Allowances for Bare shafting

[matt61]

What do you do once you have bare shafted a carbon arrow and got it flying right.
How do you work out how much more to be cut off to allow for the weight of a
wrap and feathers.
I know adding a nock adapter of 8 grains and a Marco trad nock makes the arrow indicate to soft a spine
compared to a Uni-nock on its own.
thanks
Matt

[Mick Smith]

Matt, If you owned a set of accurate scales, I suppose you could weigh the fletches, wrap and extra nock weight separately and you could then add that exact same weight to the rear of your shaft temporarily and then continue with your bare shaft tuning with the added weight. Perhaps you could temporarily add the extra weight to the inside of the push on nock somehow. Some lead shot, held in place with some glue tack, for example.

If you add extra weight to the point end of the shaft, it has the effect decreasing the dynamic spine, so I would have thought if you added weight to the rear of the shaft it would do the opposite, which is increasing the dynamic spine. If I'm right, you would have to cut slightly less off your shaft, not cut more from it. The best way to test it would be to just go ahead, carefully bare shaft tuning all the way and let that process tell you what's going on.

[matt61]

Thanks Mick that's a good idea and I have grain scale. I saw a post on another forum where they added the weight to the tail end of an arrow using duct tape.
But that was for a compound bow with a drop away rest, won't work for a trad bow though.

Maybe glueing a bit of wire of the same weight as the feathers, wrap and nock adapter in side a uni -nock
Matt

[littlejohn59]

Hey Matt
A featherless arrow shaft should fly slightly weak or slightly right of where you aim (for a right handed person or left of where you aim for a left handed person)

Adding fletches and wraps stiffen the shaft making the arrow shoot slightly left when compared to an unfletched arrow for a right hander and obviously the opposite for a left hander.

So don't have the arrow flying exzactly where you want it to when bare shafted. As the feathers and wrap will stiffen the arrow and alter the spine once added to the shaft.

[Stu Ballz]

This is great info good thread

[greybeard]

What do you do once you have bare shafted a carbon arrow and got it flying right.
How do you work out how much more to be cut off to allow for the weight of a
wrap and feathers. ....

I was under the impression that bare shaft testing was the 'Holy Grail' of tuning but obviously not.

Why not make up a full length arrow with wraps etc and start reducing the length until you get the correct flight?

Daryl.

[Mick Smith]

Now come on Daryl. Be nice. I'm sure Matt will end up with a set of arrows that perform beautifully and bare shaft tuning will have played a major part in obtaining those results. Matt is just being very thorough.

I'm guessing the reason Matt didn't fit his wraps onto his shafts prior to his bare shaft tuning comes down to the fact that when he reduces the length of his shafts, he will almost certainly make the cut from the nock end of the shaft and he won't want to cut his wrap. He will make the cuts from the nock end because it makes more sense to glue the point insert into place and then it an easy task to simply pull a fiction fit nock out before making the cuts. It's easier to do it that way.

[matt61]

Just out in the shed setting up to bare shaft some Goldtip 1535's that I have bought to try for my Cascade 53# longbow.
I weighed up all the bits that I will put on the back end of the finished arrow and came with a figure of 31grns.

So thinking outside the box about how to weight up the nock from 12grns to 31grns I have found that a couple of .177 air rifle slugs will punch into the hollow in the Uni-nock schnizeandtight fit and a dab of glue to make sure they stay in there.
VOILA-31grns. Now to see if it will work.
Matt

[Mick Smith]

Am I reading that right Matt, 15-35 GTs for a 53# bow? They're gunna be short arrows.

Have you started to bare shaft them yet? If so, how did they go?

[matt61]

Yes Mick you are reading right, but I am only drawing 48# and going by the carbon arrow chart on the 3Rivers site.
I should be shooting 600 spine arrows, so I bought some Goldtip 1535's 600 spine to see how they will go.
I had been shooting 3555's 500 spine, but there was nearly 5 inches out past the riser with them, after bare shafting a 1535 Goldtip I ended up with only 2 inches out past the riser and 40 grns lighter arrow and it seems to shoot a lot better.
Matt

[Mick Smith]

I'm on the verge of having to go the opposite way Matt. My 35-55 GTs bare shafted beautifully with my 45# Whip when cut to almost exactly to 28 inches. This allowed about an inch of overhang at the front of my bow when at full draw. Now that I've been including back tension as an everyday part of my form, it's added nearly an inch to my draw length, which is now making my arrows a bit on the short side, but not only that, I find they're now slightly under spined, with definite shooting slightly to the right with the nocks angled to the left, a classic under spined scenario. This is with fletches on. I suppose I have two choices, either go for points that are lighter than my 125g ones, or make up some new arrows using heavier spined shafts. I have adjusted my brace height to make it slightly lower and this has worked to the extent that I can still use my 35-55's as they are.

I probably should buy some .400 spine shafts and make them up using some heavy inserts. They would have to be long, I imagine, to bare shaft well. It's probably better to have your arrows too long, rather than too short.

[matt61]

What draw weight do you actually draw with the Whip Mick, I suggest finding that out before you decided on different shafts.
I personally and steadfastly shoot 125grn points/ broadheads only and that's my.... KISS.... philosophy.
Matt

[Mick Smith]

I've got no way of measuring it Matt, but seeing as my draw length is 28 inches, I'd say it would be 45#, the same as what the bow's specs are.

As a matter of interest, I went out to the club range today and my old 3555s shot really well over a variety of distances. There can't be too much wrong with them, I think.