Go Back  HuntingNet.com Forums > Archery Forums > Technical
Too Stiff a spine theory exploration >

Too Stiff a spine theory exploration

Technical Find or ask for all the information on setting up, tuning, and shooting your bow. If it's the technical side of archery, you'll find it here.

Too Stiff a spine theory exploration

Old 09-23-2002, 08:01 AM
  #21  
Nontypical Buck
Thread Starter
 
Join Date: Feb 2003
Location:
Posts: 2,994
Default RE: Too Stiff a spine theory exploration

Jeff, I saw that in your first post. The link on Lancaster said terminator select, if I get some I'll double check that they are indeed selects.

Just for fun, I bought a heavy terminator at Walmart. One of the .006" straight ones, but I was curious to see how it left the bow. It was only $5 or so...

At ten yards (max I can shoot inside where my bow was, no time yet to do more testing), it hit's about an 1" lower than my 350 grain GT 5575. Really didn't notice a big difference in the quietness of my bow when shooting it, and not much difference in reduced shock either. I was expecting more noticeable effects from shooting a heavier arrow.

No way to test penetration, plus I was just shooting field tips, but the lighter faster arrow seems to hit the target with much more authority. Not sure what that translates into in the real world, but for this season I feel confident sticking with the set up I've got.

I love saving money

Rangeball is offline  
Old 09-23-2002, 12:54 PM
  #22  
 
Join Date: Feb 2003
Location: Florence AL USA
Posts: 53
Default RE: Too Stiff a spine theory exploration

Rangeball,

I'm going to throw another opinion out at you...

First off, I didn't read all the responses, but I did read several mis-statements of information that might have confused you. Your theory, and the impressions you have gotten from Ragsdale, are pretty much correct.

If we could load telephone poles into our bows and shoot them, they would NOT flex during the shot. Most arrows, not being telephone poles, (even the stiffest) will flex during the shot, but only by an amount proportionate to their spine. So, if you get an arrow that doesn't flex much (like you're trying to do), that arrow is capable of translating a higher amount of force into forward velocity and wastes less energy on flexing (movement of the shaft in any direction other than straight ahead.) Like you said, since it doesn't flex much, it won't deviate much from the initial path.

The DIRECTION that an arrow flexes can depend on several things, but they are all created by ONE THING: THE ARROW'S POINT LOCATION IN RELATIONSHIP TO THE DIRECTION THAT THE NOCK IS BEING PUSHED.

Left and right flexes (tears, etc.) are considered spine related only when the tail (nock) of the arrow is pushed to the side. This can come from a finger release, rope releases, etc. If you have a "straight ahead" release (caliper/loop), and your center shot holds the point directly in the (left/right) path that the nock will travel, then the tears and arrow flex will be up/down. {Left/right tears can also be torque related, but that does not apply to this discussion.} The Easton guide applies mostly to finger release situations (even though it says otherwise.) This is directly from Bob Ragsdale, whose son (-in-law?, maybe) helped right the damn thing. It's not a bible. At the end of it, it says, "The exact opposite adjustments to those mentioned may be necessary", or something like that.

In a straight-ahead release, the arrow would not flex AT ALL 1) if it were stiff enough to absorb the load of the bow, which we've already decided with your super-stiff carbons we can basically do and 2) if there were no up down movement of the nock during the shot. The up/down movement is basically the path that the nock point on your string takes as the string is "reeled back in." Ragsdale says there is ALWAYS, ON ALL BOWS, some degreee of difference in the exact amount being taken up by the top in relation to the bottom of the bow at each point during the shot.

A "too stiff" arrow WILL NOT have to recover (and lose momentum, as was stated by someone), if the centershot and nock point settings were correct. Allowed to leave straight, the stiff shaft will result in more velocity, etc., because less energy is wasted in flex. (The only reason that there might not ACTUALLY be more velocity is the drawback that Ragsdale mentioned: stiffer arrows generally mean thicker walls = heavier arrows.)

I completely disagree with not tuning the bow to match the arrow. Spine is just as important in carbons as it is aluminums. It's just that the manufacturers have presented FEWER shafts to cover a WIDER range. It DOES NOT MEAN they are all properly spined at any length. (There used to not be as many aluminums as there are now. Does that mean the all these other sizes weren't needed?) It is naive to think that because you picked your arrow out of the right size chart and have the right point weight on it , that it is perfect for your "perfectly tuned bow". It may be close enough to be acceptable, but I could almost guarantee it's not perfect. It's much easier to turn a fraction out of your limb bolts than to go have 1/4" cut off all your arrows, but hey, that's just me. The problem is once you get them back and discover that it should have just been a 3/16" adjustment, it's hard as hell to add 1/16" back to the shafts. But, then again, maybe I'm not as good a guesser as some folks.

For me, these are the "nuts and bolts":

a) I want to shoot fixed broadheads well.
b) Fixed broadheads fly best on properly spined or over-spined arrows. WHY? Because the only time the broadheads "pull" the flight of the arrow off course is when they turn sideways to the direction of movement. This amount of "sideways time" is maximized on a flimsy shaft (flexing a high amount and for a longer time) and minimized on a stiff shaft (flexing very little and not for very long.)
c) The best way for me to determine proper spine is bare shaft testing. An adequately spined arrow (w/ field point) can be shot accurately at reasonable distances, once the centershot and nock point are close to proper settings. There is NO interpretation of tears. You can accurately measure how adjustments change the relationship of bare shafts to fletched ones on the target. Once your two groups are close, you can back up and gain an even finer adjustment. (Just the opposite with paper tuning, because the farther you back up, the more you get LIED TO.)

Simply put, once I get my bow tuned to the arrows, so that the arrows are properly spined (stiffer is better, but once I reach the point of same impact, any stiffer is futile), I know I'm not far from being able to shoot any fixed broadhead.
CapstoneME is offline  
Old 09-23-2002, 02:49 PM
  #23  
Nontypical Buck
Thread Starter
 
Join Date: Feb 2003
Location:
Posts: 2,994
Default RE: Too Stiff a spine theory exploration

Capstone, are you saying I'm right

Thanks for taking the time to respond. You put into words all the jumbled thoughts in my head. THAT makes perfect sense to me, and narrows down my search even more.

Rangeball is offline  
Old 09-24-2002, 06:00 AM
  #24  
 
Join Date: Feb 2003
Location: Hilliard OH USA
Posts: 328
Default RE: Too Stiff a spine theory exploration

Thanks Capstone!
Rangeball it looks to me as we were thinking along the same lines.
I would like to see a high-speed video or arrow flight out of a test rig with a large number of arrows(different styles and spines) using a zero-effect rest(or similar style) to see just how dramatic the difference in spine is.

Great Thread all!


Greg

"Getting close to the game is the joy of Bowhunting for me, the harvest is a bonus."

Live 15 ft Python after eating a small Antelope!
amosgreg is offline  
Old 09-24-2002, 07:32 AM
  #25  
Nontypical Buck
 
ijimmy's Avatar
 
Join Date: Feb 2003
Location: WEST PALM FLORIDA
Posts: 2,890
Default RE: Too Stiff a spine theory exploration

Capstone so what you are saying in essence is you cant have too stiff a spine if you are shootin a caliper type release , and that if your centershot and nocking point are close that you should not get left-right deviations, if you dont tourqe the grip . I dont agree with that as I think everybody tourqes the grip, some worst that others, but everyone does , so the quest is to find the arrow that shoots the most accurate for you ,and I dont think that will be the stiffest arrow you can find .

"Simply put, once I get my bow tuned to the arrows, so that the arrows are properly spined (stiffer is better, but once I reach the point of same impact, any stiffer is futile), I know I'm not far from being able to shoot any fixed broadhead."

Insteed of the word futile I think detrimental would have been better just my $.02


If information provided by the members of this board have helped you please let us know .

Edited by - ijimmy on 09/24/2002 08:34:37
ijimmy is offline  
Old 09-24-2002, 07:54 AM
  #26  
Nontypical Buck
Thread Starter
 
Join Date: Feb 2003
Location:
Posts: 2,994
Default RE: Too Stiff a spine theory exploration

ijimmy, grip torque is mostly an issue with fixed prong rests. I use a drop away, so it is a moot point.

Also, I do not grip my bow, simply pull it back into the v web of my thumb and forefinger, let it settle where it wants, and release.

Unless you are torquing the bow in the exact same way everytime, your selected spine will react differently upon each shot. I'd much rather work on my form and technique than keep trying new arrows to chase an ever changing problem.

Rangeball is offline  
Old 09-24-2002, 08:01 AM
  #27  
Nontypical Buck
 
ijimmy's Avatar
 
Join Date: Feb 2003
Location: WEST PALM FLORIDA
Posts: 2,890
Default RE: Too Stiff a spine theory exploration

Rangeball I understand what you are saying most of the members of this board probably have above avarage form but I think if you would "much rather work on my form and technique than keep trying new arrows to chase an ever changing problem." that getting the stiffest arrow is the wrong advise . I think you would be better served by picking an arrow from the charts by adding 1 1/2"s to your total length . This will put you in a "slightly stiffer spine" not the "stiffest arrow you can find that agrees with the arrrow weight you want to shoot"








If information provided by the members of this board have helped you please let us know .

Edited by - ijimmy on 09/24/2002 09:34:39
ijimmy is offline  
Old 09-24-2002, 09:05 AM
  #28  
 
Join Date: Feb 2003
Location: Florence AL USA
Posts: 53
Default RE: Too Stiff a spine theory exploration

ijimmy,

You make a good point, and I can’t disprove what you’ve said. I completely agree that everyone torques the grip to some extent. The point I was trying to make was that if your release method (caliper, loop, etc.) doesn’t kick the tail of the arrow to the side, spine tears during paper tuning will not be left/right as most tuning guides say. They will, instead, be up/down tears. For an arrow to flex in the left/right plane, there has to be some force acting on it in that direction. With fingers, the string kicks them hard to the side, so the arrow is subjected to a “fishtailing” force. If you have a loop, or a caliper that retracts both jaws from each side of the string at the same time, there is no left/right force; therefore, the only thing that can put a left/right force on the arrow is the rest itself. {Restating what I said earlier, the reason that the flex does occur in the up/down vertical plane is because the force from the string acts on the arrow in that direction. As the string recovers from full-draw back to it’s normal position, the excess that was “let out” is being “reeled in” by the eccentric(s). This creates a “tug of war” between the top limb and bottom limb, and results in the nock point being pulled in an unlevel path, varying with every bow and dependent upon synchronozation or position of the cam(s).}

I think most “natural torque” can be canceled out by adjusting the centershot setting of the rest. That’s one reason I’m such a proponent of tuning your own bow. The grip of the technician at the pro shop is NOT going to be the same as owner of the bow.
CapstoneME is offline  
Old 09-24-2002, 09:17 AM
  #29  
Nontypical Buck
Thread Starter
 
Join Date: Feb 2003
Location:
Posts: 2,994
Default RE: Too Stiff a spine theory exploration

ijimmy, I'm not advocating everyone go out and pick the stiffest arrow they can, I was looking at doing so only to fit a specific purpose- Use a carbon arrow and a heavy weight. I've since found others to fit the bill (Thanks JeffB) so this is less of an issue, but I still stand by my original theory, too stiff a spine will not cause you problems from a well tuned bow with a straight ahead release.

Rangeball is offline  
Old 09-24-2002, 11:07 AM
  #30  
Giant Nontypical
 
HuntingBry's Avatar
 
Join Date: Feb 2003
Location: Phoenixville, PA USA
Posts: 5,541
Default RE: Too Stiff a spine theory exploration

Rangeball, I have had a similar dilemma lately in that I have a fairly short draw length (28&quot and prefer to use carbon arrows. This causes my arrows to weigh less than 400 grains which I would prefer to be over for hunting purposes. I have been considering using weight tubes to get this problem solved. I don't know how this will effect the stiffness of the arrows since I am not making the shaft stiffer, but heavier. It does, however, throw off my FOC and I will have to switch to a heavier head, which will effect the spine. It is something I will experiment with after the season, but should be interesting.
HuntingBry is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Buck_Slayer
Technical
3
08-23-2007 10:21 AM
Bulzeye
Technical
14
03-24-2005 09:40 AM
Dairy King
Technical
3
11-08-2004 05:53 AM
G2 Shooter
Technical
34
11-04-2004 05:17 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Quick Reply: Too Stiff a spine theory exploration


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.