Pole Charts

[drcurran]

I know I've seen such a thing, but looking around can't find what I remember seeing. This was a chart (can't remember which company maybe several) comparing pole length and weights (maybe flex # too) and hand grip. Anybody remember seeing such a thing. Thanks!

Dan

[rainbowgirl28]

http://www.skyjumpers.com/articles/pvpr ... table.html

[drcurran]

Thanks Becca just want I wanted / needed.

Dan

[golfdane]

We got a lot of unmarked poles. I've built a rig to test the flex numbers on each of them. I've seen somewhere (possible in a Gill paper), that a 5m pole is measured with a 4.3m span. What would be my best guess as to what to use as span on different pole lengths? Percentage of pole length, or a fixed amounts of cm's from bottom and top (like 30cm from bottom, 40cm from top (my roller will be placed at top end)), regardless of pole length?

Anyone have a chart that'll convert flex into approximate lbs for different pole lengths?

[rainbowgirl28]

We got a lot of unmarked poles. I've built a rig to test the flex numbers on each of them. I've seen somewhere (possible in a Gill paper), that a 5m pole is measured with a 4.3m span. What would be my best guess as to what to use as span on different pole lengths? Percentage of pole length, or a fixed amounts of cm's from bottom and top (like 30cm from bottom, 40cm from top (my roller will be placed at top end)), regardless of pole length?

Anyone have a chart that'll convert flex into approximate lbs for different pole lengths?

I think most manufacturers go 6" from the bottom of the pole and 1'6" from the top. So about 15cm and 45cm.

You're never going to be able to get your flex numbers to match up perfectly with the manufacturers flex chart. What you can do is measure your poles yourself to get a rough idea of the relative stiffness between them.

[golfdane]

Thx Becca

Yeah, I was thinking of using the exact same method for every pole (and not trying to find the manufacturers spec for a given pole). Just not sure whether to go for a fixed number or a percentage of the pole length. But 15/45 sounds reasonable (the stiff bottom away, and app. the middle of the "effective" grip area).

Still, it would be nice to have an approximate weight for each pole (not everyone here in Denmark is accustomed to flex numbers, and wouldn't know if a 425, 21.6 compares app. to a 425, 145).

I'm trying to get the boys here familiar with flex numbers, and trust them more than lbs.

[KirkB]

Golfdane, since you're going to measure the relative flex of each pole in comparison to other poles of the SAME length, it wouldn't hurt to do one additional measurement for each pole ...

For each step up to a longer pole (e.g. for comparing 14-0 poles to 14-6 poles), measure the distance from the BOTTOM of the pole to the TOP fulcrum point - just as a vaulter would measure his grip - to get the comparative flex number of poles of "close but unequal" lengths.

Then you can compare apples to apples.

e.g. you will know [relatively] how much heavier a certain 14-6 pole is than a certain 14-0 pole.

Kirk

[rainbowgirl28]

Thx Becca

Yeah, I was thinking of using the exact same method for every pole (and not trying to find the manufacturers spec for a given pole). Just not sure whether to go for a fixed number or a percentage of the pole length. But 15/45 sounds reasonable (the stiff bottom away, and app. the middle of the "effective" grip area).

Still, it would be nice to have an approximate weight for each pole (not everyone here in Denmark is accustomed to flex numbers, and wouldn't know if a 425, 21.6 compares app. to a 425, 145).

I'm trying to get the boys here familiar with flex numbers, and trust them more than lbs.

Right, but each manufacturer has their own translation from flex numbers to pounds, and none of them are going to share that information.

What you can do is measure your poles with weight ratings as well as your poles without. Measure other people's poles too. The more you measure, the better idea you will have.

[KirkB]

... Right, but each manufacturer has their own translation from flex numbers to pounds, and none of them are going to share that information. ...

And yet the NFHS have a rule that a vaulter's weight cannot exceed the "official" weight of the pole.

If the "weight" varies from mfr to mfr for the same flex of pole, then there's a potential flaw, as one school using one mfr's poles might be PERCEIVED to have a competitive advantage (if it's really an advantage - but I don't really think it is - I think it's really just a safety issue) over another school using a different mfr's poles.

If it's only the "flex" that varies from mfr to mfr, then there's no real issue, other than an issue of confusion.

i.e. Even if the FLEX might vary from one mfr to another, the WEIGHT should not vary. It needs to be measured exactly the same way for ALL mfrs. No?

Worst case would be a HS coach or vaulter purposely buying a certain brand of poles because they know (or think) that they're calibrated "lighter" than other brands.

Now back to my previous post, if the NFHS goes only by weight, then maybe flex shouldn't matter at all, EXCEPT when:

(a) you're comparing the flex of two poles of unequal length AND same grip, or

(b) comparing the flex of two poles of equal length AND equal weight AND same grip?

Golfdane, I realize you're in Denmark - not bound by the rules and auspices of NFHS. My point only refers to USA HS vaulters. Is there any similar governing body in Denmark - or elsewhere in Europe - with similar weight restrictions?

One other point, and pardon my ignorance about modern day poles, but in my day, the weight of the pole was nominal, but the flex of the pole was exact. If you wanted to be "more exact", you went by flex; otherwise you went by weight. So what's different today?

The reason for this question is that I would think that if mfrs want to sell more poles - and they know that the weight marked on the pole is a "selling feature" - then would they not want to be more exact about the PRECISE weight of the pole - rather than just a nominal weight which is to the nearest 5 pounds? i.e. To truly be exact, then maybe the weight marked should be to the nearest pound?

Kirk

[vaultwest]

Kirk
basically the flex chart is how poles are separated into smaller weight increments. Right now Gill has about 350 different models of poles in their catalog so if they used their flex chart to make the models go up by 1 pound increments instead of 5 then they would have to list 1400 models and then of course they would have to stock that many different poles and all of us dealers would have to also stock so many poles that this system would be unmanageable. In a perfect world you would have that opportunity but for now knowing how the flex rating works allows for basically the same thing. One other thing for nearly 95% of all vaulters especially high school vaulters the five pound jump is a sufficiently small increment as vaulters go from one pole to the next bigger pole.
Vault On

[Pogo Stick]

Thx Becca

Yeah, I was thinking of using the exact same method for every pole (and not trying to find the manufacturers spec for a given pole). Just not sure whether to go for a fixed number or a percentage of the pole length. But 15/45 sounds reasonable (the stiff bottom away, and app. the middle of the "effective" grip area).

Still, it would be nice to have an approximate weight for each pole (not everyone here in Denmark is accustomed to flex numbers, and wouldn't know if a 425, 21.6 compares app. to a 425, 145).

I'm trying to get the boys here familiar with flex numbers, and trust them more than lbs.

This is from excellent article at Essx website (http://officialessx.com/forum/index.php?act=Print&client=printer&f=171&t=16):
"The flex number of a 12' 2" PVC plastic tube is the same as 12'-125 lbs test pole but you could not vault with it could you?"
"A flex number is a very general, non-scientific way of comparing the stiffness of a pole to all the other poles without regard pattern and glass properties."

From my understanding the flex number does not tell you much about weight rate. It is ok for comparing same length poles, otherwise you can end up with same flex number for different combinations of pole weights and lengths.

[KirkB]

basically the flex chart is how poles are separated into smaller weight increments. Right now Gill has about 350 different models of poles in their catalog so if they used their flex chart to make the models go up by 1 pound increments instead of 5 then they would have to list 1400 models and then of course they would have to stock that many different poles and all of us dealers would have to also stock so many poles that this system would be unmanageable. ...

Thanks Vaultwest, it makes sense, and I thought that might be the reasoning. That's just how it's always been.

But ... and I'm not trying to change the world here ... I'm just trying to clarify "fact" from "false logic" ...

Poles are assigned a model # by: (a) the brand; (b) the length; and (c) the weight. This is a voluntary choice that each mfr makes.

The premise of the mfrs and their dealers is that:

1. the RULE is tied to the WEIGHT,
2. the WEIGHT and LENGTH are tied to the MODEL,
3. the MODEL is tied to the SKU (unique Stock Keeping Unit identifier),
4. each dealer would like to (I assume), stock as many SKUs in inventory as is "practical" (based on cost-efficient inventory practices, and based on the demographics and buying habits of his customers)

Notice that the RULE is not tied to the MODEL, nor the LENGTH, nor the FLEX, nor the SKU, nor the [desired] inventory of the mfr or of each dealer.

So if increments of 5 pounds suffice at the HS level, then ALL poles of a certain weight that a dealer stocks could be the exact same length and flex. OK, maybe not the same length, as different vaulters have different grips, so they need different lengths. But a smart coach (?) should buy only the LOWEST flex #s of each 5 pound increment - to comply with the NFHS rules, yet allow his "beginner" vaulters to use the lightest poles allowed under the rules.

I'm not saying that the SKUs or the MODELS should be changed. I'm just saying that REGARDLESS of MODEL or SKU (brand, weight, length), the smart mfr and the smart dealer still need to be cognizant of the NFHS rules, and still need to stock the appropriate number of poles at the appropriate FLEX. Regardless of MODEL or SKU. So the argument that "... all us dealers would have to stock so many poles that this system would be unmanageable" is weak.

Maybe what you didn't notice is that - like it or not - you're stocking at the FLEX level!

And I suspect (but don't know for sure) that the mfr doesn't have complete control over the exact flex. I suspect that there's some variability in the mfg process, the flex # is measured AFTER the poles are built, and this might be what causes a range of flexes for each weight/length.

I'm interested in the details - and I certainly don't know them all - but I will guess that on the one side, the dealer might request certain flexes "to cover a range within a weight and length" (or maybe asks for the LIGHTEST flexes of a MODEL), and on the other side, the mfr will send the dealer what he has in stock. i.e. instead of specific back orders for specific flexes, there's some give-and-take on what's requested and what's received/accepted. After all, the order is for a SKU, and the specific FLEX would only be added "nice-to-have" comments (verbal or written) when the order is placed - not firm specs.

Now, if the dealer really wanted EXACT flexes, then wouldn't it be better to order an EXACT SKU that specifies that? i.e. to prevent substitutions.

I know I'm getting into a lot of detail re FLEX and WEIGHT. Really, my main points are that:

1. the mfr and dealer still have freedom of choice (within reason) to stock whatever exact flexes they want of each model; and
2. the NFHS rules aren't perfect - there's still the potential of SLIGHT competitive advantages for lighter poles
3. there's still "confusion in the marketplace" due to the inconsistencies of flexes between mfrs

BTW, I think the Gill CarbonFX Weave and PacerFX poles have a consistent FLEX throughout all their pole weights and lengths. I believe they're the first mfr to do this. So maybe Gill (Pacer and Pacer Carbon brands) and the other mfrs will follow suit, and then this issue is then resolved?

Kirk