Primitive Archer

Main Discussion Area => Arrows => Topic started by: thomas74p on June 10, 2015, 09:41:16 am

Title: reducing spine?
Post by: thomas74p on June 10, 2015, 09:41:16 am
I bought some #60-65 shafts a few years ago, but since the begining of the year have reduced the weight of the bow 12 pounds because it was just too heavy and not fun to shoot.  i would like to reduce the spine of those arrows instead of buying more. can I lightly sand them to reduce their spine?
Title: Re: reducing spine?
Post by: thomas74p on June 10, 2015, 09:55:18 am
just saw a thread below mine about spine :-[ looks like I should scrape it a bit with a razor then lightly sand ;D
Title: Re: reducing spine?
Post by: Pat B on June 10, 2015, 10:28:21 am
You can lightly sand the center of the shaft to reduce the spine. Or, you can add heavier tip weight; 5# for each 25grs over 125grs.
How long are your arrows. For each inch over 28" you can reduce the effective spine by 5#.
Title: Re: reducing spine?
Post by: Aaron H on June 10, 2015, 10:33:13 am
Pat, so you only sand the center section when reducing spine?
Title: Re: reducing spine?
Post by: Pat B on June 10, 2015, 10:37:00 am
The center is the part that bends. By weakening that you reduce the spine. I've not done this with doweled shafts but probably the center 2/3.
Title: Re: reducing spine?
Post by: PEARL DRUMS on June 10, 2015, 10:37:14 am
It takes very little sanding to really change it. Id sand a bit, shoot and repeat on each shaft until they all left the same. Don't bother measuring anything.
Title: Re: reducing spine?
Post by: Pappy on June 10, 2015, 11:09:03 am
Center 2/3 is about right as Pat said. :)
   Pappy
Title: Re: reducing spine?
Post by: thomas74p on June 10, 2015, 02:58:31 pm
only the center! excellent. just the info I need. my arrows are 25''. I will deffinetly try this. do you think I'll be able to slice the turkey feathers off and reuse them? I'm going to try regardless, don't have enough extras to be wasting any if I didn't need to.
Title: Re: reducing spine?
Post by: DC on June 10, 2015, 03:34:31 pm
I would try one without removing the feathers. Scrape from the feathers forward.
Title: Re: reducing spine?
Post by: Pat B on June 10, 2015, 05:23:45 pm
Thomas, did your 25" arrows come from full length 60#-65# shafts?  If so, your 25" shafts shoot like 75#-80# shafts because for each inch under 28"(AMO standard)you increase the effective spine by 5# per inch.
Title: Re: reducing spine?
Post by: warpath on June 10, 2015, 07:24:25 pm
Doing nock end or barrell tapers will also reduce the spine. This is what I did for the shafts I made for Pearlie. Just ask him how it works. :)

  G
Title: Re: reducing spine?
Post by: Pappy on June 11, 2015, 04:54:10 am
I have found just doing the nock end barrel tapper out to about 6 inches don't change the spine, they will shoot great and more clearance of course won't it doesn't really change the spine, after 6 inches if you tapper on up the shaft it will change it a couple of pounds for each inch you move up.  :) Just my observation and also what I was told by the guy that gifted me the tapper jig, it seem to work out about like he said it would. :)
  Pappy
Title: Re: reducing spine?
Post by: warpath on June 11, 2015, 07:41:23 am
Pappy- I agree completely. When I do my nock end tapers, I usually taper the whole shaft unless otherwise requested. Also depends what the shaft's spine is to start with and what the desired spine is.

  G
Title: Re: reducing spine?
Post by: Pat B on June 11, 2015, 08:17:26 am
Adding a rear or full length taper to a doweled shaft allows the shaft to act like a cane or hardwood shoot shaft by making it more draw weight tolerable. It think it is more weight tolerant than spine reduction although the full taper will reduce the spine some.
Title: Re: reducing spine?
Post by: Pappy on June 11, 2015, 10:12:25 am
Yep, my thoughts also, I don't tapper a lot but should do more it really does make them easier to match up with your bow. :)
  Pappy
Title: Re: reducing spine?
Post by: thomas74p on June 11, 2015, 10:42:17 am
pat-b the shafts are surewood tapered shafts. real nice stuff. can't let these just sit and be over spined. I shouldn't have bought such a heavy shaft. but live and learn huh!
Title: Re: reducing spine?
Post by: Pat B on June 11, 2015, 12:15:31 pm
 I don't know about Surewood shafts but with other commercial wood shafting the spine is for a 28" arrow with a 125 point up front.
 Again, for each inch under 28" the arrow will fly like a shaft that is 5# heavier per inch.
You may want to contact Surewood to see how cutting the shaft affects the spine.
Title: Re: reducing spine?
Post by: thomas74p on June 11, 2015, 03:37:32 pm
he asks what length you want and he cuts em for you. I'm assuming he knows what all you said and uses a slightly lower spined shaft for mine since he knows he is cutting them a bit short. I guess I'm a noob when it comes to all the finer details of archery and certainly a noob when it comes to tuning arrows, but his shafts sure seem nice to me.

my idea is to find the center of the shaft by balancing the arrow on my finger and scrape and sand 4 inches in front and 4 inches behind that spot. how does that sound?
Title: Re: reducing spine?
Post by: Pat B on June 11, 2015, 04:57:21 pm
I'd do it in the physical center of the shaft and not the balanced center.
Title: Re: reducing spine?
Post by: thomas74p on June 12, 2015, 09:31:45 am
thanks Pat. I was thinking about that last night while slicing my feathers off. started thinking that idea sounded wrong. I knew you or someone would set me straight. I'm starting to learn to ask first before doing something new.
Title: Re: reducing spine?
Post by: Pat B on June 12, 2015, 10:58:24 pm
Usually with this simple archery it doesn't necessarily pay to over think things. The K.I.S.S. rule rules.   ;)
Title: Re: reducing spine?
Post by: thomas74p on June 19, 2015, 04:11:21 pm
I tried the bare-shaft tuning method this week and sanded the center of the shafts untill each one struck the target perfectly straight on several occasions. some needed to be shot upside down from what they originally were. but in the end I now have all 12 sinking perfectly straight. just got to re-stain the shafts and do a little painting and water sealing then re-fletch and I will take em for a test ride. I'll post up how they do at the range.
for those who have not done this before, I didn't sand very much off. they only dropped about 10-15 grains in weight. so if you try it, don't sand too much and shot each one several times in between sanding so you don't go too much. luckily I didn't screw this one up. of course I haven't shot the final product yet either ;)
Title: Re: reducing spine?
Post by: Stixnstones on July 12, 2015, 09:31:10 pm
Would the sanding the middle method also work on bamboo 'mater stakes?
Title: Re: reducing spine?
Post by: Pat B on July 12, 2015, 10:58:13 pm
I think scraping is the preferred method for cane.
Title: Re: reducing spine?
Post by: Pappy on July 13, 2015, 07:42:00 am
I scrape them lightly for fine tuning but usually just try and leave them longer. :)
   Pappy