Quit Cutting Poles

A forum to discuss everything to do with pole vaulting equipment: poles, pits, spikes, etc.

Moderator: Barto

User avatar
mcminkz05
PV Great
Posts: 894
Joined: Sat Feb 22, 2003 12:08 am
Expertise: College Vaulter
Location: Ann Arbor, Michigan
Contact:

Unread postby mcminkz05 » Sat Jul 12, 2003 1:00 am

I have an unusual length 12-9 UCS Spirit. does that ,mean that it was cut down ?? i didnt ever really look to see if it was cut, but i dont see that pole length anywhere....
What have you done today to get better?

User avatar
StickJumper
PV Nerd
Posts: 78
Joined: Fri Nov 22, 2002 12:20 pm
Location: Suwanee, GA
Contact:

A Reprieve

Unread postby StickJumper » Sat Jul 12, 2003 7:11 pm

Yes, it is okay to cut poles, if you know what you're doing. You're also usually able to buy poles by flex in the desired length to compensate for your desire to cut.

It was obvious to noticed that the bottom was the cut end. Take out a pole and look at the bottom end around the plug and about 6in up from there. The fiberglass is thicker in this area to compensate for all forces in this area (heavier and longer poles are easier to see this). By cutting this end off, a thinner fiberglass wall is required to resist the same forces. This also move forces throughout the pole to areas that have not been stressed in the same manner. Damaged hoops now make the pole more likely to be broken than before (we've all had a pole that got knocked around and was fine, now what's the condition).

And yes, I was inferring that should a pole break, they are designed to break in three. If everything goes right (good technique) during a vault, this aids in throwing the vaulter into the pit for safety functions.
"Not knowing where you are going is the best way to get somewhere you've never been."
Ryan Fussell- Pole Peddlers Admin.
http://www.polepeddlers.com

dubjones
PV Nerd
Posts: 76
Joined: Sun Sep 08, 2002 12:03 pm
Contact:

Unread postby dubjones » Sat Jul 12, 2003 9:31 pm

No, you cannot put poles back together. Well....you can....but you can't really jump on them anymore. It would be better to jump on the pieces. Maybe you blow through the smaller piece, and the next pole is right there. Poles buy three (maybe more) for the price of one.

Reality.
A pole breaking in more or less pieces won't "throw" a vaulter into the pit. It will make a loud sound, but not much "throwing" action. I hate to be rude about this, really do, but let us be serious about this for a minute. Talk to Brian, or Bruce, and I am sure that they will tell you that no pole brand is designed to break "safely". Sure, I would be willing to bet that some "safety" has been designed into each pole. Maybe to keep sharp fiberglass pieces from forming, I don't really know that. But, when a pole breaks, YOU ARE SCREWED, regardless of how many pieces. I am willing to say that every pole I have seen broken, (what I have seen only) has resulted in the vaulter landing in the pit. 2,3,4 pieces, same result. I can think of one close call, because the vaulter was out, big dip in the jump, so when the pole broke he was moving down rather than towards the back of the pit. In the event of a broken pole nothing is there to support the vaulter, nothing, so they fall, where they fall is a result of momentum at the point of breakage, not how many pieces the pole broke into.
When you cut a pole it will put stress in other areas of the pole that previously have not recieved that stress, I will agree. But, in my opinion, poles don't break because of this. If areas of a pole were not designed to take this type of stress, they wouldn't be part of a vaulting pole.

Stronger glass at the bottom of a pole.
Sure, in most cases you are right, there is more glass in this area. But....I would ask anyone on the board to tell us if you have ever broken a pole in the bottom 6"? Not 8", where it may hit the box, but rather the bottom 6".
Cutting poles.
Just to be honest here, I do have some poles that have been cut. I HAVE NEVER BROKEN ANY OF THEM. As a warning to nearly everyone, I DO NOT THINK YOU SHOULD CUT YOUR POLES. Poles are a big investment and there is a greater chance you will ruin a pole, rather than make it better.
People have jumped high on poles that have not, and have been, cut. STILL NOT the answer you are looking for if you want to jump high. (see indian/arrow). If a pole breaks, who cares if it was cut or not, unless it was cut.....in the middle. Poles don't break because they are cut off, they break for other reasons. I'll leave those up to you to figure out.
If you want to know why people cut poles do some research, it won't take long. Look at how poles are made, and think of how that changes when they are cut. Not that hard to do. I still do not, repeat, do not, want anyone on this board to cut poles. If someone else can jump high on what comes from the factory... SO CAN YOU. If it ain't broke, don't fix it. If it is broke, throw it away.
Sorry this went so long. I know most of you don't know me from Adam, and I may not know you, but this board is for discussion purposes. Those who do know me know my resume', so take from this what you will.
There is still more info out there, but I won't argue about this topic. I don't beleive it is a safety issue, cut or not. If you take some time with this topic I am sure you will find the same.
Dub
KRAP,3MG.

User avatar
StickJumper
PV Nerd
Posts: 78
Joined: Fri Nov 22, 2002 12:20 pm
Location: Suwanee, GA
Contact:

Wholeheartedly agree

Unread postby StickJumper » Sat Jul 12, 2003 11:18 pm

1. It is true that people can cut poles and still be fine. What I'm hoping to point out is that if you don't what you're doing, you can change the parameters (wieght/flex) of a pole to something that you can not handle. It's like putting a manual transmission in your car and playing with the gear ratios and aspects (which I doubt anyone here does). If you can't drive a stick (no pun intended), what good does some extra horsepower do you. Long Run: if you don't know how to do it properly, don't do it. The kid at the meet had told us earlier that he himself had cut it.

2. If for any reason whatsoever you are compelled to cut a pole, inspect it first. As Bruce pointed out, if there was a blimish/spike mark/split/anything in an area that would not generally be detremental, you may be okay. However, the problem lies in that a redistribution of force to less stressed areas could cause gradual wear on these areas, expanding them to the point when the fiberglass has had enough.

3. From what I understand, and someone please do correct me if I am wrong for I don't want to preach an untruth, that when poles are manufactured, there is a "safety system" that is in the design so that when a pole breaks (justifying if it ever would for any reson), the pole will snap in two locations just above and below the sailpiece so that there is not more substantial deviation of break. Someone who knows please agree to or refute this as this is how I have come to understand it.

4. The whole "throwing into the pit" deal. It is justified in that force vectors can be changed as to the position of the break causing an undesired response, allowing the momentum of the runway to be changed in direction itself. In other words, there is a force vector from the athlete towards the pit from the athlete's run. A second vector is the jump of the athlete in the up and out motion. The third vector is a culmination of the vaulter's swing and the unbending action of the pole. Obviously this vector is mostly up, but has parts of an outward motion. The next part is considering no outside factors such as wear and tear, fraying, chipping, spikes, etc.
- A vaulter proceeds to vault (uncut pole), and for some reason, the pole breaks. According to how a pole will break in #3 (assuming this is correct), the vertical vector is eliminated and you are left with three vectors equalling a motion towards the pit. The break is in the middle of the pole and the vaulter is pushed through the middle by said vectors.
- Now, a vaulter proceeds to vault (cut pole), and for some reason, the pole breaks. According to how a pole will break in #3 (assuming this is correct), the vaulter is again sent through the middle of the pole and lands on the pit. However, because the pole is cut, this "safety system" is positioned lower or higher on the pole (assuming the two poles are now the same length), so the vectors towards the pit are lower or higher, too. This creates the undesired motion towards the pit as far as where in the pit, or maybe the box, you will land.

This has all been too long, and I may very well be wrong in areas. The whole idea though is that experienced vaulters are in a position where occurances are better handled to to being in correct positions. However An inexperienced vaulter on a pole that they can not be certain how to handle can have lasting effects.
"Not knowing where you are going is the best way to get somewhere you've never been."

Ryan Fussell- Pole Peddlers Admin.

http://www.polepeddlers.com

User avatar
lonestar
PV Lover
Posts: 1475
Joined: Sat Oct 12, 2002 12:23 am
Location: New Braunfels, TX
Contact:

Re: Wholeheartedly agree

Unread postby lonestar » Sun Jul 13, 2003 1:28 am

StickJumper wrote:1. It is true that people can cut poles and still be fine. What I'm hoping to point out is that if you don't what you're doing, you can change the parameters (wieght/flex) of a pole to something that you can not handle. It's like putting a manual transmission in your car and playing with the gear ratios and aspects (which I doubt anyone here does). If you can't drive a stick (no pun intended), what good does some extra horsepower do you. Long Run: if you don't know how to do it properly, don't do it. The kid at the meet had told us earlier that he himself had cut it.

2. If for any reason whatsoever you are compelled to cut a pole, inspect it first. As Bruce pointed out, if there was a blimish/spike mark/split/anything in an area that would not generally be detremental, you may be okay. However, the problem lies in that a redistribution of force to less stressed areas could cause gradual wear on these areas, expanding them to the point when the fiberglass has had enough.

3. From what I understand, and someone please do correct me if I am wrong for I don't want to preach an untruth, that when poles are manufactured, there is a "safety system" that is in the design so that when a pole breaks (justifying if it ever would for any reson), the pole will snap in two locations just above and below the sailpiece so that there is not more substantial deviation of break. Someone who knows please agree to or refute this as this is how I have come to understand it.

4. The whole "throwing into the pit" deal. It is justified in that force vectors can be changed as to the position of the break causing an undesired response, allowing the momentum of the runway to be changed in direction itself. In other words, there is a force vector from the athlete towards the pit from the athlete's run. A second vector is the jump of the athlete in the up and out motion. The third vector is a culmination of the vaulter's swing and the unbending action of the pole. Obviously this vector is mostly up, but has parts of an outward motion. The next part is considering no outside factors such as wear and tear, fraying, chipping, spikes, etc.
- A vaulter proceeds to vault (uncut pole), and for some reason, the pole breaks. According to how a pole will break in #3 (assuming this is correct), the vertical vector is eliminated and you are left with three vectors equalling a motion towards the pit. The break is in the middle of the pole and the vaulter is pushed through the middle by said vectors.
- Now, a vaulter proceeds to vault (cut pole), and for some reason, the pole breaks. According to how a pole will break in #3 (assuming this is correct), the vaulter is again sent through the middle of the pole and lands on the pit. However, because the pole is cut, this "safety system" is positioned lower or higher on the pole (assuming the two poles are now the same length), so the vectors towards the pit are lower or higher, too. This creates the undesired motion towards the pit as far as where in the pit, or maybe the box, you will land.

This has all been too long, and I may very well be wrong in areas. The whole idea though is that experienced vaulters are in a position where occurances are better handled to to being in correct positions. However An inexperienced vaulter on a pole that they can not be certain how to handle can have lasting effects.


Your first point: I agree with - if you don't know what you're doing, don't mess with it. Over 50% of my club poles are chopped, and only 2 of the 5 total we've broken in the past 3 years were chopped and broke from other damage unrelated to being chopped.

Your 3rd point: Poles are not designed to break at any point. Poles are designed with a sailpiece in a certain area to displace stress evenly throughout the pole. They tend to break at the bottom and top of the sail because the glass is thinner in those areas, and if they are overstressed in those areas usually because of a bad takeoff and levering or pulling, will break there - not because they're designed to break there for safety, but because the technical fault of the vaulter created an uneven distribution of stress throughout the pole.

Your 4th point: One simple term: Inertia: a body in motion tends to stay in motion in a straight line unless disturbed by and external force. Landing in the pit after breaking a pole is a result of the momentum from the run and inertia created, not how the pole broke. Like Dub, I've seen dozens of poles break, and the only cases of people not landing in the pit was when they were extremely out and/or sat on the pole creating a downward takeoff angle/trajectory at the time of the break, thus making them land in the box (indian/arrow again).

User avatar
Bruce Caldwell
PV Enthusiast
Posts: 1783
Joined: Thu Feb 27, 2003 3:19 pm
Expertise: It is all about Pole Vaulting. I even catch the competitors poles!
Lifetime Best: 15'8"
Favorite Vaulter: Kjell Issakson, Jan Johnson
Location: DFW TEXAS
Contact:

ESSX Wholeheartedly agreeS TOO WELL SAID

Unread postby Bruce Caldwell » Sun Jul 13, 2003 10:41 am

Your first point: I agree with - if you don't know what you're doing, don't mess with it. Over 50% of my club poles are chopped, and only 2 of the 5 total we've broken in the past 3 years were chopped and broke from other damage unrelated to being chopped.

Your 3rd point: Poles are not designed to break at any point. Poles are designed with a sailpiece in a certain area to displace stress evenly throughout the pole. They tend to break at the bottom and top of the sail because the glass is thinner in those areas, and if they are overstressed in those areas usually because of a bad takeoff and levering or pulling, will break there - not because they're designed to break there for safety, but because the technical fault of the vaulter created an uneven distribution of stress throughout the pole.

Your 4th point: One simple term: Inertia: a body in motion tends to stay in motion in a straight line unless disturbed by and external force. Landing in the pit after breaking a pole is a result of the momentum from the run and inertia created, not how the pole broke. Like Dub, I've seen dozens of poles break, and the only cases of people not landing in the pit was when they were extremely out and/or sat on the pole creating a downward takeoff angle/trajectory at the time of the break, thus making them land in the box (indian/arrow again).




ESSX Wholeheartedly agrees too
WELL SAID
Last edited by Bruce Caldwell on Wed Sep 24, 2003 10:44 pm, edited 1 time in total.

User avatar
vaultdad
PV Whiz
Posts: 154
Joined: Thu Jul 10, 2003 10:45 pm
Expertise: An Official
Favorite Vaulter: Jillian Schwartz!
Location: Eastern Missouri

Why poles break in multiple pieces

Unread postby vaultdad » Sun Jul 13, 2003 12:30 pm

I was trying to figure this out using the physics I learned in college, when I pulled a muscle in my head and passed out for a while . . .

But, allowing for the construction of the pole, and the energy stored in it at its maximum loading, doesn't it seem like the sine wave shockwave down the pole when going from a kinetic energy loaded state to an uncontrolled enery release state is what shatters the pole? I'd bet the first broken joint goes to near supersonic speeds in the time it takes us to hear it, and then see it.

I have seen poles broken from being spiked that made no sound at all, but sure surprised the crowd. I'd be curious how many poles have been ruined by an upset youth vaulter who throws their pole on the ground after a poor vault, not realizing the damage inflicted on the pole is greater than the damage to their pride.

Decamouse
PV Great
Posts: 923
Joined: Thu Oct 24, 2002 6:43 pm
Expertise: Masters vaulter, coach, USATF Official
World Record Holder?: Renaud Lavillenie
Favorite Vaulter: Kate Dennison
Location: Bohners Lake, Wisconsin
Contact:

Been a long weekend

Unread postby Decamouse » Sun Jul 13, 2003 2:09 pm

Lost of comments on this one - first to my knowledge we do not design or intend to design a pole to break or if it does - break in a certain place.

The single point break can many times be traced back to the damage, spiek, ding, whatever.

Vaultdad hit the multi break pretty good - if the pole is simply over powered - or over bent - the undamaged pole is going to have the stress level high in numerous sections - once it lets loose, the shock, force reversals, can cause multi break points - we have been testing some prototype poles and material - and have some fracture in as many as five places once they fail. Since a machine you can get a more even loading (not levering, squating etc.) you can load the pole to its max and beyond - and if the pole is designed to not have stress risers, and under normal loading will have stress fairly evenly distributed - you can/should see the multi point failure.

Lots of good info on this thread - :idea:
Plant like crap sometimes ok most times

User avatar
Aviendha
PV Pro
Posts: 336
Joined: Wed Mar 19, 2003 3:41 pm
Expertise: Current Collegiate Vaulter
Location: Missouri
Contact:

Re: Why poles break in multiple pieces

Unread postby Aviendha » Sun Jul 13, 2003 2:22 pm

vaultdad wrote:I'd be curious how many poles have been ruined by an upset youth vaulter who throws their pole on the ground after a poor vault, not realizing the damage inflicted on the pole is greater than the damage to their pride.


actually, one of my school's guy vaulters did just that...but the pole didn't break the next time it was vaulted on, it broke when he threw it against the concrete storm drain (he had grabbed a girls 12-130 and thrown it instead of his pole...)
~Why does everyone prefer those who lie and make themselves less than they are, rather than those who embrace who they are, rejoice in it, and refuse to pretend anything less?

Skyin' Brian
PV Master
Posts: 681
Joined: Mon Jul 14, 2003 12:42 pm
Location: illinois
Contact:

Unread postby Skyin' Brian » Mon Jul 21, 2003 4:47 pm

here is a story about cutting poles:
my college had a vaulter about ten years ago that vaulted on cut spirits. he thought he needed a bigger pole for the national meet so because of timing issues the school had the pole shiped to the national meet and it arrived during warm ups. the athlete pulled a hacksaw out of his bag and cut a section out of the bottom of then walked to the back of the runway and took it up.

User avatar
lonestar
PV Lover
Posts: 1475
Joined: Sat Oct 12, 2002 12:23 am
Location: New Braunfels, TX
Contact:

Unread postby lonestar » Mon Jul 21, 2003 6:32 pm

Skyin' Brian wrote:here is a story about cutting poles:
my college had a vaulter about ten years ago that vaulted on cut spirits. he thought he needed a bigger pole for the national meet so because of timing issues the school had the pole shiped to the national meet and it arrived during warm ups. the athlete pulled a hacksaw out of his bag and cut a section out of the bottom of then walked to the back of the runway and took it up.


Then what happened? :confused:

User avatar
Vaulterchick88
PV Pro
Posts: 282
Joined: Fri Jun 27, 2003 2:46 pm
Location: Seattle, WA
Contact:

Unread postby Vaulterchick88 » Mon Jul 21, 2003 8:45 pm

Skyin' Brian wrote:here is a story about cutting poles:
my college had a vaulter about ten years ago that vaulted on cut spirits. he thought he needed a bigger pole for the national meet so because of timing issues the school had the pole shiped to the national meet and it arrived during warm ups. the athlete pulled a hacksaw out of his bag and cut a section out of the bottom of then walked to the back of the runway and took it up.

omigosh that's nuts
"Life is not measured by the number of breath you take, but by the number of moments that take your breath away"
- Anonymous


Return to “Pole Vault - Equipment”

Who is online

Users browsing this forum: No registered users and 19 guests