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Vincent Le Chevalier




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PostPosted: Thu 26 Jul, 2007 2:41 pm    Post subject:         Reply with quote

Angus Trim wrote:
This kind of stuff happens in cycles. When the online community first "started", we had discussions of this nature, and decent swords were often knocked as "wrist breakers". Later, when folks were educated about dynamic balance, cog wasn't as big a deal...... but then some of the old timers "moved on", and we started all over with new folks doing the same song as three years previously........
And again......
And again.......
The educational process is a never ending process........... And at the same time, the makers evolve and change to the market............


I think part of the problem is that no definitive conclusion ever appeared on the subject of dynamic balance (and possibly on harmonics either). Beginners cannot be expected to read and make a synthesis out of the thousands posts here and on many other forums overnight... So they will have questions raising from the common knowledge: there is a point named point of balance that everyone is talking about and is described in several articles (it's in the features of myArmoury) as well as a host of other points and nodes that experts seem to care about, but nothing that explains how they interplay, what they impact, how they can be adjusted, the consequences on handling, the value they can have or should have, etc. Over the few years I've been reading forums here, it seems to be the bulk of the questions asked. The fact is that I don't know of any article that goes so deep...

Angus, you said once that this relative fuzziness remains partly because the subject became quite controversial years ago, and so people are basically walking on eggs about this now. I think it's also because to conduct such an analysis it takes three things: familiarity with sword handling (at least a basic idea through discussions with martial artists), access to a fair number of originals that can be handled, and familiarity with the math and physics needed to explain and predict the behavior. How many people out there have these three things, I honestly don't know. I definitely miss the second, that's sure Sad So the matter is inherently hard, and such things do not solve themselves quickly.

Hopefully discussions like we had here can help with the exchange of the necessary information...

And of course I'm not blaming anyone for that lack of conclusion, or articles. I started trying to sum up what I think I know and understand more than a year ago, and that task is really hard Eek! And I doubt that what I'm trying to do will ever become the work of reference I would have liked to find at the beginning...

Well, I'll still have to try, if just to see how it fails Wink

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Angus Trim




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PostPosted: Thu 26 Jul, 2007 3:10 pm    Post subject:         Reply with quote

Hello Vincent

The, uhh, controversy seems to be fading the last year or so......

Yeah, it got politicized for a while. Egos got involved, business interfered, but I'd say that things have kind of settled out since things were "hot".......

The thing is, we make some of this to complicated. Its not rocket science, really not.

Saying that however, there is an experience factor, and a way of relating to the universe factor. {I can't express it any better at the moment}. Some of this makes sense easily for some of us, and some of it is nonsense for many others......

Lets take distal taper, and relate this back to this conversation. Distal taper in my mind, is the easiest, most obvious way to control the distribution of mass, and how things come out on the finished sword. But its worthless if it doesn't work well with the rest of the factors that make up a sword, or make up "the distribution of mass".......

One of the things the last four years or so, is how secretive distal taper is done by some parties. Then someone will come up and say "The AT1312 I have handles just like the Albion Knight I have"....... Funny thing that.....

Then someone else will try and make a XII, and its too floppy, or too heavy, or whatever....doesn't work........

The words that are written on the function of the sword, can be educational, but in something so small as a thread, or an article, even the best do not leave enough info to help someone not already making swords, to make good swords. Too much left out, even when there's no intent to so.......

To try and bring this back to center of gravity...... I look at the center of gravity as a symptom, not a function. Its something you can see and measure.... but its not all that telling in the function of a sword...... and I think its a worthless measurment when talking about "typical".......

Its a statistic people want to see. And since much of what we do is on the internet, it probably has some value..... its not like we can walk up to a stall on a street corner, and handle several.......

swords are fun
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Nathan Robinson
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PostPosted: Thu 26 Jul, 2007 4:22 pm    Post subject:         Reply with quote

Peter Johnsson wrote:
It is like picking a typical Swede and a typical American and from the number of possibilities end up with me and Gus Trim.
We are both pretty typical examples of "Swede" and "American". The value of using us as Types depend on how you apply and interpret the principle.


Gus is far from being a typical American Happy Razz

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Bryce Felperin




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PostPosted: Thu 26 Jul, 2007 6:22 pm    Post subject:         Reply with quote

Vincent Le Chevalier wrote:
Angus Trim wrote:
This kind of stuff happens in cycles. When the online community first "started", we had discussions of this nature, and decent swords were often knocked as "wrist breakers". Later, when folks were educated about dynamic balance, cog wasn't as big a deal...... but then some of the old timers "moved on", and we started all over with new folks doing the same song as three years previously........
And again......
And again.......
The educational process is a never ending process........... And at the same time, the makers evolve and change to the market............


I think part of the problem is that no definitive conclusion ever appeared on the subject of dynamic balance (and possibly on harmonics either). Beginners cannot be expected to read and make a synthesis out of the thousands posts here and on many other forums overnight... So they will have questions raising from the common knowledge: there is a point named point of balance that everyone is talking about and is described in several articles (it's in the features of myArmoury) as well as a host of other points and nodes that experts seem to care about, but nothing that explains how they interplay, what they impact, how they can be adjusted, the consequences on handling, the value they can have or should have, etc. Over the few years I've been reading forums here, it seems to be the bulk of the questions asked. The fact is that I don't know of any article that goes so deep...

Angus, you said once that this relative fuzziness remains partly because the subject became quite controversial years ago, and so people are basically walking on eggs about this now. I think it's also because to conduct such an analysis it takes three things: familiarity with sword handling (at least a basic idea through discussions with martial artists), access to a fair number of originals that can be handled, and familiarity with the math and physics needed to explain and predict the behavior. How many people out there have these three things, I honestly don't know. I definitely miss the second, that's sure Sad So the matter is inherently hard, and such things do not solve themselves quickly.

Hopefully discussions like we had here can help with the exchange of the necessary information...

And of course I'm not blaming anyone for that lack of conclusion, or articles. I started trying to sum up what I think I know and understand more than a year ago, and that task is really hard Eek! And I doubt that what I'm trying to do will ever become the work of reference I would have liked to find at the beginning...

Well, I'll still have to try, if just to see how it fails Wink


There is nothing unique about any of this. For other examples of other industries and products where "feature fuzziness" reigns supreme you have horsepower/engine size in cars, chip speed in semi-conductors, calorie intake in soft drinks and coverage area for cell phones. It's all worthless information for forming an accurate and definitive value or impression of the product though. In any complex system or product there are a myrid variety of factors that all impact on how a particular system or product functions, and whether or not it functions better than any other product of similar use.

Unfortunately we live in a modern market driven society that likes to attach simple solutions to complex problems, that values simplistic and brief information summaries over concise and detailed information flow, and who likes to form quick impressions. Because of this we tend settle for brief and simple metrics such as "point of balance" to determine a product's worth and value because we don't always know or have time to research the detailed information. When we do research it, we are often forced to form a conclusion without actually having all the facts available to us.

I suspect that if you lived in a medieval society where time considerations flowed a lot slower, and where the variety and availability of new products was limited, you would have a different view on the value of all the competitive products and services around you. Instead you'd know how a good sword handled because you'd handled a lot of them and knew from experience what you wanted. Then you'd wait a long time before it's construction was finished. ;-)

In our modern society we purchase a finished product through the internet or acquire it at a faire or store without ever knowing how competing products would stack up "in the hand" or worn or used. In many cases we use a product or item for the first time and know no better on how to acquire a better one, or if a better one exists. Instead we rely on modern marketing and sales pitches to provide us information about the products we wish to buy and HOPE the information provided is both correct and accurate for us to make a careful evaluation. Often it is not, but we at some level accept this and instead attach our decision buying process to terms such as "battle ready" or "point of balance" to make our judgements.

Ah for the old days...


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Angus Trim




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PostPosted: Thu 26 Jul, 2007 9:12 pm    Post subject:         Reply with quote

Nathan Robinson wrote:
Peter Johnsson wrote:
It is like picking a typical Swede and a typical American and from the number of possibilities end up with me and Gus Trim.
We are both pretty typical examples of "Swede" and "American". The value of using us as Types depend on how you apply and interpret the principle.


Gus is far from being a typical American Happy Razz


Nathan's right..... a terrible combination of characteristics one would hope most Americans don't have......

Not very bright, terrible, explosive temper, and oversize ego..........

swords are fun
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PostPosted: Thu 26 Jul, 2007 9:29 pm    Post subject:         Reply with quote

Bryce Felperin wrote:


Unfortunately we live in a modern market driven society that likes to attach simple solutions to complex problems, that values simplistic and brief information summaries over concise and detailed information flow, and who likes to form quick impressions. Because of this we tend settle for brief and simple metrics such as "point of balance" to determine a product's worth and value because we don't always know or have time to research the detailed information. When we do research it, we are often forced to form a conclusion without actually having all the facts available to us.

Ah for the old days...


Bryce Felperin


Swords really aren't rocket science, so this really is a simple solution, to a simple problem. The real problem comes up when these discussions take place, because they take place in dry text, which doesn't allow some of us to communicate as effectively as we could over a beer.....

There was a sword industry before the internet. There were sword enthusiasts before the internet brought us together, and Oakeshott wrote his typology long before the internet came along......

However, the internet revolutionized much of the market. The internet "made", Angus Trim, Peter Johnsson, and Albion. Tinker was a local SCA and RenFaire swordmaker. Arms and Armor an obscure Minnesota arms maker. Practically overnite, we went from Del Tin {being marketed by Museum Replicas} being "the quality sword", to a vast array of reasonably good swords. Antiques were discussed, and specs sent from one to another across the Atlantic. The "mechanical" aspects of a sword, the functional stuff was discussed, and the whole industry improved. The interaction between swordmakers and both sword enthusiasts and martial artists became a part of the marketplace, and a part of the finished product........

Then we come to the center of gravity question....*g* PJ answered the thing on typical as well as it can be answered....

swords are fun
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Vincent Le Chevalier




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PostPosted: Fri 27 Jul, 2007 1:41 am    Post subject:         Reply with quote

Angus Trim wrote:
Swords really aren't rocket science, so this really is a simple solution, to a simple problem. The real problem comes up when these discussions take place, because they take place in dry text, which doesn't allow some of us to communicate as effectively as we could over a beer.....


On the other hand, sometimes one should be wary of conclusions drawn over several beers Wink

I agree with Gus when he says that it's not rocket science; I mean, swords are still way simpler than cars as a physical system. No engine, no mobile parts... They are even closer to being mono-dimensional (as in, all the mass is roughly on the same line). We ought to be able to measure and compare them at distance a lot more precisely...

Of course Bryce, this problem did not really exist in medieval time. It's just that now, swords are a lot more rare... So the way we can communicate about them becomes important.

I know there is fear that measures can be used as marketing tools, but really it should not be the case. If they have a clear interpretation, and are easy to make, I don't think any seller would benefit from falsifying them. Would be too easy to notice...

The problem right now is that we have two sets of caracteristics. There are some aimed at users (CoG for example), that have been found severely lacking (as in, two swords vastly different in handling can have the same CoG). There are some that are essentially manufacturers tools (distal and profile taper come to mind), that do not easily translate to handling either, but describe the technical means for achieving the desired properties.

Measures in the second set are in general too complex to be of any use to someone that is not a swordsmith. Measures in the first set are more global and synthetic, the only work needed is expanding them to make them actually significant... The knowledge to do that is, in my opinion, already out there. But it is spread over a vast number of forum posts, part of discussions where the ideas were debated, with many prerequisites, a few articles (old ones, in general) and perhaps physics textbook. And this knowledge is still largely untested, because we lack published significant measures. Of course, since we still have to agree as to what is significant Wink

Actually, I wonder if I will not start another thread to compile precise links to all the info hidden here and there, and quotations that I find significant... A sort of "press review" of balance. Could come in handy in threads like this... Would not replace a comprehensive article, though.

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J.D. Crawford




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PostPosted: Fri 27 Jul, 2007 5:20 am    Post subject:         Reply with quote

One thing that occurred to me overnight is that our physical training is presumably quite different from that of the medieval or pre-medieval warrior. Most of these people were not just swordsmen - they were just as likely or more likely to be used to the use of weapons like the axe, mace, or war-hammer that placed the mass and PoB/CoG way out from the hand. I have not tried this myself (perhaps people in the reenactment community have) but one can easily imagine that if your muscles are trained to swing an axe, then a sword with a 7" PoB would have to feel pretty nimble by comparison.

-----------------------

From a scientific point of view (sorry, that's my day job) swords are not that complicated when viewed in isolation - they are essentially rigid bodies that are capable of rotating and translating through space. But it gets hellishly complicated to describe the kinematics and dynamics of sword control once you attach them to a hand and have them moving through space in an gravitational/internial system.

The PoB comes into play for producing both types of movement (rotation and translation)....if you want to translate the blade through space by applying a force, the the farther this force is placed from the PoB then the more counter-rotation you will produce due to the intertia of the material on the oppostie side. So you have to produce a slight counter-torque to keep the blade from rotating.

If you want to rotate the blade, you need to apply a torque to overcome the rotational intertia and forces of gravity acting on the blade. Again, the fruther the hand is from the PoB, the more gravity is going to produce a 'helping' or 'hindering' effect in a direction-dependent manner. But that's not the only problem - even if your hand is right on the PoB, then the inertial of the blade will resist rotation depending on the distribution of mass about that point. So, let's say you make a war sword with a long handle and big pommel so that the PoB is right in your hand, its still going to feel sluggish due to all that mass way out there.

Most sword moves involve both rotation and translation , and this relates back to biomechanics. Joints only rotate, but they can translate the hand becaus the muscles apply torques about them and they are linked through rigid bodies (the arm bones). As one goes to rotations at the wrist, the elbow, to shoulder, there's a gradient of going from more sword rotation to more sword translation, because the biomechanical point of rotation is getting further from the sword, but the muscles are also getting stronger. Wrist rotation will give the fastest sword rotation, but the wrist is also weaker. For these various reasons, for a given weight, a sword with a 'good' PoB and mass distribution seems easier to swing with the wrist, whereas its easier to swing with the shoulder in the opposite case. (I'm not even touching on balance, posture, vision etc - and worse yet,, the muscles, nerves, and brain structures that control all this).

Then there's the cost-benefit function between 'handle-ability' and damage produced, which depends on a whole other set of physical factors that I won't get into here. I have heard it said that velocity is more important than mass, and this is true in a sense, but only within limitations. Muscles can only contract so fast. There's a reasons why its easier to chop down a tree with an axe than a rapier, even if the rapier didn't break.

I have been glancing at this site for years, and I know that many of you have considered these factors, just using a different language than we would use. But when it comes to complicated - yeash...take it from someone who has spent the last 20 years trying to understand simple things like eye rotation and pointing, the science of sword control is way more complicated than rocket science. We have rockets, but we don't have robots that can fence. Assuming there was funding for such a thing, I bet I could put an army of PhD students on this topic and they wouldn't solve it in 100 years.

I think my cold is getting better... time to get back to work.
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Bryce Felperin




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PostPosted: Fri 27 Jul, 2007 11:43 am    Post subject:         Reply with quote

Well one way of dispelling a marketing metric that doesn't work is to create a new one. :-) So perhaps we, as a community, can come up with another type of marketing rating, and quantify it, when someone else mentions a sword's POB.

Otherwise POB will continue to be used by laymen and others as a metric, despite its inaccuracy. Maybe a use oriented a number to reflect a sword's preferencial use for either thrusting or cutting. Maybe a mathematical formula could be used to generate a number based upon several factors in a sword's construction, such as weight, POB, node placement and distel taper degree.

People will always try to create a metric to better understand things they can't conceptualize. As knowledgeable people in the study of swords though it should be our job to come up with metaphors, information and ideas that can better express to other people the whole idea of what makes a sword a good sword. Perhaps some of you in the industry who produce them could come up with a metric, or series of metrics, that common consumers can grasp and use in place of POB.

Just my two cents of thought...
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Vincent Le Chevalier




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PostPosted: Fri 27 Jul, 2007 4:22 pm    Post subject:         Reply with quote

J.D.,

J.D. Crawford wrote:
From a scientific point of view (sorry, that's my day job) swords are not that complicated when viewed in isolation - they are essentially rigid bodies that are capable of rotating and translating through space. But it gets hellishly complicated to describe the kinematics and dynamics of sword control once you attach them to a hand and have them moving through space in an gravitational/internial system.
[snip]


Of course you are right, but here the complexity does not lie in the sword, rather in the user. Fencing is immensely complex to model mathematically because the moves and reactions of the human body are hard to model and understand, sword making is immensely complex because of the craftmanship involved. However, the sword in itself (and most hand-held impact or cutting weapons) is really a simple object dynamically, that enhances our capacity and complex motions. Simple and effective, that's the beauty of the thing. I suspect that if we had boxing robots, it wouldn't be so difficult to make them fence.

As you said swords could be considered as solid bodies, and I tend to view them as 1D as far as mass distribution is concerned, so in effect what do we need? Mass, inertia, positions of both ends with respect to the CoG, and that's about it for the sword itself... Next thing you need is an idea of how the forces are applied to the weapon, and I think that it is already quite precise to consider that they can be applied at two spots (both ends of the handle). So we are looking at what, more or less 6 independent parameters? I stand by the fact that it is quite simpler than a rocket Happy

Now, finding how to combine these to get stats that are intuitively linked to handling is the hard part. But it cannot add complexity... At worst it will always be 6 numbers. Either that or the stats will have relations between each others.

While I'm there, I'll react to Bryce's observation, that are really spot-on:

Bryce Felperin wrote:
People will always try to create a metric to better understand things they can't conceptualize. As knowledgeable people in the study of swords though it should be our job to come up with metaphors, information and ideas that can better express to other people the whole idea of what makes a sword a good sword. Perhaps some of you in the industry who produce them could come up with a metric, or series of metrics, that common consumers can grasp and use in place of POB.


I did propose such metrics in this post. It's exactly the kind of combination leading to more intuitive stats that I was referring to above. Truth to be told, I have changed the set a bit, but I kept the basic ideas...

Problem is, given that I'm neither a famous swordsmith, nor an accomplished martial artist, nor a respected scholar of the sword, I clearly lack the credibility to set an industrial standard Wink


Since the thread is about the PoB, I should point out that the fourth stat I describe in the post above (what I call "blade mass" for lack of a better term) is a very satisfying way to link the PoB's position to the handling. A pivot point is needed, but the benefits are clear.

Here is a little experiment that I find enlightening about the PoB. If I take one of my hammers and my rapier in a fist grip (not proper for use, but it's for the sake of the demonstration), both center of balance end up at the same distance from my lead finger (approx. 4.3in). Does that make my hammer a proper rapier? Certainly not. It's not even a question of length, the difference in balance can be felt without opening the eyes...

In that case, my stat for "blade mass" would give a result close to 1 for the hammer (nearly all the mass in the head), but less than 0.1 for the rapier (much of the mass is in the hilt). Of course there are other differences, but that's already something significant and intuitive, I think...

Best,

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Craig Johnson
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PostPosted: Fri 27 Jul, 2007 4:33 pm    Post subject:         Reply with quote

Angus Trim wrote:
Nathan Robinson wrote:
Peter Johnsson wrote:
It is like picking a typical Swede and a typical American and from the number of possibilities end up with me and Gus Trim.
We are both pretty typical examples of "Swede" and "American". The value of using us as Types depend on how you apply and interpret the principle.


Gus is far from being a typical American Happy Razz


Nathan's right..... a terrible combination of characteristics one would hope most Americans don't have......

Not very bright, terrible, explosive temper, and oversize ego..........


Gus

You forgot damn cute!

Craig
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PostPosted: Fri 27 Jul, 2007 5:41 pm    Post subject:         Reply with quote

Vincent Le Chevalier wrote:


Problem is, given that I'm neither a famous swordsmith, nor an accomplished martial artist, nor a respected scholar of the sword, I clearly lack the credibility to set an industrial standard Wink


,


Its been done once, though it didn't "stick". Don Nelson did the statistical thing, and came up with a numerical grading system measuring "heft" that some folks really liked. Josh Hemingway thought enough of it that he started posting the number when he put up a new sword on AllSaints, when it was his......

He {Don Nelson} upgraded it once, when more info became available.....

It didn't long survive his death. There's still record of it though, if someone were to dig back about three to four years back on SFI.......

Point being, is you likely will have some of us swordmaking types pointing out weakness' of what you come up with, but if overall it works for most, you just might set an industrial standard.....

swords are fun
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Vincent Le Chevalier




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PostPosted: Sat 28 Jul, 2007 3:31 am    Post subject:         Reply with quote

Angus Trim wrote:
Vincent Le Chevalier wrote:

Problem is, given that I'm neither a famous swordsmith, nor an accomplished martial artist, nor a respected scholar of the sword, I clearly lack the credibility to set an industrial standard Wink

Its been done once, though it didn't "stick". Don Nelson did the statistical thing, and came up with a numerical grading system measuring "heft" that some folks really liked. Josh Hemingway thought enough of it that he started posting the number when he put up a new sword on AllSaints, when it was his......


Hey Gus, thanks for the pointer. I'll be sure to include a discussion of that if I get to do this "press review" I was thinking about...

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PostPosted: Sun 29 Jul, 2007 7:04 am    Post subject:         Reply with quote

Vincent Le Chevalier wrote:
J.D.,
Now, finding how to combine these to get stats that are intuitively linked to handling is the hard part. But it cannot add complexity... At worst it will always be 6 numbers. Either that or the stats will have relations between each others.
Best,


One needs 6 numbers just to describe the 3-D orientation and 3-D position of a completely rigid body in space...anyway, we can agree that things get very complicated once the sword is in use.

To get back to PoB/CoG and its relationships, I'm not sure if the relationship between this and pivot point has been discussed around here (probably has, and I've missed it). I stated above that if one wants to move a sword laterally without rotation, one needs to counteract the intertia that will tend to counterroate the blade. On the other hand, often one does not want to do this but rather let the sword rotate on its own...i.e, about the pivot point. If the hand is right on the PoB - no pivot point. So the pivot point is also a function of the distance of the hand from PoB, as well as mass distribution issues.

In the jargon of 'motor control', when one learns to use a sword, and any one sword in particular, one is developing an 'internal model' of the system. So if one has developed an internal model of a sword with a 3.5" PoB (plus all those other measures that are important) , then a sword with a 7" PoB is going to feel weird and wrong.

When I teach this subject to grad students I like to use real world examples...it would be fun to do a whole course using swordmanship as the example. Fun for me anyway...the students might start rolling their eyes after a while.
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Vincent Le Chevalier




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PostPosted: Sun 29 Jul, 2007 12:18 pm    Post subject:         Reply with quote

J.D. Crawford wrote:
One needs 6 numbers just to describe the 3-D orientation and 3-D position of a completely rigid body in space...anyway, we can agree that things get very complicated once the sword is in use.

Absolutely, but I was talking of the properties inherent to the sword (mass distribution), not to its motion. Something that does not change when the sword moves... But yes, I think we are on the same line.

J.D. Crawford wrote:
To get back to PoB/CoG and its relationships, I'm not sure if the relationship between this and pivot point has been discussed around here (probably has, and I've missed it).
[...]
If the hand is right on the PoB - no pivot point. So the pivot point is also a function of the distance of the hand from PoB, as well as mass distribution issues.


It has indeed been discussed, and the relationship is quite simple. If you have a reference point R where force is applied, and if G is the center of gravity of the sword, then you can find P, the pivot point associated to R, with the relation: RG * GP = J/M, where J is the moment of inertia of the sword around G, and M the mass. When a force is applied, the sword accelerates in rotation around P. Thus many of the effects you describe.

This is why I feel that pivot points are actually more relevant than CoG for handling. Or rather that CoG without pivot points does not mean anything, because it gives only a faint idea of the distribution of mass.

J.D. Crawford wrote:
In the jargon of 'motor control', when one learns to use a sword, and any one sword in particular, one is developing an 'internal model' of the system. So if one has developed an internal model of a sword with a 3.5" PoB (plus all those other measures that are important) , then a sword with a 7" PoB is going to feel weird and wrong.


This is also true, and nicely described. I think this internal model is what would give us the most precise insights as to which stat is important. But I have no idea how one could find it (the way the brain works remains quite mysterious)...

Regards

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PostPosted: Sun 29 Jul, 2007 8:17 pm    Post subject:         Reply with quote

Wow, and I thought the thread ended when I was told to search the forum for other threads. I wish I had been paying more attention to this thread in the last few days.

I do wonder though, is there not any average whatsoever? I would have though that the PoB would be within some general parameters (ex. not below the hilt and not beyond halfway up the blade). I also wonder if certain schools or traditions have anything to say about ideal mass distribution. Or was it a completely personal decision of the user?
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Lafayette C Curtis




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PostPosted: Sun 29 Jul, 2007 9:26 pm    Post subject:         Reply with quote

Sam N. wrote:
I do wonder though, is there not any average whatsoever? I would have though that the PoB would be within some general parameters (ex. not below the hilt and not beyond halfway up the blade).


Remember that "within some general parameters" does not always equate to the existence of an average balance point for the sword type in question. The sword type could have a range of plausible balance-point location without having a single point that can be designated as an "average" within that range.
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Vincent Le Chevalier




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PostPosted: Sun 29 Jul, 2007 11:38 pm    Post subject:         Reply with quote

Sam N. wrote:
I do wonder though, is there not any average whatsoever? I would have though that the PoB would be within some general parameters (ex. not below the hilt and not beyond halfway up the blade).


For a given type of sword, such a range can exist indeed. Problem is to get enough examples of the type to measure, though...

But the fact that a range exists does not automatically make the average significant, as Lafayette said. Imagine that for some reasons, within your type of word there are 2 values for the CoG that are more likely to be chosen than any other (I'm not saying it's the case, it's just an example). So the values are grouped around 2 points. If you make a crude arithmetic average, you will get a balance point somewhere in between, that is never chosen for your type of sword...

Note that there are statistical methods to deal with that. But then even if you find one or more representative balance point, it does not settle the question of what the rest of the properties of the sword should be, in relation to this average.

Sam N. wrote:
I also wonder if certain schools or traditions have anything to say about ideal mass distribution. Or was it a completely personal decision of the user?


There is not much about that, as far as I know. About dimensions of swords, there is plenty, but about balance... The only pointer I can give you is this recent thread on Tom Leoni's forums. It gives you an advice on the weight of different components of rapiers, supposedly written by Capoferro.

I think the reason why there is so little advice is that fencing methods are relatively independent from balance. As long as the sword is well-made and balance is acceptable (which was probably the case in period), you can fence.

Balance gives you an element of comfort and ease when it is adapted to the fencing technique you use. But it takes a really wrong balance to prevent you from fencing the way you want.

It is more crucial nowadays because we are trying to not only learn to fence but reconstruct the method. A weapon's balance gives it preferential moves, and we must be sure that we are not influenced by them, or better yet, that they fit the technique we want to reconstruct. A problem they did not have in the old days, probably.

Oh, if you need further info on the whole balance subject, I made a list of all the articles and threads that I found most interesting here:
http://www.myArmoury.com/talk/viewtopic.php?t=10758
Maybe some of these did not come up in your searches...

Regards,

--
Vincent
Ensis Sub Caelo
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Jeffrey Hull




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PostPosted: Tue 31 Jul, 2007 9:06 am    Post subject: Craftsmanship - Quality - Replication         Reply with quote

Angus Trim wrote:
The internet "made", Angus Trim, Peter Johnsson, and Albion.


Maybe you should speak for yourself.

It seems to me that excellent craftsmanship, high quality, and historically accurate replication "made" Peter Johnsson and Albion, or for that matter, Craig Johnson and Arms & Armor. Although those two craftsmen have a notable presence on the Web, some excellent swordsmiths like Paul Champagne have almost zero presence. When it comes down to it, it is the Work and not the Web that makes the difference.

JH

Knightly Dueling - the Fighting Arts of German Chivalry
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Chad Arnow
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PostPosted: Tue 31 Jul, 2007 9:48 am    Post subject: Re: Craftsmanship - Quality - Replication         Reply with quote

Jeffrey Hull wrote:

Maybe you should speak for yourself.

It seems to me that excellent craftsmanship, high quality, and historically accurate replication "made" Peter Johnsson and Albion, or for that matter, Craig Johnson and Arms & Armor. Although those two craftsmen have a notable presence on the Web, some excellent swordsmiths like Paul Champagne have almost zero presence. When it comes down to it, it is the Work and not the Web that makes the difference.


Maybe you should drop the hostility in your tone.

I think the internet has had a huge effect on the sword market. I'm not sure Albion would have progressed much beyond a retailer and simple customizer if not for the net. Peter probably wouldn't have been introduced to them or to us through Bjorn Hellqvist's presence in net communities, so we'd have no Next Gen or Museum Line. Peter's rise to fame and impact on this community would have been different without the net. He would still be a great sword-maker and still be doing more hands-on documentation of originals than most anyone else, but only a select few would know about him without the 'net. Gus might never have gotten into sword making if not for he and Tinker collaborating on Tinker's net-driven attempt to get into the production business, etc.

Gus didn't include A&A in his list, Jeffrey, because they existed before the net was widely used and so much of their business still comes through non-net sources (faires, etc.). Paul Champagne and others existed before the explosion of the net and had good customer bases in place already. Some other business, though, exist completely (or at least to a large extent) because of the internet.

At one point, the vast majority of Albion's business was through (or because of) the net. I'd suspect the same is/was true for Gus. Albion is trying to branch out to meet more non-net people; hence all the shows they go to now.

Quality counts for a lot, but it's undeniable that the 'net has made a huge impact on this community and has created business or made some grow way beyond what they were.

Happy

ChadA

http://chadarnow.com/
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