Primitive Archer
Main Discussion Area => Bows => Flight Bows => Topic started by: DC on September 22, 2020, 11:44:30 am
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I was reading over Alan's bamboo strip arrow build-a-long this morning. Fascinating stuff but one thing kept popping into my head. Why does this method produce better/stiffer arrows than just using a bamboo cane of the same diameter? It just seems like you're disassembling a cane and then gluing it back together.
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Ah, you leave out the hole. The hole is very floppy, unless you can get special stiff holes, but they are hell's own job to fit ;)
Del
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The devil's own design? >:D (lol)
Hawkdancer
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They can be barreled and have the node sections staggered. Plus the glue lines provide stiffness.
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OK, so wayne, the previous arrow section sponsor, that manufactures hex shafts from hemlock doug fir spruce etc, claims better spine for a hex shaft over a comparable arrow made from the same wood in normal process.
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I double-tapered the strips so it would form a barreled arrow. Tonkin cane has a higher elastic Modulus or stiffness than any wood, so it should theoretically be possible to make a same-stiffness arrow that is slightly less diameter than a wood arrow. The downside is that it requires precise work in order to get the wall thickness just right. If the strips are too thick the arrow will be too heavy, or have to be made so thin that it is no longer stiff enough. In recent years, I have seen arrows made from some exceptional Douglas fir that is just about as good and a lot easier to make. The hard part is finding these super boards.
Alan
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Ah, you leave out the hole. The hole is very floppy, unless you can get special stiff holes, but they are hell's own job to fit ;)
Del
I still have those used holes for sale from when I bought that dry oil well in North Dakota and pulled the hole out of the ground. The holes are cut in 36" lengths but are 6 inches in diameter. I suppose one could pare them down. Or they could be cut in triangular cross section pieces and glued up into "hex-holes" to make stiffer holes.
>:D
P.S. the shipping is nothing because the holes have no weight!
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I double-tapered the strips so it would form a barreled arrow. Tonkin cane has a higher elastic Modulus or stiffness than any wood, so it should theoretically be possible to make a same-stiffness arrow that is slightly less diameter than a wood arrow. The downside is that it requires precise work in order to get the wall thickness just right. If the strips are too thick the arrow will be too heavy, or have to be made so thin that it is no longer stiff enough. In recent years, I have seen arrows made from some exceptional Douglas fir that is just about as good and a lot easier to make. The hard part is finding these super boards.
Alan
There's lots of old growth Doug Fir around here. Maybe I'll look around an old logging show for some chunks.
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I've made quite a few of these arrows and they are amazing :) Thanks so much for the build-a-long on Paloeplanet Alan.
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There's lots of old growth Doug Fir around here. Maybe I'll look around an old logging show for some chunks.
one quality to consider is a stiffness to density ratio of the wood. it varies quite a bit. not all fine ringed doug fir is the same. something I tried to make sense about in a thread a few threads back.
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I've made quite a few of these arrows and they are amazing :) Thanks so much for the build-a-long on Paloeplanet Alan.
It is good to know you have had success with it. It really takes some commitment to get the most out of making arrows this way.
There is an interesting relationship between the stiffness and density of the arrow material and the properties of the bow. I feel that real sweet spot for split cane arrows is with very heavy bows shooting short arrows. For example and 100#+ horn bow using an overdraw. Even a completely solid-section split Tonkin cane arrow is going to be hard to beat for this application.
I find it most challenging to make split cane arrows for lighter bows that shoot long arrows. For these, there is a very fine line to balance between weight and stiffness of the strips. It only takes a few thousandths of an inch to make the difference between great and failure. For these kinds of bows, it is much easier to make a very good arrow out of more traditional materials like high quality spruce, fir, or some types of pine. Do you agree?
Alan
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It's sounding like it's not worth doing for my bows. I'd still like to try it though. It would give me a leg up if I ever decide to make fishing rods ;) All I have is Moso Boo but I'll keep my eyes open for some Tonkin.
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The moso may work out better for the lighter bows. DC once you have the hang of them you can make the most amazing target arrows too. Alan's idea of gluing alternate coulred pieces at glue-up and putting a twist in them has turned many heads over here :)
Alan you are right my split cane arrows are for 80# bows and up. Eventually I will dig out my flight shooting machine and get back at the distance shooting :0 I've never found any really good softwood over here.....
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Alan's idea of gluing alternate colored pieces at glue-up and putting a twist in them has turned many heads over here :)
I've not seen that unless it was in the build-a-long and i missed it. You wouldn't have a link would you?
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You wouldn't have a link would you?
multicolored and twisted? candycanes?
a pic would be awsome.
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Well, now! A split cane flr rod could be a very worthwhile and profitable endeavor! Way back n the day, you could one for $5-$10 USD. On the other hand, $1.00 an hour was good money! I think the last price I saw on a handmade split cane fly rod was about $150-$200 USD! Sort of raises the cost of fish >:D )F( (lol)!
Hawkdancer
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This threads got me thinking about flight shooting again. :)
There doesn't seem to be much interest in primitive or self bow flight here in the UK and most of the shoots are GNAS (spits on floor as the only class they have that's of interest to me is the ELB) >:(
I might try and organise an informal on at the club where I shoot, but I don't think there would be any serious competion :(
TBF there is some good warbow flight shooting, but I'm a bit on the old side for that now... dunno if I can pull much ov r 80# these days.... (yes I know a good 80# may well beat a 120# with flight arrows )
Sorry rambling now.... good thread this :)
Del
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Well, now! A split cane flr rod could be a very worthwhile and profitable endeavor!
Hawkdancer
I don't know if you intended to write Fir rod but it got me thinking. Has anyone made a "split cane" type arrow out of, pick a wood, and compared it with the same wood in it's natural state. Same diameter etc etc
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I fat fingered that on, should be fly rod! Don't know what happened to that set-up I had!
Hawkdancer
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I thought it was a typo but it sent me in the right direction I think. I cut a bunch of hemlock triangle strips and glued them up. We'll see how stiff it is.
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it got me thinking. Has anyone made a "split cane" type arrow out of, pick a wood, and compared it with the same wood in it's natural state
wayne at trueshafts on haida gwaii bought hexshafts process and thinks regluing makes it stiffer.
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I tried gluing just 1/16"x 3/8" flat lams together once and then made an arrow of it. I don't think I was impressed because I never made any more. But it was a while ago.
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Here's the stuff I used. My plank saw, Made of a grinder and a piece of 1 1/2x3" aluminum channel. The 60° jig made out of scraps from under the bandsaw. My arrow lathe/feather burner made from an old sewing machine. I had to turn an idler pulley to drop the speed. And my prototype glued up old growth Western Hemlock arrow.
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I tried gluing just 1/16"x 3/8" flat lams together once and then made an arrow of it. I don't think I was impressed because I never made any more. But it was a while ago.
I suspect resawing the 6 sections to take best advantage of grain orientation has something to do with increasing stiffness. Nice table saw!
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That's something I never thought of. What direction would you put the grain. Maybe with the growth rings radiating out from the center? If you had primo glue joints that would confuse the troops, edge grain all the way around the arrow ::) ::)
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That's something I never thought of. What direction would you put the grain. Maybe with the growth rings radiating out from the center? If you had primo glue joints that would confuse the troops, edge grain all the way around the arrow ::) ::)
I think so. when you spine a shaft, it is often recommended to put the rings lines up and down, thus you are finding the spine in the stiffest direction. when placing the nock. it's often recommended to orient such that the stiffest direction is against the riser/site window. I think this advice presumes the arrow flexing the most side to side on release on account of the nock flipping off the fingers. and the less stiff side of the arrow hopefully does not come into play.
in a situation like flight shooting, reducing stiffness of the arrow to its practical minimum is done when reducing diameter for aerodynamic advantage, so arrows with less stiff sides might be a disadvantage.
if you placed the stiffer/denser part of the wood growth ring flat on the outer most diameter of an arrow in an annular fashion (with a correspondingly lighter pith towards the center) the physics would be on your side, but you would have to find a board with straight grain ring line for a parallel shaft, or a gentle curving ring line that matched the barrelling desired for a barrelled shaft, and saw each section to follow the early/late ring line.
it could be done, but bamboo might be easier
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That's something I never thought of. What direction would you put the grain. Maybe with the growth rings radiating out from the center? If you had primo glue joints that would confuse the troops, edge grain all the way around the arrow ::) ::)
I think so. when you spine a shaft, it is often recommended to put the rings lines up and down, thus you are finding the spine in the stiffest direction. when placing the nock. it's often recommended to orient such that the stiffest direction is against the riser/site window. I think this advice presumes the arrow flexing the most side to side on release on account of the nock flipping off the fingers. and the less stiff side of the arrow hopefully does not come into play.
I've wondered about this. This is a hard situation to describe and I've read arguments where people were adamant that they were right and the other guy was wrong and it was just their description of what was happening that differed. They were both saying the same thing. I'm going to try ;D I think that the arrow should want to bend away from the bow on release. This can be due to three things. The finger effect that you mentioned but my gut says this is backward. I'll have to look through Tuomos videos to see if I can convince myself. Next is spine oriented so that the arrow wants to bend away from the bow. I'm not even going to try and describe which way the stiff side is facing. And third is one that I've never heard discussed is any slight bend that may be in the arrow. If the arrow is bent that will direct which way the arrow bends, above all else, I think. A good test for arrows would be to have a jig that compresses them lengthwise. See which way they bend from that. Position your cock feather accordingly.
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And third is one that I've never heard discussed is any slight bend that may be in the arrow.
this is called eccentric compression. definitely a factor in engineering calcs. of course all archers shoot straight arrows, no?
I think that the arrow should want to bend away from the bow on release
if you flip the nock end away from the bow with a Mediterranean release, the arrow center is bent towards the bow at the moment the string applies the load? I think the trick is to have the arrow be flexing away from the handle a half cycle later as it clears the bow. shooting off the thumb changes things of course.
spine oriented so that the arrow wants to bend away from the bow.
my guess is with a straight arrow and a mechanical release that imparts little lateral force on the nock at release, spine orientation would become more of a factor. Wouldn't a stiffer arrow vibrate faster, but with less deflection (amplitude)? Maybe Tuomo has some slo-mo of flight arrows somewhere?
A good test for arrows would be to have a jig that compresses them lengthwise. See which way they bend from that.
this is actually a preferred way to spine atlatl darts by many. I have duplicated a native dart of elliptical cross-section. (it was designed to be thrown flatter sides up and down). the dart, like many others, has a somewhat heavy head that makes the dart droop when held in throwing position. my conclusion is that the dart was tuned to the proper spine with respect to a single side, and just about had to flex in the desired direction with any reasonable throw.
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if you flip the nock end away from the bow with a Mediterranean release, the arrow center is bent towards the bow at the moment the string applies the load? I think the trick is to have the arrow be flexing away from the handle a half cycle later as it clears the bow. shooting off the thumb changes things of course.
So the initial flip is in the "wrong" direction and you're depending on the timing of the oscillations for the arrow to clear the bow? What determines the timing? Arrow length? Spine?
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With wood shafts it is going to make next to no difference regardless which way you orientate the grain. On a normal shaft you might get one unit of difference.
divide that difference by 6....:)
I don't think there is any worthwhile gain to go with sectional wood arrows.
The sectional cane arrows are worthwhile because you are using the stiffest part of the bamboo AND they are hollow :)
I'd recommenr making some and see the difference compared to equivalent wood shaft.
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I don't think there is any worthwhile gain to go with sectional wood arrows.
I'll find that out today unless something screws up ;D
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OK glued up strip Hemlock has no advantage over natural Hemlock. Two 3/8" shafts both have 75# spine. The glued one weights 474 and natural weigh 444 so the natural wins but the weight difference may come from different density wood. The glued one may have gotten the weight from the water in the glue so I'll leave them a while and re weigh but I'll not expecting any miracles. I got the same results with a flat laminated arrow I tried a while back. They say laminating makes things stronger but it doesn't seem so with arrows. Like you say Bamboo is a different thing.
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It looks like a lot of activity going on here.
Laminating often improves strength, but has a much lesser effect on stiffness. The measurement of spine is a measurement of stiffness only. Stiffness and strength are two completely different properties.
I have tied other materials in hex laminated arrows with mixed results. The most important property for a flight arrow is one with a very high stiffness or modulus of elasticity. Most bamboo species, such as Moso and the species used for Yumi bows do not have much different stiffness properties than many common hardwoods. Making hex-type arrows out of these types of materials may give you a strong arrow, but not much stiffer than a decent wood arrow. Good Tonkin cane is an exception. It has two to three times the stiffness of Moso bamboo.
Alan
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Thought so :)
DC get some good Tonkin as Alan says it is a different beast.
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I did a quick search and can't find any. At least nobodies bragging about it. I'll phone the place I get my Moso from today.
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I have read that good tonkin is not about a specific species, as much as it is about a place in china where the cane grew stronger.
maybe it is a sub-species? Like not all doug fir is coastal doug fir?
what bamboo do the traditional arrowmakers of east Asia use?
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I have read that good tonkin is not about a specific species, as much as it is about a place in china where the cane grew stronger.
maybe it is a sub-species? Like not all doug fir is coastal doug fir?
what bamboo do the traditional arrowmakers of east Asia use?
Willie,
Tonkin cane is a distinct species (Pseudosasa amabilis) and is native to a very small region in the mountainous area in southeast China. I even have some growing in my back yard, however it struggles if we get any kind of an extended frost.
There are examples of Turkish flight arrows made from split cane also. This kind of flight arrow construction may have become more common if they had access to better material. For the same spine, the split cane Turkish flight arrows are much more bulky and soft.
There are a few species that traditional arrow makers used for self-arrows. Pseudosasa Japonica, or Japanese arrow bamboo is one of the best. I have made split cane arrows from this also. It is much more difficult due to small diameter and thin wall. The biggest pieces are less than an inch in diameter, and it seems more brittle than Tonkin Cane.
Alan
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I have a patch of Psuedosasa Japonica growing in my garden :) It is taking some time and I suspect it isn't particularly happy where it is.