Where did the idea of spine come from?

When I was a teenager, the 60s, the paint was coming off my Bear cedar arrows, so I decided to refinish them. I was surprised to find that they paid no attention to grain orientation. No wonder some of them flew like crap, even I knew better than that, so I switched to fiberglass, to find that even those had a weak and strong side, so I switched to aluminum.  Later in the 60s I got my own fletching equipment, then I could shoot wood arrows again.
  I just reread Saxon Pope's advice on birch arrows. 3/8" birch, tapered at the nock end, if it is whimpy or if it snaps when you bend it, it is not a hunting arrow. I imagine the history of spine is similar to how golf was invented in Scotland. One sheep herder knocked a sheep turd into a ground squirrel hole with his cane and the other sheep herder dude thought, what fun, so he tried it too. There had to be some sort of trial and error methods for arrows that got less and less archaic over time, until someone said "Screw this there has to be a better way."

[LongStick64]

Historically speaking there were bowyers that make the famous English longbows and they had other professionals that made the arrows and they were indeed professionals. So for their warbows they did have matched arrows. Did they use spine or some other measurement I don't know, but they did take it serious enough to that is was a profession of merit.

[halfseminole]

2" at 15 yards.  That's even three different draw lengths.

I find it interesting that the reasoning from most of the archery manuals that I have read is that if it weighs the same and it has good balance it will shoot.  This was applied to everything from flight arrows to war arrows to target practice.  It's what I have found as well.  Is there a "best spine?"  Probably.  I don't want you to think I don't understand that tuning is necessary-but I'm wondering if one type of tuning is as good as another.  

In making a Turkish flight arrow, a piece of cane (Arundo Donax, giant cane) was split into tiny strips.  Those strips were sorted by size, heat treated, sorted by weight, pared down to a 60 degree angle and reassembled in six strip sections into a hollow barreled arrow.  They were each then graded according to weight, each fletching was weighed and attached, and they were weighed again.  Tips were put on them and nocks were attached, and weighed again.  After all that, if necessary they would drill a hole in the arrow and put lead or mercury in to make sure the weight was exactly even.  

Yes, today's arrows are more uniform and finding the right one is easier.  I find the recreation of historical styles to be most interesting, so that's what I do.  I just sought to understand a concept that I wasn't taught with.

[ddauler]

Interesting topic. I agree matched is better than unmatched. I think spine is more important than weight. That said I have self wood bows that shoot great with a wide range of spine. My method is simple If the arrow shoots good I slap my broadhead on it if it still shoots good and hits the same spot as my field points it goes hunting. My concern is that we are looking for excuses for bad shooting. FORM is the most critical for arrow flight. Picking a spot for acuracy. These are done by the archer not the tackle.

[BowDiddle]

To be honest, I have had several bows (pretty much all of them), that would shoot a wide variety of arrow spine.

The sticker is, the different arrow spines require different tuning with point & length, etc to get them to all fly the same (as in good flight). You end up with a hodge podge mix of arrows of different lengths & weight, that even though they all fly good, they do not shoot the same.

Not my Cup O Tea. I want to know that from arrow #1 through arrow number whatever they will all shoot reasonably the same.

[reddogge]

Interesting topic but I do believe the people of long ago flexed their arrows and had an idea of what flex would work out of their bows. The English warbow was probably more homogenous than the more individualistic bows made by different Native American tribes so the arrow makers could flex a shaft and tell whether it would perform out of an English warbow same as a Native American could do with a cane shaft.

From reading so much history in my life I just think something like spine or flexing of the shafts was one of those things never mentioned as it was taken for granted.

Similar to the mountain man days when a man fired his black powder weapon and reloaded in haste to protect his life. It never gets mentioned how and when he cleaned the rifle. Did he pull the valuable ball thus ruining it to clean the rifle at the end of the day? We know their lives depended on the rifle but you never read about that important chore.

In the civil war and the old west how did they clean their revolvers at night? How did they pull the loads, clean and reload? Never mentioned in any book I read. A very important but mundane task not covered much but you know it happened.

[Gordon Jabben]

I hear quite often "spine is more important than weight" and I don't want to be rude or argumentative but how much weight and spine difference are we talking?  I have always thought that weight was more important than spine within reason such as 30 grains to 10 pound spine in a group of wood arrows. I hope this doesn't come off that I'm just a jerk that wants to stir the pot but weight seems so important to me.  Maybe it's because I shoot at longer distances.

[Krex1010]

Really is an interesting topic, I'm enjoying reading everyone's responses because answering requires some original thought, not just a rehash of old info. I've already shared my thoughts in this thread about how I think archers of the past viewed arrow quality, I think they knew it well. But I also agree with Halfseminole's feeling that their is real value in being able to grab an arrow and be proficient with it, regardless of the quality. I've seen primitive people with very rudimentary bows, shoot smaller, lighter arrows when hunting small game, and then heavy 4 foot in fletched arrows when bowfishing. They don't care if the arrow wobbles as long as it makes meat.  Perfect arrow flight matters more when we are scoring in contests at longer ranges, and when striving for clean quick kills on large game.  Many primitive cultures did not see the need for the quick kill on large game, some would poison the arrows, and some would just arrow an animal in the body and then rely on their tracking ability, neither requires perfect flight.

[Tom A]

I would bet some people knew about spine in ancient times.

The master fletcher with the best flying arrows probably knew to match stiffness of arrows and to use stiffer arrows for heavier bows. Its more than likely thats what made him a "master" and was probably a trade secret.

[halfseminole]

Every test I've translated imvolved spinning the arrow to determine balance.  Many cultures I've studied used bamboo as well, which generally doesn't care as much about spine.  The Manchu used exclusively wood, but there was one single standard for war arrows, and everything from 80# to 240# used the same arrows, which spined well into the 200# range.  

I was always taught to spin them on my thumbnail.  If it wobbled, it wasn't good enough.  If it didn't it worked.  This has been my gold standard in arrow making.  When learning Manchu, the rule of thumb is if you can bend it at all, your bow will either break it or fire it unreliably.  The game is so much different.  Korean archers still don't measure by spine, they order by weight-and they use hundredths of a grain.  Then again, their arrows are bamboo...

There's an awful lot of information on traditions like Turkish, Japanese and Korean archery.  There are whole books on arrow making.  There aren't any points in which they bend the shaft.

 http://www.atarn.org/chinese/making_chinese_arrows/making_arrows.htm

Thought you guys would appreciate this.

[Jock Whisky]

Did archers know that arrows bent around the bow when shot before slow motion photography showed it to be a fact??? Or did they just shoot and discard all arrows that didn't fly to their liking?

I just finished reading Turkish Archery by Paul Klopsteg. In it he mentions the Turks didn't pay attention to it probably because they used a thumb ring. Arrow makers for the Turks were very expert in their field so if it was important to them they would have paid attention.

It seems our 3 fingered release is a main culprit when it comes to paradox and spine. Perhaps that is why we seem to be the only people that have to deal with it.

[Burnsie]

Yeah, but don't forget about spline.

[SELFBOW19953]

Jock, that may be part of it.  Didn't Native Americans "pinch" their arrows on the string?

[**DONOTDELETE**]

Originally posted by ChuckC:
I have thoughts.  The shorter your draw length, the less spine matters.  The bigger (to a point) your fletching, the less spine matters.  The better your release, the less spine matters.  Some bows, usually cut past center, allow more leeway in spine.

That said.  Spine matters.  It has to because of what it is measuring, deflection of a shaft as it passes a bow riser under pressure.  If you don't actually measure it with a machine, you can "measure it" by shooting the arrows in question and choosing those that work well for you.

Remember. . .  if certain arrows shoot left (or right) of the others, and you remember this and aim accordingly, it works !  Same with weight.

ChuckC

This thought has merit...

Try tuning arrows for a woman with a 32" draw with a 35@32" draw weight some time and tell me arrow spine doesn't matter.... btw...good luck finding shafts that are long enough that have the proper spine...

My draw is 30" and not having perfectly spined arrows make a huge difference....

[halfseminole]

Swap to a thumb release and a lot of those issues go away.

The Mediterranean, Flemish and such releases place a lot of torque on the string, driving the arrow into the riser.  The arrow flexes more, so it needs a lower spine to be able to self-correct.  More energy is lost on arrow flex, dropping the kinetic energy of the shaft.

A properly executed thumb release puts much less torque on the string, so the arrow does far less paradoxing around the riser.  With less energy in whipping back and forth, the arrow flight is straighter and spine becomes much less important.  A good thumb release is much like a mechanical release or a pinch grip.  And with only one point of contact, it's easier to clean a thumb release up.

I'll try to find the slow motion camera images of each release.  But the more I look at it, spine is an artificially created handicap-it's a consequence of modern bow design and releases.

[dragonheart]

Once you find that perfect arrow for your setup then spine does not matter...  

[halfseminole]

A shot with a thumb ring.  The arrow barely flexes at all.

 https://www.youtube.com/watch?v=aNI9BG87qcI&feature=player_embedded

With the "modern" releases there is much more paradox, necessitating a lower spine and spine range.

[Jack Skinner]

Something I have noticed from making my own arrow shafts from boards. Anyone can pick up any board of any wood and tell simply by the physical weight of the board that it will make a heavy weight arrow. Example Ash vs douglas fir. I know the Ash will be a heavier (grain weight shaft). With most hard woods this also goes along with a heavy spined shaft. Now I know there are heavy spined doug fir and POF shafts. My thoughts is they come from slow growth, narrow ring trees, and are more the exception than the rule, which is why heavy spine in those arrow woods can somethimes be hard to come by. I use poplar a lot, it can be hit or miss on spine weight. When I rip the board down to half inch squares I can tell right away by the physical weight of the squares if they will spine low or if they will make my weight. I just ripped down a beautiful board the other day perfect grain little to no pin knots, but right away I noticed the light physical weight of the blanks and low and behold I didnt get one shaft above 60lb spine.

My thoughts would be in times before "spine" whether they were doweling or making shafts from reed, or cutting dog wood shoots, I believe anyone with practice could tell by physical weight of the shaft material if it was going to be of good spine. Slow growth small ring material seems to be denser and have more physcial weight. No science here just my gut feeling from making my own shafts.

[halfseminole]

So I pulled out some calculators, graph paper and bows.  In addition, I used a bunch of Newton's formulae and a bit of swearing, and came up with the definitive answer for where spine came from and how to eliminate its necessity.  That said, it's not very easy to eliminate.  It is real world possible, though.

Spine is a consequence of archer's paradox.  This is a given.  But archer's paradox is also a consequence of torque on the bowstring.  The videos I posted above bear witness to the relationship between torque and paradox, but there's more to it as well.

I then had to create a torqueless release.  There are two ways to do so.  One is a mechanical release with a rigid loop so that the string itself is not torqued.  The other is the First Peoples pinch grip, which makes no contact with the string.  There is no rotational torque because the string does not roll off of fingers, thumb or thumb ring.  The arrow at this point can be aimed at the target and the bow moved slightly to the side, and the arrow will not flex around the riser.  If the arrow is in the true center of the riser, it can simply be aimed at the target and released.  Proper arrow flight in this circumstance would be with the stiffest arrow possible, so as to take up and down flex out of the equation, though for all but the limpest of arrows the fletching can more than compensate.

The cleaner the release, the wider the spine tolerance and the stiffer the spine that will give good results.  I normally shoot with a long Turkish ring.  When I switched to a short Turkish style, the string was rolled on the ring less and my accuracy improved.  My experiments with both Shang dynasty and Qing dynasty rings show even better flight characteristics and almost complete spine agnosticism.

I then took my wife's Ragim Matrix out.  Using a three under or split grip, a 1535 was necessary to proper flight, as I expected it to be.  Spine was paramount in tuning.  When I used a Manchu (Qing) ring, I could shoot 7595s just as well.  With a pinch grip my 120# warbow arrows would fly like the 1535s.  Spine is the relationship of string torque to arrow flexibility, and the type of bow, arrow, string and release all factor in.

I'm going to contact a friend to bring a video camera over so I can repeat my experiments on tape.  

Yes, spine is paramount to certain setups.  Other setups may care little to none.  But it's a functionality of total setup, not just release type.  I'll work out my equations and post the results if you guys are interested.

[halfseminole]

https://drive.google.com/file/d/0B1mHN1Qipp6NSkQ2NWZaSHhGOU0/view?usp=sharing

There you go, most all equations necessary to explain spine and how release effects it.  Took me a little bit to assemble.  It's simply my gathering together of the necessary equations to explain the effect of release torque on arrow flight.  I plan to add videos when this weather cleans up.