Author Topic: Tapering shafts  (Read 3281 times)

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Offline feathersnwood

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Tapering shafts
« on: November 14, 2018, 08:25:32 pm »
I’ve got a question if I have a 11/32  30” cedar shaft and it’s 55#spine if I taper it 10” to 5/16 th how much spine would I lose ? I’m wanting my shafts to end up at about 45-50#just wanting a idea on where to start at . Haven’t ever tapered any shafts and wanting a starting point . Thanks
lets get back to the basics

Offline Pat B

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Re: Tapering shafts
« Reply #1 on: November 14, 2018, 08:46:18 pm »
You may loose a pound or two, especially if tapering only the back 10". By tapering the rear you also benefit with better arrow clearance which makes it more forgiving.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline feathersnwood

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Re: Tapering shafts
« Reply #2 on: November 14, 2018, 09:06:19 pm »
Yes I was going to taper the back 10” sorry for not being clear on that thanks I thought I might lose more than that .
lets get back to the basics

Offline Pat B

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Re: Tapering shafts
« Reply #3 on: November 14, 2018, 10:45:21 pm »
When an arrow goes through paradox most of the bending is in the center of the arrow. The ends usually remain pretty rigid.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline TSA

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Re: Tapering shafts
« Reply #4 on: December 06, 2018, 07:56:06 am »
on 11/323 sitka spruce, when we taper the back 8" we lose  zero in spine( or at least less than 1#). when we taper the back 9" we lose about 1 pound in spine.
i would imagine its more of a proportional thing, related to the beginning spine of the shaft, and not an actual figure- but thats what i figure on anyway.
So That ties in with Pats points above.
« Last Edit: December 06, 2018, 11:57:42 pm by TSA »

Offline feathersnwood

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Re: Tapering shafts
« Reply #5 on: December 11, 2018, 03:35:40 am »
Thanks guys I tapered two and one I lost 1 lb spine and other stayed the same . Thanks for the help I was worried about this for some reason didn’t want to waste some shafts if they changed spine a lot !! The one that lost a lb in spine was one of those that was in between to start with. Never shot tapered shafts before but always wanted to try !! Thanks again!!!
lets get back to the basics

Offline Pappy

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Re: Tapering shafts
« Reply #6 on: December 18, 2018, 03:46:44 pm »
I really like tapered shafts don't know why I don't do more  ??? and have found the same thing Wayne said, no change out to 8 inches and roughly a pound for every inch after, most effect on the spine is in the middle 2/3 or so of the shaft, at least that is what I have found. :) Look forward to seeing them finished. :)
 Pappy
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Offline Scyth

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Re: Tapering shafts
« Reply #7 on: December 25, 2018, 09:23:07 pm »
I found a minimal spine difference the net spine, but the dynamic spine was quite different.

It shot straighter with less overt paradox.

That is why I take tapered shafts - despite the hassle - above straight shafts.

My bamboo shafts are another issue.

. . . but shoot a thumb ring and the opposite side of the grip . . .

regards,

Scyth
« Last Edit: December 25, 2018, 09:26:28 pm by Scyth »
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and I will carry on my work a long as I can . . . "

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Offline TSA

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Re: Tapering shafts
« Reply #8 on: January 06, 2019, 09:44:43 pm »
good point Scyth,
we find when we taper from 11/32 to 5/16 over 9" we lose about 10 grains in weight.
so for a standard arrow, with a 125gr point, reasonable fletchings and a plastic nock, due to its foc or balance point it works (according to all the tests we did) out to a ratio of 1: 1.6
in other words for every grain you add to the rear, you need to add 1.6gr to the point to maintain the same foc.
so if you remove 10gr from the rear, its the equivalent of adding 16gr to the point.
so that like going from a 125gr head to a 140 plus gr head. thats a significant improvement in foc, without actually having to add the weight.
its really a win win. you get a lighter overall mass of arrow, with an improvement in foc without actually having to go to a stiffer spine shaft and an increased mass in the arrow.
And as we know, thats better for trajectory and for " paradox" recovery, and the arrow is also inclined to be a bit more forgiving of slight errors in release.

having said all that, there are some negatives to high foc arrows too- but that a whole 'nuther discussion.

i will see if i can find the results of those measurement and tests we did, and post them up here, if anybody would like?