Why you cannot use the flex # to move between brand poles
Moderator: Barto
- 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:
Why you cannot use the flex # to move between brand poles
Why you cannot use the flex # to move between brand poles
I had in the past heard that Spirits ran lighter than Pacers. And I believed this for many years, until last month our engineers discovered something.
In a test where we looked at 3-4 four similar flex size poles it was discovered that the design of the Pacer contributed stiffness to the entire pole in its design, and that other types of poles do not have the stiffness in the top of the pole as a Pacer does due to the design of their spiral wrap.
(A spiral wrap pole defined as one where the wrap provides 50% stiffness to the pole and 50% hoop to the pole the full length of the pole in the first layer applied to the pole.)
Further analysis yielded that when a pole has a stiffer top in its design this stiffness contributed to the reading and the rating of the flex number. Making the pole read slightly stiffer than it really was, thus even though the two brand poles were the same one had a stiffer flex rating.
Thus a spiral wrapped pole will read stiffer and you would think you could use a stiffer pole even though it would be the exact same pole as the one reading a lighter flex of another brand.
Now while this is immaterial and the numbers are so minute to each other, this does not cause any alarm to any safety concerns or inconsistency. (We have a flex measure device that measures in .0001 MM)
So in reality the Spiral wrap pole will read slightly stiffer in the flex number than it really is due to the contribution of the stiffness of the top of the pole the part that really does not bend during a well executed vault.
This problem is more of a difference in the comparisons of carbon poles to natural glass poles as the grip area is stiffer due to the full length stiffness applied to the design of this type pole.
It is further proof that it will be very difficult to align different brand’s flex number up with another even if they are both using the same measuring system and method.
We have stated before that flex numbers are really not for public use to move from one brand to another, But rather to use within the same brand and the same length as a guide only to fine tune your vault.
Note: The Spirit pole has a spin wrap that contributes very little too the stiffness of the pole and mostly hoop to the pole in its beginning wrap. Stiffness is control by its subsequent wraps and it special sail design.
Each of the brands above uses different methods to manufacture their product. Each manufacturer uses these methods to provide certain advantages in both performance and the manufacturing process.
I had in the past heard that Spirits ran lighter than Pacers. And I believed this for many years, until last month our engineers discovered something.
In a test where we looked at 3-4 four similar flex size poles it was discovered that the design of the Pacer contributed stiffness to the entire pole in its design, and that other types of poles do not have the stiffness in the top of the pole as a Pacer does due to the design of their spiral wrap.
(A spiral wrap pole defined as one where the wrap provides 50% stiffness to the pole and 50% hoop to the pole the full length of the pole in the first layer applied to the pole.)
Further analysis yielded that when a pole has a stiffer top in its design this stiffness contributed to the reading and the rating of the flex number. Making the pole read slightly stiffer than it really was, thus even though the two brand poles were the same one had a stiffer flex rating.
Thus a spiral wrapped pole will read stiffer and you would think you could use a stiffer pole even though it would be the exact same pole as the one reading a lighter flex of another brand.
Now while this is immaterial and the numbers are so minute to each other, this does not cause any alarm to any safety concerns or inconsistency. (We have a flex measure device that measures in .0001 MM)
So in reality the Spiral wrap pole will read slightly stiffer in the flex number than it really is due to the contribution of the stiffness of the top of the pole the part that really does not bend during a well executed vault.
This problem is more of a difference in the comparisons of carbon poles to natural glass poles as the grip area is stiffer due to the full length stiffness applied to the design of this type pole.
It is further proof that it will be very difficult to align different brand’s flex number up with another even if they are both using the same measuring system and method.
We have stated before that flex numbers are really not for public use to move from one brand to another, But rather to use within the same brand and the same length as a guide only to fine tune your vault.
Note: The Spirit pole has a spin wrap that contributes very little too the stiffness of the pole and mostly hoop to the pole in its beginning wrap. Stiffness is control by its subsequent wraps and it special sail design.
Each of the brands above uses different methods to manufacture their product. Each manufacturer uses these methods to provide certain advantages in both performance and the manufacturing process.
Last edited by Bruce Caldwell on Thu Nov 13, 2003 11:33 am, edited 3 times in total.
I love the PV, it is in my DNA
Sorry Mr. Caldwell but I could not disagree more.
Flex numbers only vary in how they are arrived at. If different methods are employed in determining flex numbers, then the numbers will be different and of relatively little use to vaulters and coaches; however....
If poles are flexed on the same spans then the amount of resistance the pole gives to the weight is a very good measure of the stiffness of the pole.
I have flexed all of my own poles and the poles of the athletes I have coached for many years. The stiffness of the pole is always determined by the flex number the pole measures out at. I have never seen a pole that measured as softer, but was actually stiffer than another pole flexed in the same manner. It does not matter what the sail position is, only the length of the pole.
Furthermore, I have flexed many carbon and fiberglass poles and have never seen a difference in the stiffness of poles with the same flex number. The poles may react very differently to each other, but the relative stiffness of the poles is always the same.
I only feel obligated to respond to this post because this post was presented as an absolute statement of fact when, in fact it was just one guy's opinion.
Barto.
Flex numbers only vary in how they are arrived at. If different methods are employed in determining flex numbers, then the numbers will be different and of relatively little use to vaulters and coaches; however....
If poles are flexed on the same spans then the amount of resistance the pole gives to the weight is a very good measure of the stiffness of the pole.
I have flexed all of my own poles and the poles of the athletes I have coached for many years. The stiffness of the pole is always determined by the flex number the pole measures out at. I have never seen a pole that measured as softer, but was actually stiffer than another pole flexed in the same manner. It does not matter what the sail position is, only the length of the pole.
Furthermore, I have flexed many carbon and fiberglass poles and have never seen a difference in the stiffness of poles with the same flex number. The poles may react very differently to each other, but the relative stiffness of the poles is always the same.
I only feel obligated to respond to this post because this post was presented as an absolute statement of fact when, in fact it was just one guy's opinion.
Barto.
- 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:
based on our test this is our opinion
Based on our test this is our opinion
[color=blue][b]Thanks for your input we need more of this.
And I am sorry, that I do feel so definitive on this subject, but you are right I need to state that based on our test this is our opinion.
And I felt the same way you do about this until we looked at 16’5â€Â
[color=blue][b]Thanks for your input we need more of this.
And I am sorry, that I do feel so definitive on this subject, but you are right I need to state that based on our test this is our opinion.
And I felt the same way you do about this until we looked at 16’5â€Â
I love the PV, it is in my DNA
Bruce,
your comments about flex numbers seem to be very helpful and I appreciate them. they have brought several insights about successful methods of deriving a universal flex system. i have several questions relating to your post. #1) any conclusions about my flex idea? i covet your extensive knowledge about poles, production thereof, etc. and therefore am interested in your opinions on whether or not you think it (my idea) has any merit. i think one part of it that needs adjusting is finding the right span to flex incorporating regions of the pole that are meant to flex, regions w/ sail piece, wrapping, etc. perhaps this would not allow for my idea of taking numbers and making them proprtionate (using a certain percentage of weight to flex as well as taking flex number w/ respect to length, max weight value, etc.)
also, how did you create your own version of the carbon fx? was it a very accurate representation of pacer's carbon fx, and what difference is there between it and your carbon axial? (or are those industry secrets, haha)
one last question. i feel rather ignorant not knowing the answer to this question, as it seems to be an elementary aspect of pole production/terminology, but I haven't been able to find the answer. what is hoop and/or the difference between hoop stiffness vs. wrapping stiffness? i look forward to reading your reply
your comments about flex numbers seem to be very helpful and I appreciate them. they have brought several insights about successful methods of deriving a universal flex system. i have several questions relating to your post. #1) any conclusions about my flex idea? i covet your extensive knowledge about poles, production thereof, etc. and therefore am interested in your opinions on whether or not you think it (my idea) has any merit. i think one part of it that needs adjusting is finding the right span to flex incorporating regions of the pole that are meant to flex, regions w/ sail piece, wrapping, etc. perhaps this would not allow for my idea of taking numbers and making them proprtionate (using a certain percentage of weight to flex as well as taking flex number w/ respect to length, max weight value, etc.)
also, how did you create your own version of the carbon fx? was it a very accurate representation of pacer's carbon fx, and what difference is there between it and your carbon axial? (or are those industry secrets, haha)
one last question. i feel rather ignorant not knowing the answer to this question, as it seems to be an elementary aspect of pole production/terminology, but I haven't been able to find the answer. what is hoop and/or the difference between hoop stiffness vs. wrapping stiffness? i look forward to reading your reply
- 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:
reply
I will answer you in a private email about your idea.
The FX we made was similar as they use a machine to Spiral, and we did it by hand. The pole was destroyed and was not sold, as we respect their process and designs as their own.
The Axial pole is being used by many vaulters already and is proving to be a more efficient way for us to produce carbon poles.
Hoop is the means for which fibers hold the pole in a tube position and the strength to keep it circular.
The stronger the hoop the better the pole will stay elliptical without load failure.
Hoop strength is derived by several methods , the selection of the mandrel and how large the diameter is, the amount of glass wrapped at 90 degrees around the pole.
A spiral wrap contributes 50% hoop and 50% strength towards both the longitude of the pole an the hoop of the pole.
A spin wrap contributes very little longitude strength but greater hoop. 95%-5%
We use a special glass configuration that contributes 90% hoop and 10% longitudinal strength.
The FX we made was similar as they use a machine to Spiral, and we did it by hand. The pole was destroyed and was not sold, as we respect their process and designs as their own.
The Axial pole is being used by many vaulters already and is proving to be a more efficient way for us to produce carbon poles.
Hoop is the means for which fibers hold the pole in a tube position and the strength to keep it circular.
The stronger the hoop the better the pole will stay elliptical without load failure.
Hoop strength is derived by several methods , the selection of the mandrel and how large the diameter is, the amount of glass wrapped at 90 degrees around the pole.
A spiral wrap contributes 50% hoop and 50% strength towards both the longitude of the pole an the hoop of the pole.
A spin wrap contributes very little longitude strength but greater hoop. 95%-5%
We use a special glass configuration that contributes 90% hoop and 10% longitudinal strength.
Last edited by Bruce Caldwell on Thu Nov 13, 2003 5:00 pm, edited 2 times in total.
I love the PV, it is in my DNA
Re: reply
ESSX wrote:
The Axial pole is being used by many vaulters already and is proving to be a more efficient way to produce carbon poles.
Exactly how is the Axial pole proving to be a more efficient way to produce carbon poles?
I don't mean to nit pick, but many of your statements are presented without any supporting evidence as universal truths. This board is a wonderful opportunity to ask questions and exchange ideas. I would prefer it not be used as a spring board for one person's opinions.
Barto
- 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:
That is what a bulletin board is posters opinions.
That is what a bulletin board is posters opinions.
Forum is defined as: Public discussion of a topic and the posters views and view points.
This post was to share something we discovered. Most all of my post on here are informative and provide non bias information to help vaulters. You are near us in Fort Worth TX.
I personally invite you to come and see our operations then you will understand more of why we have the passion to help vaulters.
Many posters on here have felt the same way you have until they have met and visited us.
I believe we offer more to the public than launching an opinion.
I am truly sorry that you seem to be disturbed by our opinions and postings!
I love the PV, it is in my DNA
- 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:
Post revised 11/23/03
The post on this forum posted by Bruce Caldwell, ESSXsport Corp, and under the alias of XLOGIC are our engineer's, Bruce Caldwell's, and the Company's, opinions based on the test and research we have done.
We stand behind our findings and have enjoyed sharing them with the Vaulting community.
Added 11/23/03
The Pole makers from Reno made a very good comment this past week that best describes why one cannot just set up a standard with the current method for Flexing all brand poles and why the flex number does not give you a means for moving from one brand to another.
In a comment they mentioned a part they make that when flexed with the proper spans reads the flex number equal to an 11-140. However they would never sell this part as a vaulting pole even though it was the same flex.
The reason was astounding and very true as this part they were talking about was their crossbar and it did not have the hoop or the proper design to be a vaulting pole and in no way would support the weight of a 140lbs vauter.
THIS WAS A GREAT EXAMPLE
[color=green][b]Added 11/23/03
Reference to lowering you’re handgrip on the pole to get a stiffer pole.
Another comment and better explanation made by another party this week was, When you lower the grip below the recommended grip area the pole may feel the resistance that of a stiffer pole.
This might provide one who does not understand vaulting pole designs to feel that they might be able to lower their grip on a 14-120 by 15â€Â
We stand behind our findings and have enjoyed sharing them with the Vaulting community.
Added 11/23/03
The Pole makers from Reno made a very good comment this past week that best describes why one cannot just set up a standard with the current method for Flexing all brand poles and why the flex number does not give you a means for moving from one brand to another.
In a comment they mentioned a part they make that when flexed with the proper spans reads the flex number equal to an 11-140. However they would never sell this part as a vaulting pole even though it was the same flex.
The reason was astounding and very true as this part they were talking about was their crossbar and it did not have the hoop or the proper design to be a vaulting pole and in no way would support the weight of a 140lbs vauter.
THIS WAS A GREAT EXAMPLE
[color=green][b]Added 11/23/03
Reference to lowering you’re handgrip on the pole to get a stiffer pole.
Another comment and better explanation made by another party this week was, When you lower the grip below the recommended grip area the pole may feel the resistance that of a stiffer pole.
This might provide one who does not understand vaulting pole designs to feel that they might be able to lower their grip on a 14-120 by 15â€Â
Last edited by Bruce Caldwell on Mon Nov 24, 2003 12:26 am, edited 3 times in total.
I love the PV, it is in my DNA
- rainbowgirl28
- I'm in Charge
- Posts: 30435
- Joined: Sat Aug 31, 2002 1:59 pm
- Expertise: Former College Vaulter, I coach and officiate as life allows
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- Gender: Female
- World Record Holder?: Renaud Lavillenie
- Favorite Vaulter: Casey Carrigan
- Location: A Temperate Island
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I'm sorry to hear Bruce is no longer posting here, at least for the time being, as he (and any others who posted under ESSX) have probably provided to me the most information on poles, sizing, flex numbers, manufacturing, etc. and I will miss his input. It's a shame that there are such jerks that get so offended over information that they have to go slandering and putting down others, and I hope it is put to an end. No one has the right to be an as$h*le jst because they think they're right.
I do nost post that often lately, but this has brought me to think about what vaulting is about and why I personally love it so much. As it has been described to me once, pole vaulting is like a giant fraternity, we are a brotherhood, that though has disagreements, we will move past it. We all are involved for the same reason, because we love to do it, and we have always been willing to share information to make each of us better. This is the same reason that the vault summit works and things like the sprint summit may not be as succesfull: vaulters are willing to help each other, even the guy next to them who might beat them. This is what seperates us from everybody else. I am really dissapointed to see that ESSX will no longer be posting for awhile becaues he was attacked. Yes, those are his opinions, but look at any other topic or post on this site as it is almost all opinion. Be willing to share and discuss ideas, lets not start attacking each other, to me, thats just not what vaulters do.
Champions aren't made in gyms. Champions are made from something they have deep inside them-a desire, a dream, a vision. They have to have last-minute stamina, they have to be a little faster, they have to have the skill and the will. But the will must be stronger than the skill. - Muhammad Ali
Talent in cheaper than table salt. What separates the talented individual from the successful one is a lot of hard work.
-Stephen King
Talent in cheaper than table salt. What separates the talented individual from the successful one is a lot of hard work.
-Stephen King
- 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:
We stand behind our findings and have enjoyed sharing them with the Vaulting community.
Added 11/23/03
The Pole makers from Reno made a very good comment this past week that best describes why one cannot just set up a standard with the current method for Flexing all brand poles and why the flex number does not give you a means for moving from one brand to another.
In a comment they mentioned a part they make that when flexed with the proper spans reads the flex number equal to an 11-140. However they would never sell this part as a vaulting pole even though it was the same flex.
The reason was astounding and very true as this part they were talking about was their crossbar and it did not have the hoop or the proper design to be a vaulting pole and in no way would support the weight of a 140lbs vauter.
THIS WAS A GREAT EXAMPLE
[color=green][b]Added 11/23/03
Reference to lowering you’re handgrip on the pole to get a stiffer pole.
Another comment and better explanation made by another party this week was, When you lower the grip below the recommended grip area the pole may feel the resistance that of a stiffer pole.
This might provide one who does not understand vaulting pole designs to feel that they might be able to lower their grip on a 14-120 by 15â€Â
I love the PV, it is in my DNA
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