Trad Gang

Main Boards => PowWow => Topic started by: Robert Honaker on November 20, 2008, 06:44:00 PM

Title: Spine...Is it really true?
Post by: Robert Honaker on November 20, 2008, 06:44:00 PM
All I have ever read about, or heard about trad bows ,is that they require weak spined arrows.
I understand that the Easton chart is way off from my own experience, but from what I gather from this site and the other is that people are shooting WAY weaker spines than me. All of my bows are about the same specs....54@28..I draw to 29.5 with a 30in arrow. Most of what I see recommended are 2020,2117 or 400 ...500 spine carbon. I have cut, widdled and played with point weight to madness and always end up with 2216/125gr BH or .350 carbon /250grBH. 400 carbons will work with 85-100gr BH...WAY TOO LIGHT.
If I said I was shootin 2216's with a 125gr BH most people would say I am way off!
I can shoot 2219's with a 175 tip, but don't make me do it, agonizingly slow.
Is all this normal or am I listening to others too much?
Sorry bout the long post.
Thanks
Title: Re: Spine...Is it really true?
Post by: Danny Rowan on November 20, 2008, 07:44:00 PM
If it shoots well out of your bows, do not worry about what other people tell you. IMO for your bow 70/75 spine in a wood arrow would be about right with 125-145 up front. What ever you shoot just tune the arrow to your bow and you will be fine.

Danny
Title: Re: Spine...Is it really true?
Post by: Robert Honaker on November 20, 2008, 07:52:00 PM
See, you underspined me again Danny.LOL.
Ilooked at kelly's chart and it states a 80/85 spine.
I have always wnated to shoot wood, but I'm afraid to buy any cause I know it would mean a month and several purchases to get it right.  :knothead:
Title: Re: Spine...Is it really true?
Post by: R H Clark on November 20, 2008, 07:58:00 PM
The degree of cut to or past center will make a lot of difference.Also your longer draw accounts for more spine.
Title: Re: Spine...Is it really true?
Post by: O.L. Adcock on November 20, 2008, 08:49:00 PM
"The degree of cut to or past center will make a lot of difference.Also your longer draw accounts for more spine."

Yep, plus many don't know what good tuning "is" and say they are well tuned when they are not....O.L.
Title: Re: Spine...Is it really true?
Post by: Outwest on November 20, 2008, 09:06:00 PM
My setups are about the same as yours and I shoot 2216 and 2117. They fly really well.

John
Title: Re: Spine...Is it really true?
Post by: JRY309 on November 20, 2008, 09:24:00 PM
I think most charts are just guidelines they are not carved in stone and there are alot of variables in trad bows and individual shooters.
Title: Re: Spine...Is it really true?
Post by: Robert Honaker on November 20, 2008, 09:27:00 PM
I think I'm well tuned.
I have used the bareshaft method as well as the FP to BH method. I also use the " does it fly straight and hit where I'm looking" method.
If it doesn't fly straight and true I won't hunt with it. I've been killin' a bunch of deer, that must mean somethin'.
But I must say that I always think there's room for improvement. I can never stop tinkerin.
 :rolleyes:
Title: Re: Spine...Is it really true?
Post by: O.L. Adcock on November 20, 2008, 11:18:00 PM
Robert, Didn't mean you were not tuned, just a general observation. You like to tinker? Increase the thickness of your side plate 1/16" or so and retune and see what spine/size it likes. For any given bow you can tune it a good plus or minus 10 pounds or more in spine if you are willing to do what it takes to do so. At 30" a 60# bow tuned to shoot 70-75# arrows will be more forgiving to our errors then the same bow tuned to shoot 80+. What arrows we shoot are our choice, the charts are just a middle ground starting point.....O.L.
Title: Re: Spine...Is it really true?
Post by: Shawn Leonard on November 20, 2008, 11:26:00 PM
I have to agree with OL. I attend some shoots and have a big hunt I host each year with upwards of 70 people and it is shameful to see what most people call good arrow flight.  I shoot carbons mostly and all I need to tune most any spine of them to my 50-55# bows is different point weights. I do not kow what ya mean by needing a light spine for the arrow to tune well. I do know that i like my bareshafts to spine ever so weak cause when i add feathers and a broadhead it acts to stiffen them ever so slightly, Shawn
Title: Re: Spine...Is it really true?
Post by: Robert Honaker on November 21, 2008, 03:05:00 PM
O.L., no offense taken.
Are you saying that a bow that isn't cut to center is easier to tune? Or is it more forgiving  if it's tuned?
Title: Re: Spine...Is it really true?
Post by: SCATTERSHOT on November 21, 2008, 04:57:00 PM
2216 and 2117 are about the same spine (83# vs. 81#). If they fly well for you, from your bow, then you are there. Don't worry about the spine charts.
Title: Re: Spine...Is it really true?
Post by: O.L. Adcock on November 21, 2008, 06:17:00 PM
Not any easier to tune, just more forgiving when done. The kicker with Scattershot's 2216 and 2117's being so close in spine, the 2216 is 1/64" further from center so they won't behave the same...O.L.
Title: Re: Spine...Is it really true?
Post by: Lewis Brookshire III on November 21, 2008, 07:00:00 PM
Why exactley would a tuned bow not cut to center be more forgiving than a tuned bow that is cut past center??
Title: Re: Spine...Is it really true?
Post by: SCATTERSHOT on November 21, 2008, 07:14:00 PM
Not to pick nits, but wouldn't 1/2 of 1/64" be 1/128"? I sure can't shoot well enough to pick up the difference! LOL!
Title: Re: Spine...Is it really true?
Post by: O.L. Adcock on November 21, 2008, 09:03:00 PM
Scattershot, Have you ever shot a bow with a plunger button? 1/4 turn on those things makes a big difference in arrow flight and that's way less then 1/64". The "22" and "21" part of 2216 and 2117 is the diameter in 64ths. Unless you use a thinner side plate that's how far you moved the arrow centerline.

Lewis, the closer to centershot a bow is, the stiffer spine the bow needs, the stiffer the spine the less it bends, the less it bends the lower the clearance from the bow. Our screw ups more easily cause arrow contact. Being cut past center is a good thing only from the standpoint it gives you more options to adjust it in or out, that doesn't mean it should be shot that way. Even Olympic target archers do not shoot their bows "centershot"....O.L.
Title: Re: Spine...Is it really true?
Post by: Greg Owen on November 21, 2008, 09:32:00 PM
O.L.,

I think what Scattershot is saying is that the 1/64th difference is in diameter. So the radius is only 1/128th different - meaning the arrow would be out 1/128th of an inch further on the 2216. The other 1/128th is on the side of the arrow away from the bow
Title: Re: Spine...Is it really true?
Post by: O.L. Adcock on November 21, 2008, 09:40:00 PM
Greg, Ok, I see what he's saying, it's still noticeable no matter what it is.  :) ...O.L.
Title: Re: Spine...Is it really true?
Post by: Lewis Brookshire III on November 22, 2008, 07:49:00 AM
Ok, that makes sense. I have never had a bow cut past center and I always assumed it would be better. I didnt know Oly archers didnt use the passed center option...interesting.
Title: Re: Spine...Is it really true?
Post by: Doc Nock on November 22, 2008, 11:28:00 AM
I'll chime in here...I bugged po' OL to death years back trying to get the BS tuning method to work... nobody could believe for the low draw weight, the spine weight I was needing.

I was shooting a Morrison (still am) that is cut according to Bob, 3/16 PAST center. I thought that was superior!

This year, striving for EFOC, I couldn't get a high FOC and still spine right... then OL made a comment I think is perfect...

(paraphrased)"...when you have a riser cut to center or past, the arrow comes off the string and doesn't know which way to paradox..."  :)

That made perfect sense to me. (OL knows by now he has to "stupid up" stuff to get me to understand!)  :)  

85% of my shots fly true to form...15% will sometimes show some small barrel roll (my term)but hit with the others perfectly.  Especially when I reduced the fletching size to quiet the arrow. I don't like losing energy to poor flight!

When it warms, I'm into sticking some side plate shims behind my seal skin and see what it does. Might even allow me to get my FOC up to EFOC standards!
Title: Re: Spine...Is it really true?
Post by: Curveman on November 22, 2008, 12:27:00 PM
Yep, plus many don't know what good tuning "is" and say they are well tuned when they are not....O.L. [/QB][/QUOTE]
That would be me!   :bigsmyl:   That's why I always have someone stand behind me when I am tuning and look for what I miss. Some people like tuning-I'd rather be like one of those rock stars who have their guitar tuning done by a roadie and just handed to them!   :D  
That being said, I have been shooting these 545gr 55/75 GT's with all the weight up front. 29" Now, I just bought these woods, 28.5 inches 75-80 in spine with 145 up front. 610gr They both seem to fly great out of my 62# Border Griffon longbow that is not cut to center. Now I'm paranoid though. I think you guys would be going: "Whoa! He's WAY off!"    :biglaugh:
Title: Re: Spine...Is it really true?
Post by: Doc Nock on November 22, 2008, 12:36:00 PM
Curvemean,

I can relate. I don't find arrow tuning to be any "fun" at all! It's sometimes just plain frustrating! Like broadhead sharpening...I do it out of respect for the game...but it is often a pure tedious PnA!  :)

I used to be what might be termed a "arra ho" and had every thing imagineable in my quiver... different types (alum, carbon, fiberglass and wood) in different weights, lengths and spine.

When I did my part...they all hit the same relative place...

When I first started BS testing using that planning method...they were ALL weak...way weak!

That's when the light came on. When I was solid footing, standing up in the yard, I was dead on...but not always from a stand or other contorted field position.  I was in those "tails" of the standard distribution of bow/arrow tune that OL's site speaks to!

I had dozens of folks stand behind me, on steps, on ladders...etc and they'd "never" see the occasional subtle "kick" I thought I saw.

The planning method showed me "WHY" I saw that kick...I must have had a reasonably "consistent" release to get any decent flight from those mis-matched batch of arrows.  That and restricting my shooting to 20 yards! Shooting farther shows so much more...even though I won't take that shot on game..it shows tuning issues better!

So many of my friends, even today, say if they hit where they're looking and fly decent...they're tuned and good!    :scared:  

It's amazing on a simple stick bow, how many li'l things can be tweaked to get that "best" (not just good) arrow flight.

Perception is one thing...duplicatable results can be something else!

I swear by the bare shaft planning method, but it can be a conundrum at times and I have to be shooting well for it to work. I've learned to not just shoot one group, or 5, but on different days before I start messin with stuff.   :)  

Seems I'm the most variable variable in my set up!   :)
Title: Re: Spine...Is it really true?
Post by: aromakr on November 22, 2008, 07:57:00 PM
Let me throw another variable at you. A bow cut 3/16" past center, using small dia. carbon shafts will actually have the center of the shaft past the center of the limb making tuning more difficult, you will have to move the strike plate out some just to achieve center to center (shaft & limb)
Bob
Title: Re: Spine...Is it really true?
Post by: Van/TX on November 22, 2008, 08:16:00 PM
Yep  :) ...Van
Title: Re: Spine...Is it really true?
Post by: Doc Nock on November 22, 2008, 08:27:00 PM
Bob,

I'm shooting the GT5575 and that is about .001 thinner in dia. then a 2018 I used to shoot...so not really THAT skinny, per se.

W/ 5" low cut shield, I get great flight...but when I tried the smaller, quieter, the annomolies started to show up...and I went 3" instead of the recommended 2".

OL put it all in perspective with his statement about "don't know which way to paradox". Just kinda makes sense!  :)