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Post by rammstein on Dec 22, 2007 17:27:28 GMT
Karma for you. I learned something new today.
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Post by Deleted on Dec 22, 2007 18:06:24 GMT
...Shootermike, I may be wrong, but the pivot point you find in your video just happens to look like(to me anyway) the halfway point between tip and grip of your sword. Based on the movement you use to demonstrate it, it would appear to be the same on all swords, regardless of harmonic balance. After looking at the video, I see that impression. I measured the pivot point on this particular sword. The overall length of the sword, from tip to pommel nut is 38.25 inches. The pivot point I feel when rotating the sword is just over 21 inches from the pommel nut. Leaving about 17.25 inches of blade tip in front of the pivot point. I don't care for that handling at all. So for the sake of experimentation, I replaced the Darkwood rapier guard with the original straight cross guard. The original guard weighs barely a third the weight of the rapier guard. This change moved the pivot point back to 15.5 inches from the pommel nut. Leaving 22.75 inches of blade tip ahead of the pivot point. MUCH BETTER! It has a lot more perceived "reach" from the same length blade. Looks like I kind of screwed up this sword by adding the rapier guard. It looks cool. But the performance in the cut has been severely degraded. With the original guard on, it looks funny with 2.5 inches of skinny ricasso in front of a simple cross guard. But at least it has been a learning experience, huh? ![:-[](//storage.forums.net/forum/images/smiley/embarrassed.png) Not only the pommel, but the whole weight of the hilt assembly. But I think that's what you mean in any case? ![???](//storage.forums.net/forum/images/smiley/huh.png) ...And that, my friends, is the difference between a 500-1000 ATrim or Albion and a Gen2. Amen to that. Mike are you saying that with the lighter hilt components (so that now the balance point is moved further up toward the tip of the blade) the sword wanted to turn in more quickly?
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Post by ShooterMike on Dec 22, 2007 18:28:46 GMT
Mike are you saying that with the lighter hilt components (so that now the balance point is moved further up toward the tip of the blade) the sword wanted to turn in more quickly? It depends on what you mean by "quickly." I mean the pivot point moved noticeably closer to the hand. Thus the distance the hand moves to pivot the sword is shortened. So in theory, that should make the sword rotate quicker, right? However, the longer balance point makes the sword feel like it has a lot more blade presence. So it feels like it might swing just a tad slower. But I haven't been able to cut with it yet to find out. In any case, it should be a good experiment. I'm just glad I did all this with a $180 Lee Reeves Special instead of with something more expensive. ![;)](//storage.forums.net/forum/images/smiley/wink.png)
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Post by Deleted on Dec 22, 2007 19:59:28 GMT
Mike are you saying that with the lighter hilt components (so that now the balance point is moved further up toward the tip of the blade) the sword wanted to turn in more quickly? It depends on what you mean by "quickly." I mean the pivot point moved noticeably closer to the hand. Thus the distance the hand moves to pivot the sword is shortened. So in theory, that should make the sword rotate quicker, right? However, the longer balance point makes the sword feel like it has a lot more blade presence. So it feels like it might swing just a tad slower. But I haven't been able to cut with it yet to find out. In any case, it should be a good experiment. I'm just glad I did all this with a $180 Lee Reeves Special instead of with something more expensive. ![;)](//storage.forums.net/forum/images/smiley/wink.png) I would be interested in your impressions when you can test it.
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Post by Deleted on Dec 22, 2007 20:03:29 GMT
i think what tsafas talking about is a point along th axis of the blade to get the quillions around while holding the blade point toward your opponent... am i right? Correct. I spin those quillions to protect my hand, so I need a sword that spins very balanced with minimum torque as I rotate my wrist. This is important to my style of fighting, but most rapier styles assume some minimal hand protection from the hilt. The balance along the axis of the blade becomes less important. I've noticed that if I work around a certain point of these bastard swords that I can get a LOT faster than trying to muscle it from the handle using my wrists and forearms. That is correct. It also cuts your range. Have you seen my Point of Balance video? Keep in mind that working off the POB is an option. You don't have to use it throughout a whole fight and you should not. While still in range but further back, you can rest the sword on your shoulder and hide it by holding your shield up. You can generate a lot of power from back there and they won't see it coming from behind your shield. You can then do a combination sequence off the POB as you close in. ShooterMike can has explained other concepts like the COP (center of percussion) and nodes of vibration. He is more familiar with those concepts then me. I don't use them in my style of fighting. I need to go back and reread what he said for my own education's sake. From what I see in the videos, that information can really be used to make awesome cuts. When fighting, I am less concerned with the perfect cut and more concerned with landing a good enough cut. So I will make a tip cut, cut with forte or cut with the back edge depending on what openings present themselves and what my position is at the time. These will be debilitating but will not cut a limb off. Excellent video
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Post by Deleted on Dec 22, 2007 20:57:25 GMT
hmmmm....
I've been thinking a lot about this in my spare time, and I think I've made some progress in my understanding of this principle.
When you are "balancing" a sword to find the centre of gravity (or PoB), gravity is applying force all over the blade. The centre will depend on how mass is distributed. Mass that is further away from the PoB can have a greater impact due to "lever effects".
This means a few things:
1: The centre of gravity is not necessarily the centre of mass. By this I mean that if you were to cut the sword in half at the PoB, one half of the sword may weight more than the other. This is because of level effects. This MIGHT matter. When you are swinging a sword around, you aren't fighting gravity, you are fighting the sword's inertia - ie it's tendency to stay immobile if it's immobile, or to keep moving in the same direction it's already moving. Inertia is determined by mass. I will need to think more about this to see if this actually matters or not.
2: The pivot point and the PoB will not necessarily be the same. Why? It's because when you are balancing a blade, gravity acts evenly all over the sword. When you are swinging a sword around, suddenly you are applying force to it at a very specific point. Depending on where this point is, "lever action" will be different etc. This will result in a pivot point that may not be were the PoB is.
3: The weight of your hand matters. My instructor mentioned a while ago that wearing a gauntlet affects the balance of a sword. I didn't think too much about it then, but I just remembered it. When you are moving your sword around with your shoulder, elbow and wrist, you also have to move the hand that holds the sword. A hand weights what, half a pound? That has to matter somehow.
Wow, this is getting *really* complicated. I'm sitting beside the Christmas tree drinking cider, so I think I'll have to revisit this another time!
Ancalagon
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Post by Deleted on Dec 23, 2007 0:16:56 GMT
The weight of a gauntlet, if worn, only affects your swing, not the balance of the sword.
Other than that you are essentially correct.
Please note that the pivot point that i was talking about and the pivot point Mike and Tsafa are referring to are different things.
With regards to my previous explanation:
There is no single 'pivot point' on a sword - there are any number of them depending on where the impact is made on the sword when you cut something.
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Post by Deleted on Dec 23, 2007 2:55:55 GMT
I don't know who originally said this, but that is wrong as Adam stated. Aside from any wrist movement limitations, the gauntlet effectively becomes part of the sword hilt. If your gauntlet weight 2 lbs, you just added a 2 lb basket hilt to your sword. It will change the point of balance and all the crap, just like if you added a huge pommol. I know this for certain cause I have steel gauntlets and have done tests.
With heavy gauntlets you are forced to use a hammer grip too. Limits some options like using a slipped grip or doing a hand-snap. It can be hard to get a good sense of edge alignment.
It is not easy to use a single handed sword with gauntlets. Gloves with padding on the outside and mail over that are more functional. Even with a two handed sword, it is hard to used full gauntlets. You need 18 inch handles. Full gauntlets work best with polearms that have long handles.
I recently had a chance to look at the armor of Henry XVIII at the met. He had half gauntlets. Someone recently informed me that those half-gauntlets have holes on the side where mail would cover the fingers.
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Post by Deleted on Dec 23, 2007 4:26:47 GMT
I'd rather this not get into an argument, but...
I said the 'weight of the gauntlet' not the gauntlet itself - so movement and the restriction thereof are a completely different matter.
And no, it doesn't change the balance of the sword. The sword is still balanced the same, and still has the same harmonic. You'll feel it different cuz now there's steel inbetween the grip and your hand, but the sword still reacts in the same way to external forces.
Case in Point: If your dynamic pivot point for an impact point at the tip of your sword is too low, you feel a kick forward into your fingers regardless of whether you wear a glove or a gauntlet or go bare-handed. If the pivot point is too high, you feel it kick backward into your hand, again regardless of any gauntlet you may be wearing.
Now of course, the gauntlet may dampen this feeling, but it doesn't mean that the dynamic of the sword has changed at all.
Weight throughout the grip is very different from weight in the pommel. Did you completely ignore(again) my point that distribution of mass makes a difference between swords of the same weight and PoB? There's SO MUCH MORE to a sword than that, and to balance swords based on those criteria alone is just silly.
I've just decided i'm going to make some youtube videos demonstrating the difference between hitting something and cutting something. If you want to cut something a 'hand-snap' just won't do it unless you've got an overly sharp sword and an overly soft target.
Really? 18 Inch grip is NEEDED to fight with a two-handed sword? Well I guess we'd better go back to ALL the medieval meisters and tell them they were doing it wrong when they wrote the harnessfechten portions of their fechtbuchs, since virtually none of them show swords with grips that long...
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Post by Deleted on Dec 23, 2007 6:47:43 GMT
Trust me on this. When you wrap your hand around the sword, your hand become part of the sword. Its mass adds to the swords mass. If you have 2 lbs of steel around your hand, you just added that to the sword-base. Similar to a roll of quarters in your hand if punch someone. The mass of the quarters and the mass of your hand become one.
I know I won't convince you with words, you will have to do a gauntlet experiment yourself if you want to see for yourself. If you pick up a type X sword with a gauntlet and start spinning it around the balance point you will see that the balance point is no longer 5 inches down the hilt, it is 3 inches down the hilt. The pob has moved. I would put of a video for you if you think that would help you see this clearly. Do you have steel gauntlets? You will see you can not take a two-handed grip on a 10 inch handle and be effective. You have no choice but to half sword. Even if you are fighting someone who has no armor.
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Post by Deleted on Dec 23, 2007 7:15:12 GMT
I disagree with your base assumption.
If I hold a sword in hand and feel it's weight, then put a gauntlet on and hold the same sword, the weight of the sword is still the same - except now I have extra weight on my arm from the gauntlet - it still takes the same effort of the forearm - neither more nor less, to hold the blade in the same position.
The weight of the sword rests against your fingers which must support it - the weight of a gauntlet does not - the weight of a guantlet is supported by the shape of it being fitted to your hand and being strapped on. You don't need to hold it with your grip, you do need to hold a sword.
Because a gauntlet's weight is not directly applied as torque to the lever that is a blade it's not a significant factor in the balance of the sword at all.
It's an interesting theory, but a false one.
To reiterate: A guantlet on a hand and a sword in the hand are supported there in completely different and exclusive ways. You may feel it in your upper arms and shoulders more as they actually have to move the extra weight, but the forearm/gripping muscles do not. The only difference to those muscles is the friction between the articulated plates of the gauntlet - which is far too insignificant to make a difference.
Thank you - i am familiar with the concept of complementary inertia. Problem is you don't punch with a sword - you swing it. Since the motion of your hand/arm isn't directly that which makes contact(that'd be the edge near the tip) with your target it's not nearly the same principle.
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Post by Deleted on Dec 23, 2007 19:38:07 GMT
Because a gauntlet's weight is not directly applied as torque to the lever that is a blade it's not a significant factor in the balance of the sword at all. It's an interesting theory, but a false one. To reiterate: A guantlet on a hand and a sword in the hand are supported there in completely different and exclusive ways. You may feel it in your upper arms and shoulders more as they actually have to move the extra weight, but the forearm/gripping muscles do not. The only difference to those muscles is the friction between the articulated plates of the gauntlet - which is far too insignificant to make a difference. By effort of the forearm do you just mean how much effort it takes to grip the sword? Any movement of the sword requires movement of the gauntlet, and as such the system mass has gone up, affecting every aspect of cutting. (Even the simplest wrist cuts require you rotate the part of the gauntlet on the hand and that added mass and its distribution requires extra force/torque to achieve the same motion (velocity etc.) compared to barehanded swing of the sword. The things mentioned above are magnified a great deal when you try to move the blade in larger arcs, and I think from studying these motions, the hand moves a lot more like certain bare hand techniques (hooks, jabs etc.) than you credit. If anything there are additional wrist movements as well, which require you to overcome the moment that the glove portion of the gauntlet imposes to effectuate the motion. Certainly the impact has little in common with puglism, but the forces required and the overall motions of the hand, as well as the demanded velocities and accelerations are quite similar. In short, to achieve the same trajectories and speeds of the sword tip requires more force when wearing the gauntlet. What is "complementary inertia"? I would kindly ask again for your mathematical derivation of the pivot point you mentioned you would provide previously. It would certainly help me more precisely understand that discussion. Thanks
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Post by Deleted on Dec 24, 2007 0:08:50 GMT
The amount of weight in a gauntlet is so insignificant because of it's proximity to what you're moving. Remember, even big swords weight in at around 4-5 lbs at the high end of the scale. A three year old can lift 4 lbs. What makes them heavy is the fact that a lot of their mass exists at distances away from the fulcrum of your movement - i.e. your hand. 1) A gauntlet's weight is spread across and around your whole hand. 2) Because it's so close to your hand(literally almost part of your hand), its mass and the force due to inertia that it adds to that required to move the sword is negligible. 'Complimentary inertia' means exactly what it sounds like it means. The inertia of smaller somethings adding up to make a bigger something to affect a greater force then the individual inertias could do alone. I.E. the Knuckle-Duster principle. The problem here in comparing that to a sword swing is that your hand moves almost not at all when swinging a sword(Your arm does move more but we'll get to that in a moment) - it's the leveraging effect that accelerates the sword tip a great distance. A good cut with, say, a side-sword takes very very little momentum from your body at all, but still gets that tip going really fast - or rather just fast enough. With knuckledusters your fist becomes the 'tip of the sword' per se, and generally a punch is linear whereas a swordcut is rotational. The only thing that makes a punch circular is the continued addition of force to pull the inertia off it's natural straight-line motion(newton's first law). Also remember that if a gauntlet weighs in at two lbs, that's almost NOTHING. Your body weighs 164 lbs, or mine does anyway, and when done properly, my mass(at least a good portion of it) is behind the swordcut adding far more than a measly 2lbs. As for deriving pivot points - a mathematical relationship exists between the POI, the Dynamic Pivot Point, and the CoG. Once you know ONE such relationship, you can use information garnered from that to find all the others. Remember - for each potential point of impact, there is a unique Dynamic Pivot point - so there are an infinite number, technically. ![](http://img297.imageshack.us/img297/9991/pivotpointderivationpi6.gif) If you draw a line from the CoG to the Point of imact, and another one perpendicular to the sword that is the same length as is from the CoG to the Pivot point, and complete the resultant rectangle, you will find that said rectangle always has the same area, regardless of Pivot Point and POI location. So if you find one such pair, find the rectangle, get it's area, then you can 'work backwards'. I.e. 1) Find that rectangle's area. 2) Then Pick your desired Pivot point(which should be right under the fingers of your primary hand - be it pinky finger or index finger, that's your choice. 3) From the CoG, draw a line perpendicular to the sword that is as long as it is from the CoG to your desired Pivot Point. 4) That's one side of your rectangle. You must draw the other one long enough to make this rectangle's area match that of the first rectangle you found in step one - even if to do so would place that point beyond the tip of the sword and in an abstract purely mathematical field. The resultant point is where you want to hit with your sword to not feel shock in your hands. It's the 'sweet spot' so to speak. Ideally, it should be at the tip of your sword.
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Post by Deleted on Dec 24, 2007 3:46:39 GMT
I unfortunately am not able to check your math at this time...
That being said, there is two fundamental notions I want to address.
1: Your notion that the pivot point is dependent on impact is really confusting to me. It's like we aren't even talking about the same thing at all. The pivot point is a spot your sword "likes to rotate around" when you are swinging it, not when you hit something. It should therefore be point of impact independent - although you want a pivot point that helps you swing the sword effectively, leading to powerful cuts and blows.
2: 2 pounds is not "nothing". Some one handed swords weight barely more than that. If 2 pounds was "nothing" then moving them around should be a piece of cake since they weight "nothing" right?
Ancalagon
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Post by Deleted on Dec 24, 2007 10:26:05 GMT
Your observations deserve merit - allow me to clarify:
1) I mentioned a couple times that the pivot point I'm talking about is different than the one Tsafa/Shootermike seem to be describing. In scholarly sword-educated circles however, if you were to mention 'pivot points' it'd be taken as meaning what I've been describing - which is a largely related to dynamically balancing a sword to have sweet handling characteristics.
2) Knowing the spot that your sword 'likes to rotate around' doesn't seem to me to offer any martial benefit. It's easy to find this spot as well. Throw the sword like you would a tomahawk - there'll be a spot it'll rotate around. It's called the CoG. The reason the CoG doesn't seem to match up with the spot that Shootermike/Tsafa are referring to is because in their tests they're holding the sword in a tight grip that adds torque to blade and changes its rotational dynamic.
3) I meant 2 lbs of weight on your hand is a negligible addtion to any sword swing as any such swing should already take advantage of your body weight in accordance with proper body and skeletal alignment and hip rotation.
I hope this sheds some illumination on my arguments so far.
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Post by Deleted on Dec 24, 2007 10:27:38 GMT
Oh right. Pivot Points depending on impact points. Please read my previous post(I believe it's on page two of this thread) for more information - I detailed it all there; and there are more diagrams to look at.
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Post by Deleted on Dec 24, 2007 17:04:20 GMT
The amount of weight in a gauntlet is so insignificant because of it's proximity to what you're moving. Remember, even big swords weight in at around 4-5 lbs at the high end of the scale. A three year old can lift 4 lbs. What makes them heavy is the fact that a lot of their mass exists at distances away from the fulcrum of your movement - i.e. your hand. 1) A gauntlet's weight is spread across and around your whole hand. 2) Because it's so close to your hand(literally almost part of your hand), its mass and the force due to inertia that it adds to that required to move the sword is negligible. 'Complimentary inertia' means exactly what it sounds like it means. The inertia of smaller somethings adding up to make a bigger something to affect a greater force then the individual inertias could do alone. I.E. the Knuckle-Duster principle. The problem here in comparing that to a sword swing is that your hand moves almost not at all when swinging a sword(Your arm does move more but we'll get to that in a moment) - it's the leveraging effect that accelerates the sword tip a great distance. A good cut with, say, a side-sword takes very very little momentum from your body at all, but still gets that tip going really fast - or rather just fast enough. With knuckledusters your fist becomes the 'tip of the sword' per se, and generally a punch is linear whereas a swordcut is rotational. The only thing that makes a punch circular is the continued addition of force to pull the inertia off it's natural straight-line motion(newton's first law). Also remember that if a gauntlet weighs in at two lbs, that's almost NOTHING. Your body weighs 164 lbs, or mine does anyway, and when done properly, my mass(at least a good portion of it) is behind the swordcut adding far more than a measly 2lbs. As for deriving pivot points - a mathematical relationship exists between the POI, the Dynamic Pivot Point, and the CoG. Once you know ONE such relationship, you can use information garnered from that to find all the others. Remember - for each potential point of impact, there is a unique Dynamic Pivot point - so there are an infinite number, technically. If you draw a line from the CoG to the Point of imact, and another one perpendicular to the sword that is the same length as is from the CoG to the Pivot point, and complete the resultant rectangle, you will find that said rectangle always has the same area, regardless of Pivot Point and POI location. So if you find one such pair, find the rectangle, get it's area, then you can 'work backwards'. . Are you saying that if you took two identical swords and to one glued a gauntlet (so that your fingers could slip in) that you would find that the two swords negligibly different in handling? That is, you would be indifferent between a 4 lb sword and a 6 lb sword (the second having an extra 2 lbs distributed around the handle)? Thanks for the diagrams, I know what you are driving at now. (Though you should realize that this specific rectangle works only for prismatic homogeneous elements-i.e. objects of constant cross section and uniform density. For more complex things like swords, you need to calculate the principal moments, as they are not accurately described by length and width alone) The web site you took them from has a lot of additional information that will be interesting to read so thanks again.
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Post by Deleted on Dec 24, 2007 22:25:43 GMT
And a gauntlet glued to a sword is not that different from a basket hilt... and basket hilted sword are known for being lively due to their balance.
Ancalagon
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Post by Deleted on Dec 25, 2007 1:40:55 GMT
You're right, a gauntlet glued to a sword isn't that different from a basket hilt.
But it *IS* very different from a hand, wearing a gauntlet, holding a sword.
If you don't think that a sword moves within your grip and independent of the surface skin on your hand, then you're fooling yourself.
I have a basket hilt sword. A cold steel. It handles like crap. It weighs less than 3 lbs overall. It has a PoB of about 2 inches in front of the cross. There is, simply put, far too much mass in the blade; The basket hilt, though it does technically bring the PoB back - DOES NOT HELP THE HANDLING CHARACTERISTICS OF THE SWORD AT ALL!. Because the mass of the sword still lies in the blade. The basket's mass is too close to the fulcrum of the resultant lever created when holding the sword to effectively change the dead weight feeling. Now if the entire basket were fused into a solid piece, and that were made into a pommel, that make make a difference - though I have the feeling it'd still not be too great. The idea that baskets serve as pommels is absurd and caused by people whose understanding of sword dynamics tops out at things such as PoB and Overall Weight.
Geez people. Think.
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Post by rammstein on Dec 25, 2007 2:09:35 GMT
I'm with Adam once again. Don't forget, at gauntlet isn't moving the sword, the hand behind the gauntlet is. And most gauntlets are either lightly protected or completely unprotected leaving the palm exposed, so essentially all it is is a sword on a heavier than normal arm. The sword's balance itself remains the same as it was, but the effects of having a gauntlet on might influence other aspects. I'm not a math major, I'm a future history major, so I'll let Adam do the proving ;D
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