can any of you guys describe you you tune wood arrows? can ou bareshat tune them? how do i know what spine i need for a 50- 55 pound bow?
You can bareshaft tune woodies, but I don't, and wouldn't recomend it. Especially while you're new to 'em, and still working on form. Tried it a few years ago, and haven't since. 90% of my tuning is by eye. Shooting a broadhead from 20 yards or more tells me plenty. Once in a while I'll shoot a few holes in paper (with field points) if I want to get technical.
Spine will depend on your bow design, depth of center cut, your draw length, desired arrow length, and preferred point weight. String type matters a bit also. If you know those specs, we can get you mighty close for spine.
i heard that point weight is usually not as high as carbons with wood is this true?
If you know your actual, correct draw length/weight you can figure: shooting 125 gr. points on an arrow 1" longer than your draw length (to clear the back of the bow), to your bow weight add 5 lbs. spine for each inch you draw over 28", subtract 5 lbs. for each inch under 28" of course. If you shoot a "fast flight" string add 5lbs spine. If your bow is cut close to center add 5 lbs. An example: with 125 gr. points on an arrow 30" throat of nock to back of point, a 52lb @29" bow with fast flight string cut to center would make 65-70lb spine a good starting point. (52lbs plus 5lbs for 1" over 28", 5lbs for fast flight string and 5lbs for being cut near center). Concerning point weight, a 35 grains heavier point, in this case 160grains would call for another 5lbs of spine or 70-75lbs.
ok so the spines are based on a 125 grain head? how many gpi are woodies?
No they are not, the spine range needed simply increases/decreases a 5lb range with roughly a 35 grain change of point weight. The grains per inch weight of wood shafting varies somewhat batch to batch in the same wood and quite a bit with different woods. I shoot a lot of Surewood Douglas Fir and in the 65-75lb spine range and they commonly weigh 14 to 15 grains per inch. There are other soft woods that weigh less and some of the hard woods weigh a good bit more.
GPI, or GPP, will vary with different woods, and also vary in different sets of the same wood type. I always figure that and ask for a specific weight range for the shafts. I'll say again: what do you want to end up with?
As far as point weight, you generally don't need a lot to get typical GPP. If you want heavy points, you'll add spine weight. As spine weight goes up, so does the GPI for given shafts.
Here is a link to 3River's Spine chart, for spining recommendations.
http://www.3riversarchery.com/pdf/ArrowCharts.pdf
Wood is a natural material and the densities vary depending on the wood variety and growth conditions and .....
here is a Surewood Link to help with your GPI question for Doug Fir.
http://www.surewoodshafts.com/weight.html
Check out "Arrows by Kelly" website (www.arrowskp) and read his "setup and tuning tips". This will really help you with wood arrows.
so your saying you have 35 grains of point weight to play with ?
I have a barrel full of arrows and when I find one that shoots well with a new-to-me bow I verify it on my spine tester and use that spine of arrow thereafter.
Interestingly - different bows with the same AMO weight prefer different spine weights when shot by me. The window and other factors dictate which is the best spine.
I'm a few months new to wood arrows and no expert but I will share my experience with them. First off I love them. Follow the spine chart Pinky posted and the other advice posted above. Wood arrows are heavier per inch than Aluminum and much heavier per inch carbon. Don't focus on things like FOC to start. Don't worry when your dozen wood arrows you built have differences in weight of 40 grains or even as much as 60 grains. Let it go and try not to think about it. Bottom line is wood arrows seem (to me at least) much more forgiving in spine differences and differences in weight. You won't notice these differences unless you think about them. The best shooters I have shot with don't think about it, they get it close based off of a chart make sure they are in the GPP they want then shoot. They then practice with broadheads and adjust as necessary. What I really like about my wood arrow experience is that I had to let go of the things I mentioned and stop "over thinking" things. When you stop thinking so much, you end up becoming a better archer. The only downside I have found about wood arrows so far is when you break one, it's a lot more heartbreaking than breaking a store bought arrow. All that work and it's gone. My advice is just pick a spine, point and length from a chart and dive in, you won't regret it.
how do they adjust for braodheads? this is what im afraid of as im going to be hunting with them
Just like bareshaft tuning. (based off a RH shooter, opposite for left) If your broadheads shoot left of where you aim, it's stiff so add weight to the point end. If they shoot to the right, they are weak then cut the shaft 1/4" at a time until they are where you like. I think you will find they will be pretty close to the advice and charts. Jim posted the formula above and it works, wood is much more forgiving than other materials, you will be very surprised. I am currently using only dacron strings to keep things simpler and I draw to 28.5. Remember, it's a primitive sport, some of us (including myself, definitely including myself) over think things, the folks that invented archery and used it for thousands of years did not have to be rocket scientists.
You are getting a lot of good advice here.
Have shot mostly wood arrows for the last sixty years, so I am going to comment on what works for me.
Bob Lee Bow, cut past center, 43# at my draw 29"
Tapered cedar shaft, 30" to back of head, 62# spine,
125 gr. head plus 75 gr. woody weight
This arrow with NO feathers shoots very good up to 20 yards.
With five inch shield cut feathers, shoots perfect.
String is D97, but don't think that makes a big difference.
(14 strand)
nhbuck1, what I mean is that if you have an arrow combination, let's say with 65-70lb spine that is shooting well for you with a 125 gr point and you want to shoot 160 gr points you would increase the spine of the arrow to 70-75lb. And it's an approximation, it would apply to a 25 grain change in point weight pretty well too. If paper-tuning, which works well and you need to fine-tune and arrow that is just SLIGHTLY off, say a tear under an inch, you can change strike plate thickness, thicker for spine weak (a tear to the left) and thinner if possible for spine stiff (a tear to the right). You can also change your brace height slightly, increase your brace height with a few turns on the string for an arrow that is indicating SLIGHTLY stiff or decrease your brace height again by a few turns for an arrow indicating SLIGHTLY spine soft in the paper. If your tear is up or down that is an indication of nock height placement on the string, there are numerous good instructional videos you can watch concerning all this by the way.
so if judging bareshaft tuning just on flight if form is an issue what is the next best way to tune?
I think if you read the posts so far, and certainly if you do a simple search, you'll find loads of advice, should you choose to try any of it.
Might make sense to go back to the initial inquiry, tell us your actual specs and preferences, find the consensus on spine, actually get and shoot some arrows... before overthinking tuning an arrow you don't have yet.
Just a thought.
As someone new to wood arrows you gentlemen gave me something I can understand and go forth and build a proper wood arrow with.... thank you