Trad Gang

Main Boards => The Dark Continent => Topic started by: BUFF on March 17, 2008, 10:04:00 PM

Title: need more spine
Post by: BUFF on March 17, 2008, 10:04:00 PM
I made up some Heritage 350 shafts. I added the 100 grain brass insert and the 8 grain per inch weight tubes. I will be using the 200 grain GK head. My problem is they show to be under spined from my 74# bow. which means they are going to be real weak when my 84 gets here... Is there a way to add spine to them? the 350 is as stiff as they offer and they are already as short as I can cut them.
Title: Re: need more spine
Post by: Benny Nganabbarru on March 18, 2008, 02:55:00 AM
Hi Buff,

I really like using 30" CX350s with 300 grains up front out of my 78lb@29" Black Widow PLX longbow. But when I tried that same arrow out of my ~71lb@29" Black Widow SAIII, I had to drop the weight down to 225 grains up front, and then they were only just over the 8 grains per pound mark. But they worked a treat.

So, I don't believe there's any way for CX350s to work for you with that new bow. I've been pondering this for awhile, as I've got a recurve around that weight on the way, too. What I believe will work is the Grizzlystik Safari. I'm also lucky enough to have tracked down some 115lb spined Douglas Fir arrows from Surewoodshafts.com, and I think they'll do good with a 190 grain broadhead. But, they will be just regular animal arrows, not buffalo arrows. Which brings me back to the Grizzlystik Safari, which can be front-loaded right up.

Other alternatives, which Rick McGowan really likes, are aluminium with carbon inside, without a substantial front-load.

Then there are the purpleheart and ipe arrows that I've heard about, but haven't yet found anyone who makes them.

Good luck,

Ben
Title: Re: need more spine
Post by: Dr. Ed Ashby on March 18, 2008, 10:02:00 AM
Marty, try removing the weight tube and adding a section of small diameter carbon shaft back of your insert; securely glued to both the outer shaft's inner wall and the back of the insert. The Beman youth arrow works well.

This not only adds some FOC, it shortens the working section of the arrow, stiffening the dynamic spine. You'll have to work by trial and error to get the dynamic spine just right, but I would suggest you start with a section of shaft about 7" long.

If spine is only slightly weak, you might consider adding a thicker arrow-plate on your bow; moving the shaft away from the bow's center-line a tad.

Ed
TGMM Family of the Bow
Title: Re: need more spine
Post by: Rick McGowan on March 18, 2008, 10:03:00 AM
High FOC arrows from heavy bows, just isn't going to happen. Its one of the reasons I'm not a fan, high foc only is practical for lighter weight bows and carbon shafts. Everyone worries about the heavy bow, but the arrows for the heavy bow are the big problem. The only good reliable solution I could come up with, was a shaft inside a shaft, some combination of carbon and or aluminum. The ones I personally came up with are a carbon inside an aluminum shaft as Ben said, but there are a lot more choices in the carbon shafts now than there was a few years ago.
Title: Re: need more spine
Post by: Dr. Ed Ashby on March 18, 2008, 11:22:00 AM
Rick, I've set up Extreme FOC arrows for trad bows up to 115#, and c-bows up to 90#; with perfect bare shaft flight. Just as with aluminum/aluminum and aluminum/carbon shafts, it takes some work to get them right, but I find them MUCH easier to get perfect bare shaft flight from than the normal FOC double shafts. Extreme FOC with heavy bows is definitely a 'doable'.

Ed
TGMM Family of the Bow
Title: Re: need more spine
Post by: BUFF on March 18, 2008, 12:21:00 PM
Thanks for the Info guys...
Title: Re: need more spine
Post by: Jarrod Feiner on April 21, 2008, 10:59:00 PM
Dr. Ashby,
I learned something vicariously reading this post.

Thanks for the suggestion about building the rest out a bit. I'm in the final throws of fine-tuning arrows and I'll bet that would do the trick.

J