# How off would the tension be with a +/- 10 degree drop weight arm angle?

Discussion in 'Stringing Techniques / Stringing Machines' started by flargosa, Feb 21, 2013.

1. ### flargosaNew User

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How much tension variation within +/- 10 degree angle of the drop weight arm? Just wondering, cause I usually string my poly at 52 lbs with a not so horizontal drop weight arm on some pulls.

Last edited: Feb 21, 2013
2. ### rich sHall of Fame

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the variation would be +/-1.5% of the selected reference tension

your tension applied would be as low as 51.2# at +/- 10* from horizontal.

EDIT..... the variation would be +0/-1.5% not +/- 1.5% as the tension cannot be higher than the reference tension.... the tension only goes down as the bar deviates from horizontal.

Last edited: Feb 22, 2013
3. ### darklore009Professional

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shouldnt worry about it too much. it's off by a small percentage. not a problem at all

4. ### flargosaNew User

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Ok so +/-1.5% that is about 3% difference between the highest to lowest tension. Seems perfectly acceptable. Thanks.

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6. ### IrvinG.O.A.T.

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Trig was a long time ago but cosine = adjacent side / Hypotenuse.

Cosine 10 = 0.839

Adjacent is the length of weight from pivot

Hypotenuse is the length it should be for true reading

Therefore your are about 16% off. Stringing at 52 lbs you would end with (tension = 0.839 x 52) about 44 lbs tension.

EDIT: You are much better off if you can keep the angle under 5 degrees then there is little error at all.

Last edited: Feb 21, 2013
7. ### rich sHall of Fame

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Irvin not sure if you hit the wrong button on your calculator or looked at the wrong column in a trig table but ... cos10 = .9848

.985*52 = 51.2#

cos^-1 (.839) is something like 33 degrees....

unless you looked up the cos of 10 rads as opposed to 10 deg?

rich

Last edited: Feb 22, 2013
8. ### IrvinG.O.A.T.

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Oops I didn't use a calculator I used the Internet. I use the cosine 10 when I should have use the cosine 10 degrees. My bad. But still you are much better off keeping the angle under 5*. At 5* (cosine 5 degrees = 0.996) your error is a max of 0.2 lbs where 10* is 0.8 pounds.

Not sure where this 10 degrees is coming from though. I know the Gamma X2 uses a ratchet with 36 steps I think that give you 10* (360/36.) But if you are let's say -8* below level and you take it up one step you should be around +2* so there should not be a problem getting under 5*. Or am I just wrong again? LOL

EDIT: BTW thanks for catching me on that Rich

Last edited: Feb 22, 2013
9. ### rich sHall of Fame

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No problem Irvin...

10. ### flargosaNew User

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Thanks really glad to know +/- 10 degrees is still within acceptable range to me. Now I can worry less getting that arm perfectly horizontal knowing the tension variance very little.