Wood arrow spine question

[jono446]

Hey all I'm diving into the wood arrow world and have some questions. I ordered a spine test kit from surewood with the heaviest spine being 65-70lb. I'm shooting a 50# toelke chinook and I draw around 28.5. With the arrow cut to 30" and 125 grain tip it's kicking tail left fairly hard still, which would mean weak spine correct? Which spine range should I go when ordering my new dozen shafts? And also will staining and sealing shafts increase spine?  Thanks for any help I can get

[frank bullitt]

How is your form and release?

Arrow nock fit?

Type of string, high performance string or dacron?

That spine weight should be good.

[BAK]

Something doesn't make sense.  That arrow should be way too stiff.

[jono446]

It's a fast flite string of some sort and nick fit is really good. I had someone else shoot it to make sure it wasn't just me and he had the same results

[frank bullitt]

Not to stiff for a fast flight!

I'm sure of top quality from Surewood, only thing
else is spine weight of shafts 65 70?
And what or how did you build arrows?
Edge grain to bow shelf?

[dnovo]

Are you shooting bare shafts or fletched arrows?  How is your brace height? Need more info

[jono446]

Yes I was shooting bareshafts, edge grain towards shelf. Brace height right at 7.5

[Pat B]

When you buy wood shafts that are spined at 65-70# they are for a 28" arrow with a 125gr point at 65# to 70#. For a 30" arrow you reduce the effective spine by 5# per inch over 28" so their effective spine would be 55# to 60#.

[Shadowhnter]

Edge grain goes towards shelf? Ive been doing it wrong all these years with face grain on shelf? (Face grain at 12 and 6 oclock, edge grain at 9 and 3 oclock?) I thought the edge grain is where the spine is for the left/right bending of paradox.

[Roy from Pa]

Edge grain is the stiffest.
(Face grain at 12 and 6 oclock, edge grain at 9 and 3 oclock?)
You have it right.

[dnovo]

I don't bareshaft woods. I think if you fletch one up you'll be fine. Fletching will stiffen spine a touch.

[MnFn]

I am shooting 55/60 out of a JD Berry Morning Star 52@28 and probably would do better with 50/55.  70/75 out of a 55# Tall Tines recurve. The TT is pretty quick.

Something Paven mentioned has been true for me. Wood arrows work best for me when the length is as close to the bow as you can get it.

If that arrow truly is too weak you could cut an inch off your arrow.

[BAK]

By the way, edge grain is not always the stiffest, we've just been told that for so many years we tend to believe it.  I've tested many wood arrows and often they are stiffer cross grain.

[frank bullitt]

Correct BAK!

Especially on hardwoods.

But I would assume they were measured on the edge.

My Adams spine tester measures on a 26" supports.

[jono446]

I just went out and did some more shooting and cut the 65-70 arrow down to 29" and it bareshafted good and flew great after I fletched it. Now I'm wondering if I should order a 70-75 to get a 30" arrow?

[flyflinger]

Had similiar results (posted about it a week or so ago). I shoot 49# @28". Surewood shaft 70-75#.  29" OAL w/ 125 up front has me shooting bullet holes on paper. Tune what works best for you and run with it!

[Pat B]

You want the grain "flames" at 12 o'clock and at 6 o'clock pointing forward for safety reasons. Of the two edge grain sides put the stiffer side against the bow.
The AMO standard for a spine tester has uprights placed 26" apart with a 2# weight hung in the middle. The spine measurement is for a 28" arrow with a 125 gr point. This is the true AMO spine standard. Any differences have to be calculated into the formula.

[jono446]

Originally posted by flyflinger:
Had similiar results (posted about it a week or so ago). I shoot 49# @28". Surewood shaft 70-75#.  29" OAL w/ 125 up front has me shooting bullet holes on paper. Tune what works best for you and run with it!

Yeah I thought I was crazy but I'm gonna get the 70-75 spine and point tune if I need to. Thanks for the help I've gotten from everyone!

[Pat B]

For each 25gr of point weight over 125gr you subtract 5# of spine weight.

[frank bullitt]

Cool! Glad ya got figured out.

Shooting wood is gooood!