pole flex
Moderator: Barto
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- PV Beginner
- Posts: 23
- Joined: Sat Oct 21, 2006 11:50 pm
pole flex
Will the flex change as the pole gets older? more used? or change in temperature?
- Bruce Caldwell
- PV Enthusiast
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- Expertise: It is all about Pole Vaulting. I even catch the competitors poles!
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YES it can due to 2 things
A pole flex can only change when it loses material.
1. by cutting th epole at the butt
2. Poles in the past were made with a filament thread running the hoop wrap of the pole and this was applied with a resin on the mandrel. If the pole was flexed too far this resin crackled and was deposited at the butt of the pole. Look and see if your pole does this if so the flex can be a bigger number and the pole will be softer to bend.
1. by cutting th epole at the butt
2. Poles in the past were made with a filament thread running the hoop wrap of the pole and this was applied with a resin on the mandrel. If the pole was flexed too far this resin crackled and was deposited at the butt of the pole. Look and see if your pole does this if so the flex can be a bigger number and the pole will be softer to bend.
Pole Can Loose Flex
I seen a 460 20.0 to to a 20.5 when bent to 90 degrees once and then bent 99 more time and end up a 21.0. That's a 5 pound loss in stiffness at that length.
Other data support the same conclusions when testing new poles then the same pole at a later date.
Other data support the same conclusions when testing new poles then the same pole at a later date.
Eddie Seese
P. O. Box 544
Youngtown, AZ 85363-0544
(623) 972 4666
P. O. Box 544
Youngtown, AZ 85363-0544
(623) 972 4666
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- PV Beginner
- Posts: 23
- Joined: Sat Oct 21, 2006 11:50 pm
Flex Number don't track
Flex number are only for a lenght. the 12 ' pole is 10 pounds stiffer at the same grip as the 11' 5" pole.
Eddie Seese
P. O. Box 544
Youngtown, AZ 85363-0544
(623) 972 4666
P. O. Box 544
Youngtown, AZ 85363-0544
(623) 972 4666
Measuring Change in Flex
Well, all the manufactures do it differently but for your own records try this. You can also use this to get relative stiffness between poles of different lenghts by using the same suspension points.
Suspend the pole 6" from the botton and 12" from the top. Hang a 50 # weight in the center of those suspension points and measure the deflection in cm. Do this in the shade.
Suspend the pole 6" from the botton and 12" from the top. Hang a 50 # weight in the center of those suspension points and measure the deflection in cm. Do this in the shade.
Eddie Seese
P. O. Box 544
Youngtown, AZ 85363-0544
(623) 972 4666
P. O. Box 544
Youngtown, AZ 85363-0544
(623) 972 4666
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