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Top Speed of a Fencing Weapon

  1. Aug 24, 2010 #1
    I apologize if this is not the correct subforum for this topic.

    There are several unsubstantiated claims of speed in fencing, including one on the United States Fencing Association's website. http://usfencing.org/resources/fencing-facts [Broken] (#3) This led to a long discussion in which this forum was referenced, and I was impressed with the knowledge displayed.

    I have heard several claims regarding the speed of the tip of a weapon. The first is that other than a bullet, it is the fastest thing in sport. Some people even claim to have heard a fencer's weapon break the sound barrier. Unfortunately, there is no evidence of how fast the tip goes, so all arguments break down into speculation. Are there any simple experiments (simpler than a high speed camera) or any thought experiments to go about confirming or disproving either claim? I have a list of the top speeds in other sports if anyone is interested.

    Another myth is less a myth than an assumption most people make about which weapon is the fastest. There are three weapons in fencing: foil, epee, and saber. Most people specialize in one and argue only its virtue. Many foilists argue that fastest action in fencing is a "flick" in foil, during which a fencer causes his blade to bend around another blade or to obscured target. I think most saber fencers assume saber is the fastest simply because it looks the fastest. The "chest cut" is largely agreed to be the fastest cut in saber, but some people believe it is when the blade hit the opponent's guard and "whips" over that the tip goes the fastest. Some things to note are that the foil is more flexible than a saber and is more tip-heavy. Sabers are more rigid, lighter at the tip, and better balanced. Most people don't consider epee in the running for top speed, and its blades are the heaviest and stiffest.

    If anyone has any questions, I will be more than happy to clarify.
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Aug 26, 2010 #2
    I guess one way to do it would be to measure how much force a fencer can generate with their respective weapon. That shouldnt be too hard to do, although I dont really know the exact apparatus you would need.

    Once you have that, you know the material properties of each blade, and can calculate the how it would react to the force ( how it would bend etc).

    Since you know the above, you could measure the speed (velocity) at which the tip or any other part of the blade oscillates (I'm guessing it would be some form of SHM) and its that SHM which would give you the maximum and minimum velocity of the blade.

    While you're doing this, the two cases that I can think of right now would be when a fencer stops the blade without hitting anything (ie naturally) and when the blade is blocked (forceful stoppage).

    Its probably during the forceful stoppage of the blade that you would get your all time max velocity as the blade would effectively become 'shorter' in that it would vibrate around the point of contact (of the two blades, if one blade blocks another) and the shorter length would lead to a higher frequency of vibration and thus higher velocity.

    As far as the specifics are concerned, I have no idea about fencing and the different properties of different blades. Hope this helps.
  4. Aug 26, 2010 #3


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    "There was a young fellow named Fisk
    Whose fencing was exceedingly brisk;
    So fast was his action
    The Lorentz contraction
    Reduced his rapier to a disk."
  5. Aug 26, 2010 #4
    Interestingly, my neighbor across the hall is a weapons expert, and he has a wall full of blades ranging from a 40-lb monster of a broadswoard to his blade of choice, which is the rapier for it's ridiculous lightening speed.

    As an individual interested in the martial arts, he and I took a trip to the local gym, where we discovered that while he could certainly dispatch me with a rapier, he could never escape death himself, except perhaps by those who know few/little/no martial arts.

    We also discovered something else. In accordance with the laws of my own state and 43 others here in the United States, I carry a firearm on a routine basis.* We also discovered that beyond about 15 feet, my firearm trounced his rapier, even if thrown. Yes, he may very well indeed pierce my heart, but I still have 10 seconds in which to pull the trigger on 17 rounds in my firearm.

    Bottom line: When two top-notch folks are lined up for the death, the decision goes to the one who decided not to show up in the first place, or to the own who instead decided to leverage today's technology to take out his oppononent by means of stealth.

    * I know many people in the UK might find this "offensive." Please understand your sociopolitic environment and mine are very different. It's nothing for me to eat breakfast in a crowded restaurant full of kids here in the US while wearing a firearm, and to be quite frank, neither the kids nore their parents think anything of it. In fact, on a couple of occasions they've asked questions which I've entertained with them and their parents. I might argue they're the safer for it, as my eye is on the bad guy (yes, I've been amply trained), and because of 20 years of military training, if the call to arms ever does come, I know I won't miss. Still, the sight of anyone wearing a firearm in your country would result in numerous calls to your police. I understand that. However, please do not confuse my posting my thoughts and experiences about this with actually carrying arms, as some knee-jerk reactionists on another forum have done.

    Thank you.

    I would also extend this to you: If you feel I am wrong on the subject, please let me know via PM why you feel so. Here in the US, open carry is allowed in 43 of our 50 states, and concealed carry is allowed in 48 (I think) of our states. I am not arguing for any cause in this thread, so please do not wrongly ascribe any such motives. If you'd like to take things up with me via PM, I will be happy to interact with you in that forum.
    Last edited: Aug 26, 2010
  6. Aug 26, 2010 #5
    My entire point is that with what I and my neighbor (and rapier expert) know of self defence, if I'm within about 20 feet of someone with a rapier, I'm either better off closing rapidly with my hands (assuming I'm an expert in martial arts, which I'm not) or retreating to the use of a firearm. As for me, I would drawn and block, but only fire if he hurled his rapier or other blade towards me.
  7. Aug 26, 2010 #6
    Interesting discussion! I've love to get my high-school chum online, who wound up being a fencing champion at a prestigious Virginia university. Sadly, he simply doesn't do this!

    I think it largely depends upon what you want to do. I mentioned the "rapier" earlier, but that's the guy across the hall. I think my HS chum favored the foil, and again, his reasoning was rapidity and precision of blade movement. In fact, I recall a 1983 quote from him: "It doesn't matter how well they parry. If I can pierce his heart, he's dead. All I have to do at that point is retreat while the dead man tries to defeat me."

    Yeah, I know, it's a long quote to remember, but he was a very gifted friend (and a 4.0 valedictorian of our HS).

    I tend to recall what he says.

    He's a doctor, now, I think. We lost touch.
  8. Aug 27, 2010 #7
    I don't think that simple harmonic motion would be the way to go to achieve maximum possible velocity. I've tried to create such a situation, and any speed I achieve has always been far surpassed by a simple slashing motion. I don't know if it's a problem with forearm strength, blade flexibility, or inability to change direction quickly enough, but I am 99% sure it would be impossible for all other people, too.

    I have found a motion resembling a tennis serve or badminton smash seems the fastest to me.

    There's a thing called "whipover." That happens when the end of your opponent's blade hits your guard and the last foot or so bends over your guard and hits you on your arm. Do you think that would increase speed? I had always assumed it would slow down the tip, because the kinetic energy is now being stored as potential in the flex of the blade.
  9. Aug 27, 2010 #8


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    That might be the fastest assuming it is allowed to flex back to a straight blade. You store up potential energy in the blade by bending it, and then when it whips out the potential energy is all converted to kinetic energy again
  10. Aug 28, 2010 #9
    Would it spring back faster than it had been traveling previously?
  11. Aug 28, 2010 #10


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    Most likely, yes.
  12. Aug 28, 2010 #11


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    Take a rubber band. Slowly stretch it out. Then let go. It certainly snaps back faster than when you pulled it.
  13. Aug 29, 2010 #12


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    That should be easy enough to test. We all know that a whip's tip exceeds the sound barrier on a regular basis. It seems to me that a foil, due to its construction, would be the fencing weapon most likely to match that. Wouldn't it be relatively simple to mount a sound transducer either on the tip or close to the target area which could register a "sonic boom"?
    Mugaliens, I'm with you on your firearms stance. It's illegal to carry a handgun at all here in Canada, so of course I carried concealed. Condition 1 Llama IX .45 in a home-made inside-the-waistband holster just to the right of my spine. All of the local cops, and the judge in my trial when I finally had to be busted due to a civilian complaint, knew that I was armed. They also knew whose side I was on. If something busted loose, they knew that I'd be shooting with them, not at them.
    I'm certain they knew because in my capacity as a waiter/bartender I used to serve the judge and his court staff and the RCMP staff their lunches on court days. Back then, I wore a tight (I think that it's called a "sweater vest" in the States; like a knitted tank-top) over a Super Blackhawk .44 Magnum with a 7 1/2" barrel in an upside-down shoulder holster. It wasn't exactly subtle.
    In 35 years, though, it came out of the holster only once... and that was resolved with no shots fired. I have no use for the more vocal NRA freaks, but a trained person carrying for a legitimate reason has my respect.
  14. Aug 29, 2010 #13


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    I think this kind of brings into question how far down you're allowed to go. A tennis serve goes 120 mph say, but if there's forespin then the part of the ball spinning forward will be traveling even faster. Does that count? Because it's no different than measuring just the tip of a sword being swung
  15. Aug 29, 2010 #14


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    I believe that it does, as in sports speeds. The original question, however, asked specifically about fencing. In that context, the tennis reference is irrelevant.
  16. Aug 30, 2010 #15
    I can't see how it might increase tip velocity, as at the moment of contact all forces (save vibrational) are reducing the tip velocity, and the vibrational forces are minute in comparison.

    I did a little more reading, and there are three weapons currently in use with fencing, the sabre, epee, and foil. They might be capable of breaking the sound barrier, if pushed hard enough. The foil is the lightest, while the Epee was invented in the second half of the 19th century by some folks who thought the foil was both too light and not realistic. Meanwhile, the sabre is a cutting weapon, though still quite modern and stylistically used for fencing.

    Regardless, I can break the sound barrier with the tip of a dampened towel, much to my brother's chagrin when we were children!

    Sorry bro, but you snapped me first...

    And yes, as documented by strobe photography, it does indeed break the sound barrier, as can any whip.
  17. Aug 30, 2010 #16


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    The issue is not whose side they are on while shooting,
    it is that a civilian - whose skills and training are a complete unkown to any but himself (a loose cannon, as it were) - is shooting at all.

    And no, their assurances that I can trust their training, temperament and judgment are insufficient.

    But you've had this discussion many times before, I'm betting.
  18. Aug 30, 2010 #17


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    The original question was about fencing, and speeds compared to speeds in other sports. Unless you're of the 'tennis is not a sport' crowd (which is very small I think)

    It's not going to increase speed when it hits the hilt, the speed is going to be when the sword slides off the hilt and snaps back to being straight
  19. Aug 31, 2010 #18
    I know that Andy Roddick's record 155 mph serve does not account for spin. Not being a tennis player, I'd stick with their criteria for speed when comparing tennis players, but I would count the spin in an intersport discussion. Although I wouldn't count anything like vibration speed of the strings.

    However, I don't think that measuring spin on a tennis ball is an equivalent level of nitpicking to measuring just the tip of a fencing weapon. I'd say a more appropriate comparison to measuring the speed of the tip compared to (whatever else you would measure instead) would be measuring the speed of the tennis ball vs the speed of the racket.

    By the way, instantaneous velocities from badminton far surpass tennis. But due to the rapid slowing immediately after the hit, tennis and badminton players argue a lot about which sport is really faster, adding an instantaneous-or-average speed layer of difficulty to the discussion.
    I would say that is an atypical action, but it does happen. http://flickershutter.com/June 18, 2006 SCHMF/pages/136g.html
  20. Aug 31, 2010 #19


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    The statement that you quoted was poorly expressed. I was thinking along the same line that Eroomynohtna mentioned. Some of those sports nuts who know every possible statistic might consider the surface speed of the ball to be relevant, but I'm pretty sure that officially it has to be the speed of the ball as a whole. I should have put more effort into the post.
  21. Aug 31, 2010 #20


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    The issue here is actually the speed of a fencing weapon. Can we save the gun-rights discussion for the politics forum?
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