer is that it depends on who you are if bending your tang is right or wrong, and even more so on how much to bend your tang. Experiment, and find out.

"We must respect the other fellow's [ tang preference ], but only in the respect and to the extent that we respect his belief that his wife is beautiful and his children, smart".

In the final analysis, you are right. Even if the matter can in fact be attributed to nothing more than the placebo effect, well, the placebo effect can be useful in some cases. If you think something makes you fence better, you may well fence better, even if the real cause is the greater confidence it gives you instead of the something itself. Mistaking the cause of an effect does not dissipate the effect.

But as for me, give me a proven thing over one fervently believed without evidence any day...

[Inquartata]

Originally Posted by Tomas N

I appreciate the point that we could, with enough time and money, do a set of controlled experiments that would "prove" whether or not the blade feels lighter.

I might just do some experimentation. The outcomes of bouts between myself and my practice partners generally follow a roughly consistent pattern. If I can persuade some of the canted-grip aficionados to trade sabres with me for a few bouts, the results might be at least slightly revealing. If a canted tang really makes for an improvement in performance, or if conversely a straight one causes a deterioration in same, it ought to be detectable: there ought to be a departure from the rough pattern.

Maybe after Nationals....

[Inquartata]

Originally Posted by erooMynohtnA

Canting the blade does not move the point of balance toward the hand. It moves the point of balance toward the tip. If you don't believe me, you can try a simple experiment (I've done it myself to make sure). Balance a piece of wire (or whatever you can bend) on a narrow surface (edge of a saber?). Bend one side of the wire about midway away from the saber blade, if the bend is severe enough the weight will shift to the opposite side, and it will fall, while the side that is bent will rise. That's because the center of gravity has moved to the side that it not bent.

Fascinating. You are correct; I just tried it with a straightened wire coat-hanger, and the COG did indeed shift forward. Doubtless there is some explanation in physics, but I am not a science person and so wouldn't even know where to begin to look.

I had to bend the one end of the hanger to almost a 90-degree angle to get much of a shift, of course. However, still very revealing. Now, if only someone had adduced something of this sort as evidence in the beginning, instead of relying on "feelings", we might have spared ourselves three pages of wrangling.

Thanks, Erythromycin.

[erooMynohtnA]

Originally Posted by Inquartata

Fascinating. You are correct; I just tried it with a straightened wire coat-hanger, and the COG did indeed shift forward. Doubtless there is some explanation in physics, but I am not a science person and so wouldn't even know where to begin to look.

I had to bend the one end of the hanger to almost a 90-degree angle to get much of a shift, of course. However, still very revealing. Now, if only someone had adduced something of this sort as evidence in the beginning, instead of relying on "feelings", we might have spared ourselves three pages of wrangling.

Thanks, Erythromycin.

You could always look at my post detailing the dynamics of two children on a seesaw. It's not perfect, but it is an accurate representation of the bend of the wire or the cant of a blade. Besides, I'm sure you enjoyed the three pages of wrangling more than anyone else (although, I'll admit, I enjoy reading it too).

If you'll note, while I don't agree with people that it shifts the balance down the blade, I do think that canting the blade makes it feel lighter. There is certainly a method of measuring forces, angles, moments of inertia, grips, and many other variables to determine whether a cant gives a biomechanical advantage that results in a lighter feeling blade. However, that's way more work than I'm prepared to do without a grant.

As a counterexample to the placebo effect: I didn't know a blade was supposed to feel lighter when it was canted, but it did feel lighter to me (I did it because people said it made it easier to hit the flank on righties as I'm a lefty, and I didn't know it was supposed to feel different in any way). I knew I had not changed the weight in any way, so no expectation could be fulfilled by it feeling either lighter or heavier. One could even say I had an expectation that it would feel the same, so I would be biased to feel no change at all. Perhaps, a bias to which you have succumbed?

[Alex_Paul]

All I have to say on the matter is

This is a classic thread...Sorry, I realise that this is not a helpful coment but I felt I had to post.

My two penneth is that the coat hanger proves the opposite because you are not holding the blade at the c of g. The blade is being held at by the fingers effectively on the straight end of the coat hanger. if you take a coat hanger and wave it about in front of you holding just a small part it will feel quite heavy because lots of the mass is far in front of the point you are holding. If you then put a 90 degree bend in it just in front of where you are holding it this moves the mass to almost directly below your fingers and it will "feel" lighter. This however is a ridiculously extreme example and I am skeptical as to wether the difference with a much smaller bend would translate into a real fencing weapon feeling lighter...

[Inquartata]

Originally Posted by Alex_Paul

I realise that this is not a helpful comment but I felt I had to post.

Now you are channeling me, I see.

[noodle]

Originally Posted by Inquartata

Nothing in the rules of billiards forbids the use of a cue with built-in angles designed to let you hold it in an offset grip. Wood can be bent ( think of canes ) and were there any advantage in it I suspect that someone would have done it. And of course swept the pool world with this obviously superior device.

And yet...




Yes. Again, why is the rear hand not grasping the cue at an angle, and why are there not cues designed to make this easier and impart a "better feel"?

Because such would have no real ergonomic utility.



So power is not a concern? You haven't ever broken, then? Or seen someone else break?

And---do you really think control is secondary to power in using a fencing weapon? You must, otherwise this line of argument makes no sense to me...




And would soon discover that it yielded no advantage, I daresay.




Eh...you use a 30-foot cue?

Um...have I mistaken you for someone familiar with the game?




There is no rule requiring straight cues. Well, not apart from the rules of common sense...

Entirety of the Material Specifications for cue sticks ( from http://www.wpa-pool.com/index.asp?content=rules_spec ):



Nothing there about shape, you'll notice. Design away!






For both. From the Celtic and Minoan rapiers to the estoc, the Renaissance rapier and the smallsword, all thrusting weapons, the grips were perfectly straight, every one of them.

The Indian pata and katar ( or punch-dagger ) had transverse grips. They are widely regarded as extremely limiting weapons to use, and were most likely failed experiments. In certain later Middle Eastern weapons such as the shamshir, the grip tended to curve at the bottom in a superficially pistol-grip fashion. However, the purpose of this terminal curvature---and the bulk of these grips too were straight for most of their length, curving only at the pommel end---was to make for a more secure grip, ie to keep the weapon from slipping out of a sweaty or bloody hand. There are indeed a few extant examples of swords with offset grips, such as the so-called Sword of Charlemagne. These too were probably unhappy experiments which were never widely adopted or imitated.

And note, the shamsir, like the Japanese sword, was almost entirely a cutting, slashing weapon. I cannot think of a weapon intended for the thrust which featured a curved grip or a canted tang.

For that matter, note that spears and other polearms have also had almost universally straight shafts. These too were thrusting weapons...and I take it that you do not allege that these did not call for strength in their employment?



So was the pata...but it did not prevent the use of a transverse grip. Neither was the feature found to be very useful.



A) The point IS used in modern sabre;

B ) The point was widely used with the cavalry sabre; indeed later sabres had straight blades and users were trained and exhorted to give point in preference to the cut;

C) The real sabre and its ancestor the shamshir is one of the few weapons which DOES in fact have a grip with some curvature. It is of some conceivable utility on a cutting, slashing blade. Driving a point home however is not really helped by such a grip, as far as I can tell.




Actually, that point was in regard to Craig's allegation that his personal experiences constitute some sort of proof that a canted grip is "better" than a straight one. The history of sword use, including the use of swords on which the users life depended, does not bear this out....and the number of data points is much larger than his...or DHC's...or those of all the fencers and armourers on this site put together.

Note too that the abacus and the computer are rather more different from each other than are, say, the smallsword and the epee. And the number of data points for computer use dwarfs those of abacus use.

Nice try, though.



End an elegant public address by hawking and spitting at the audience. Nice...

Still an ad hominem, and still the mark of a debater who has run out of resources.

quit trying to straw man this. you're arguing that the straight grip is better than visconti, not that a cant in the blade improves blade feel, which is what this thread has been about.

the ammount of force applied to the blade are equal with both situations (straight/bent, pistol/french, whatever). i can draw you free body diagrams of this. someone mentioned earlier that the center of gravity changes, but that is patently false since its based on mass and there is no change of mass. the change in the force interaction with a cant is between whatever grip you're using and the support your hand can provide. this is why it feels more comfortable and lighter, because there are stronger muscles supporting the tip.

if i get bored, i might actually do some sort of project based on this.

[noodle]

i want to expand on my previous post a bit, i had to cut it shorter than i wanted -- center of gravity wont' change, but the moment of inertia will change by shifting a bit toward the bell. this will make controlling the tip a bit easier. can also draw a nice fbd to show this, but it'd be estimated and pretty simple.

[Alex_Paul]

Originally Posted by noodle

the change in the force interaction with a cant is between whatever grip you're using and the support your hand can provide. this is why it feels more comfortable and lighter, because there are stronger muscles supporting the tip.

seems like the only sensible argument for the "feeling" of a blade being lighter other than placebo.

Nice work... If you want to do a funky drawing I am sure we would all love to see it.

Alex

[erooMynohtnA]

Originally Posted by noodle

quit trying to straw man this. you're arguing that the straight grip is better than visconti, not that a cant in the blade improves blade feel, which is what this thread has been about.

the ammount of force applied to the blade are equal with both situations (straight/bent, pistol/french, whatever). i can draw you free body diagrams of this. someone mentioned earlier that the center of gravity changes, but that is patently false since its based on mass and there is no change of mass. the change in the force interaction with a cant is between whatever grip you're using and the support your hand can provide. this is why it feels more comfortable and lighter, because there are stronger muscles supporting the tip.

if i get bored, i might actually do some sort of project based on this.

I don't take issue with your conclusion, just the way you got there.

The moment of inertia changes (at least if you use the blade for the axis of rotation). The balance changes. The center of gravity changes.

By the argument you use against a change in center of graviy, I could bend a foil in half and stick the handle on the tip end, and the center of gravity would still be the same, because there has been no change in mass. A center of gravity is not simply how massive an object is, it is fully dependent on the distribution of that mass. By that same argument, the children on the seesaw would never move because the mass didn't change, and the wire that Inquartata bent wouldn't have moved. Also, there is a change in mass, not the overall mass, but where that mass is placed, and that's all it takes. If you change the shape of something, you generally change where the center of it is.

Also, the moment of inertia is based in mass as well. It's angular mass. It is how the mass in the object reacts to angular forces (or torque if you will). You have to define the axis about which the weapon is to rotate, and from there you get the moment of inertia which is a number denoting the resistance to movement in kilogram meters squared (meters is squared not kilograms). The number can either get bigger or smaller. The moment of inertia is a highly specialized phrase, and it does not "shift," because there is a defined axis for any moment. Although, a center of gravity (or mass) does because it is a point in space, not a number. You can change the moment of inertia for an object drastically by simply changing the axis about which it rotates.

However, I also believe all these changes are small enough to the point of being negligible, which is the way to argue it. Not that it simply doesn't happen and to eschew the physics describing it and how negligible it is.

You're firing from the hip with physics terms, and it's not helping anything. I do believe that you're correct that stronger muscle groups are utilized when a blade is canted. But, I don't think an argument rooted in faulty physics is the way to prove it.

[noodle]

Originally Posted by erooMynohtnA

I don't take issue with your conclusion, just the way you got there.

The moment of inertia changes (at least if you use the blade for the axis of rotation). The balance changes. The center of gravity changes.

By the argument you use against a change in center of graviy, I could bend a foil in half and stick the handle on the tip end, and the center of gravity would still be the same, because there has been no change in mass. A center of gravity is not simply how massive an object is, it is fully dependent on the distribution of that mass. By that same argument, the children on the seesaw would never move because the mass didn't change, and the wire that Inquartata bent wouldn't have moved. Also, there is a change in mass, not the overall mass, but where that mass is placed, and that's all it takes. If you change the shape of something, you generally change where the center of it is.

Also, the moment of inertia is based in mass as well. It's angular mass. It is how the mass in the object reacts to angular forces (or torque if you will). You have to define the axis about which the weapon is to rotate, and from there you get the moment of inertia which is a number denoting the resistance to movement in kilogram meters squared (meters is squared not kilograms). The number can either get bigger or smaller. The moment of inertia is a highly specialized phrase, and it does not "shift," because there is a defined axis for any moment. Although, a center of gravity (or mass) does because it is a point in space, not a number. You can change the moment of inertia for an object drastically by simply changing the axis about which it rotates.

However, I also believe all these changes are small enough to the point of being negligible, which is the way to argue it. Not that it simply doesn't happen and to eschew the physics describing it and how negligible it is.

You're firing from the hip with physics terms, and it's not helping anything. I do believe that you're correct that stronger muscle groups are utilized when a blade is canted. But, I don't think an argument rooted in faulty physics is the way to prove it.

i agree, never claimed to be a physicist. are you? i'm an engineer, so for me, negligible is the same as nonexistant

i could've sworn, though, that you couldn't cant the blade enough to cause the center of gravity to change, unless your cant is rediculously illegal. we're not talking about putting a >=90 degree bend on the blade, here.