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Fie halts visors... From the front page: According the the Swedish site and the FIE, the accident occurred in the round of 64 and the foil blade did not break in the action. The accident resulted in a cut to Latvian fencer Davids Gasilovskis. Gasilovskis was able to continue the bout after an injury time out.
I'm sorry, but there's NO WAY a foil blade is going to pierce lexan, breaking the lexan when the foible has as much play as it does... especially sprung lexan.
My guess is that this Latvian fencer may have been using substandard plastic.
If the foil broke, a la Smirnov, I'd find it infinitely more plausible. Jagged tip meets plastic... sure. I buy that.
But a fully mounted foil with tip? Hell no. Somethings wrong here. -
Posting Hound
Array  Originally Posted by fatfencer
I'm sorry, but there's NO WAY a foil blade is going to pierce lexan, breaking the lexan when the foible has as much play as it does... especially sprung lexan. Could be a combo of poor care of the mask and the blade hitting at just the right angle to put all of the force into the lexan....the blade may not actually bend right away (as I've found when taking sternum hits....ouch!) -
Admittedly its possible... either way Davids Gsdhanciwelliokis or whatever his name was is one lucky guy. -
Senior Member
Array  Originally Posted by fatfencer From the front page: According the the Swedish site and the FIE, the accident occurred in the round of 64 and the foil blade did not break in the action. The accident resulted in a cut to Latvian fencer Davids Gasilovskis. Gasilovskis was able to continue the bout after an injury time out.
I'm sorry, but there's NO WAY a foil blade is going to pierce lexan, breaking the lexan when the foible has as much play as it does... especially sprung lexan.
My guess is that this Latvian fencer may have been using substandard plastic.
If the foil broke, a la Smirnov, I'd find it infinitely more plausible. Jagged tip meets plastic... sure. I buy that.
But a fully mounted foil with tip? Hell no. Somethings wrong here.
Just guessing based on the 2 or 3 times I have been hit but, I think the potential energy of a foil tip probably increases with blade flexibility. As a function of velocity, a la flick. It does not surprise me that this sort of thing would happen with a foil. At any rate, I guess we'll have to wait for the report or possibly we will never know. I'm a foil fencer, and I can change, if I have to, I guess. -
Posting Hound
Array  Originally Posted by Joe biebel Just guessing based on the 2 or 3 times I have been hit but, I think the potential energy of a foil tip probably increases with blade flexibility. As a function of velocity, a la flick. It does not surprise me that this sort of thing would happen with a foil. At any rate, I guess we'll have to wait for the report or possibly we will never know. Wouldn't the bending blade absorb some of the energy of the hit, tho? -
Senior Member
Array This is more than a possibility as its been demonstrated with seemingy weak and flexible items as "straw in the tornado penetrates telephone pole" A foil moving at high speed concentrating all its energy at one small point and remaining unflexed for just a few milliseconds could become, at that instant, a rigid small diameter projectile. Unless the lexan is found to be faulty, which is unlikely unless the fencer replaced the visor with some unapproved generic item. If the blade breaks, usually at flex, the springing forward of the blade, combined with forward speed of both fencers has penetrated quality metal mesh and could easily pierce lexan. All this IMO and some observation. -
Senior Member
Array People have had ribs broken by a Foil hit. Whoopee! My avatar is back. -
Senior Member
Array -
Yeah, after a few years crop dusting and watching things like grasshoppers come through lexan canopies thicker than masks, this just reconfirms that the last day I fence is the first day visor masks are required for Epee. Although some would argue that the last day I fence was a few years ago.
Based on aircraft experience, I would guess that the failure was caused by cold flexing during install leaving stress risers at the curve. Solution would be hot installs, but not many folks are equipped or willing. -
Posting Hound
Array  Originally Posted by BAD KNEE 2 Based on aircraft experience, I would guess that the failure was caused by cold flexing during install leaving stress risers at the curve. Solution would be hot installs, but not many folks are equipped or willing. Probably not...installation is by unscrewing the frame around the plate....it's simple pressure that holds it in...no heat involved. -
Senior Member
Array A lot of private aircraft, especially old Cubs, etc. use Plexiglas, not Lexan. I'm not sure if this is still true. You are right about it being much thicker and if a grasshopper (not the Grasshopper) can punch through........ My real point is about the physics of impact - maybe that is the part that needs investigating by visor mask manufacturers. If ribs(flexible) can be broken so can Lexan. Even the rubber gasket solution faces the same problem if the point of the weapon hits at the correct angle and maintains its rigidity long enough. A broken blade can pierce a mesh mask and would likely go through a Lexan visor easier than an intact foil point. -
Senior Member
Array Now I understand that Plexiglas & Lexan are different, but a foil is made of metal... birds aren't, and they still do stuff like this at 100 mph... http://www.youtube.com/watch?v=o4L8OvB6kC4 In Flanders fields the poppies grow - Between the crosses, row on row, - That mark our place, and in the sky, - The larks, still bravely singing, fly, - Scarce heard amid the guns below. ~John McCrae -
Posting Hound
Array  Originally Posted by Wetmelon Birds have a lot more mass to bring to the table.....you really can't compare between a bird strike and a foil tip. -
yeah you are right about aircraft using plexiglas i know a lot of the kit planes such as cubs still use it today. It is because of the velocity the tip has when hitting the mask mixed with its mass. Although the tip doesn't have much mass the small area causes a large ammount of force to be applied to a very small point which can cause a failure in the material. The mask companys shuld definately look into a stronger polymer but more than likely it will increase the price. However, I would prefer the spend an extra $50 then have a foil stab me in the face 
Also, yes the bending of the foil will absorb energy and will lower the force applied to the visor. There is an instant where the foil is rigid and has yet to bend. If the force applied at this instant of the visor is higher than the ultimate strength of the material the mask will fail (break) regardless of how long the force is applied. Also, it could be due to being hit in the visor repeatedly even if the force is below the strength of the visor (fatigue failure).
Last edited by mach11; 11-08-2009 at 11:20 PM.
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Senior Member
Array  Originally Posted by touchefriend This is more than a possibility as its been demonstrated with seemingy weak and flexible items as "straw in the tornado penetrates telephone pole"... Hmm, while I understand your point here, I'm gonna have to say no on this one.
. . "I've been ionized, but I'm okay now." - Buckaroo Banzai . -
Armorer
Array  Originally Posted by mach11 yeah you are right about aircraft using plexiglas i know a lot of the kit planes such as cubs still use it today. It is because of the velocity the tip has when hitting the mask mixed with its mass. Although the tip doesn't have much mass the small area causes a large ammount of force to be applied to a very small point which can cause a failure in the material. The mask companys shuld definately look into a stronger polymer but more than likely it will increase the price. However, I would prefer the spend an extra $50 then have a foil stab me in the face
Also, yes the bending of the foil will absorb energy and will lower the force applied to the visor. There is an instant where the foil is rigid and has yet to bend. If the force applied at this instant of the visor is higher than the ultimate strength of the material the mask will fail (break) regardless of how long the force is applied. Also, it could be due to being hit in the visor repeatedly even if the force is below the strength of the visor (fatigue failure). I don't think the companies will look into a new polymer unless the FIE forces the issue. There is almost no specifications on the visor; while on the mesh there is a lot. They are looking at their bottom line, since most fencers also look at the cost. They will use whatever they can that will cost the least.
I have found nothing in the rulebook that would not allow fencers to get replacement visors from someone besides the manufacturer. On every other piece of equipment that requires homologation the manufacturer must have a mark. They are doing it on tips and barrels now. Donald Hollis Clinton, Jr. DHCJr@juno.com
To Teach is to Learn (Japanese Proverb)
Knowing the rule book by heart means nothing, if you don't understand the rules. -
Senior Member
Array No to what? That there is no possibility of penetration of a visor by a foil tip? No to straw being driven into wood? No to bird (soft and flexible) breaking the plexiglas canopy of a small plane. I for one doubt that the lexan was compromised before being struck by the intact foil tip. I could also be wrong. -
Moderator
Array This subject is already being discussed in this thread: Punctured mask at European Jr Championships
I know there's a lot to go through but you will find the points being discussed here are already being discussed there. Check out the Materials Science link in one of the posts - the bottom line being, yes there are alternatives.
We do not need a 2nd thread discussing this so I am closing this one down. Ple Similar Threads -
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