Primitive Archer
Main Discussion Area => Horn Bows => Topic started by: Tom Dulaney on May 23, 2017, 06:51:53 am
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Some Turkish bows look like they have really, really short limbs.
Do you think it could be possible to make a pseudo-Turkish bow out of a 76cm (30 inches) stave?
I only have Juniper, no bamboo.
I understand that bows become more efficient as the limbs get shorter relative to the weight and length of the siyahs, but I want to know the limits.
And I just want to make it clear: I know I can't really make a true Turkish bow, as I don't know much about them.
I am only asking you guys because you make the shortest bows.
I also do not intend to make a bow with extreme reflex like a Turkish bow.
I just want to turn a really short stave in to a moderately reflexed bow, by adding siyahs and sinew, and possibly horn.
This thread's title was basically an attention grabber.
Thanks!
TD
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You need to read the Karpowicz book. There is a tremendous amount of information involved. So much work goes into it, your wood core matters greatly and from what I understand the wood must be ideal.
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Magyar bows have limbs only about 12inches long. Their dimensions seem to be 12" each for limbs and handle with 10" sijahs.
Two 12" limbs and a 6" handle would probably be ok.
This book: http://www.academia.edu/11151943/The_Hungarian_Bow_of_9-11th_centuries_-_recommendation_for_bow_constructions_2011_
I found invaluable as it gives a full list of measures.
Having said that, the karpowicz book is essential reading, though I do find it confusing at times.
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Also, you really need to check out Kamil's work here :http://www.primitivearcher.com/smf/index.php/topic,40574.105.html
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stuckinthemud....I'm sure you've read what Adam says about density and shearing factors for a core?Without as much reflex I suppose it could work ok.
Anybody understand about the statement in Adams book about the exponential decrease of the core he mentions?I've made a lot of self bows and quite a few sinewed bows with extreme reflex but still wondering about that statement.Guess I just gotta dive in a see what happens???
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Yes, but if he's only going for moderate draw length then it might work, and the experiment could be fun. Equally, I would expect performance to be not wonderful, especially with long heavy sijahs denting performance but that doesn't mean he won't get a bow out of it. I put forward the Magyar rather than the Turkish as the limbs are the right length and nice and wide, wider than Turkish types so better chance of success as he will need wide thin limbs for this, I would think.
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Yes I agree,and thanks for the link.Very interesting.
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Yes, but if he's only going for moderate draw length then it might work, and the experiment could be fun. Equally, I would expect performance to be not wonderful, especially with long heavy sijahs denting performance but that doesn't mean he won't get a bow out of it. I put forward the Magyar rather than the Turkish as the limbs are the right length and nice and wide, wider than Turkish types so better chance of success as he will need wide thin limbs for this, I would think.
Thank you for you contributions, you've been very helpful. I have wide flat limbs with good growth rings so I will try my best to emulate the Magyar bows, I love short bows.
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You need to read the Karpowicz book. There is a tremendous amount of information involved. So much work goes into it, your wood core matters greatly and from what I understand the wood must be ideal.
Thanks and I believe I have the ideal wood here. The growth rings do not arc sharply, the wood is knotless, naturally flat back so I have a rectangular cross section, etc. Wood was taken from large diameter juniper limb, which was soaking fresh green wood not at all dry or brittle. Since the limbs are so short I may even go all out and make some horn bellies (i have always been intimidated by the idea of making a long horn belly, for my first horn bow).
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Good luck and keep us posted, I'd love to see how it all works out.
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mikekeswick on here made a Turkish bow about 24" long. There's no real limits to bow length for all intents and purposes.
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Interesting project keep us posted & thanks stuckinthemud for the link on the magyar really like that bow !
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Yes Mike's little bow drew 14" if I recall.24" long overall.Limbs of rattan????Barely 1" wide limbs.Drew 40#'s then.Rests with 5.5" reflex.
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I think it was actually material correct.
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Yes I should of explained.It was a sinewed horn bellied rattan core bow.
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I should have explained that I thought it was ALL material correct and used a wood core. Have to check.
http://paleoplanet69529.yuku.com/topic/48852/mini-hornbow#.WSTUxYWcHIU
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http://www.primitivearcher.com/smf/index.php/topic,59379.0.html
Correction a Rowan core.
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Ah, He made TWO of them.
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Yes.Old Mike has turned into a referral point nowadays.Quite the talented bowyer.
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So, you are thinking of doing a one piece core...handle and laths from the cedar limb stave, I'm understanding?
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A Magyar is a better solution for your stave. Aim for something like 120cm ntn, 150° reflex in the grip with a smooth and large radius. You can use bone plates for the scarfjoint in the grip. The ears around +24cm from apex to the nock, limb to ear angle 140°. Don't use horn plates for the ears, they look silly and don't add alot stiffness, all they do is add more weight and create more trouble.
The ears can either be V-spliced or you can use a scarf joint. If you use a scarf joint, sideplates might be necessary. Antler is the best material for that, but it can be hard to find good pieces. Bone from horse ribs is possible too, but it's pretty messy to process the stuff. If you use plates, note that those were around 0.3mm thick on the originals. The cross-section of the ears was triangular.
Plates add quite alot of weight and it can be a pain to glue on, so if you don't make a heavy bow, it's not worth the trouble. Better make a short V-splice and triangular cross-section ears.
As recommended for a beginner, use even thickness for horn and wood in the limb, 4.5-5mm will be good at that lenght. Expect around 70-80g sinew for a 50-70# bow. You can add 10g on top of that if you feel insecure, for the wrapping of grip and end of the horn you don't need much.
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I have been thinking about this thread this week while I was on the road and wondering why the Magyar would be a better choice over the ottoman style bow of equal reflex , maybe there is some thing I'm missing , would it be performance or stress on the bow or ease of build ?
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The rationale behind recommending the Magyar is purely ease of construction: how many laths you could get out of your stave?
If you can get out 2 with thickness of at least 1.5-1.8cm, you can make a 3 piece ottoman, with each lath 70cm comfortably for a 120cm ntn bow. You still need third a piece for the grip splice. Three piece is a bit harder to bend, because the Tip/kasan radius is quite tight and stuff breaks quite frequently if it's not green.
If you can get out 2 laths of lesser thickness, like 1.2cm, you can make a 5 piece ottoman, but like above you need a grip piece to splice and more material for the tips. I prefer to laminate 2 thinner pieces of wood for the tips, those tend to survive the tight radius more frequently.
If it's none of the above, you can make a Magyar.
You will need to make a number of bows before you may wonder about peak performance, first considerations are to keep it simple, stable and to save weight in the ears.
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Ok thanks this is not my thread but glad you joined us over here it's nice to have experienced hands on guys here I'm in the process of gearing up for my first composite I'm fortunate enough to have plenty of materials to go what ever direction needed but thanks so much for chiming in it's appreciated !
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Good luck with your projects!
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Hear is some interesting handle designs for the Magyar bow & siyas I have seen around the net 3 peace Magyars done with similar to C with steamed bent single peace core & 130 Deg angle , also have seen 2 peace laminated siyas made out of strait grained wood vs crotch wood every thing about this design seems would be a little simpler then the Turk bow
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Handles
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Siyas
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130° in the grip or in the ear are too much. Both will make the bow unstable and call for problem fixing that shouldn't be there in the first place. The acute angle in the grip will also make it stack earlier in the draw.
Peter Bencsik recommended 150° in the grip to me.
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Seems the magyar might need to be sinew wrapped in handle and siyah.The turk version not.
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Seems the magyar might need to be sinew wrapped in handle and siyah.The turk version not.
I saw that some guys have wrapped the handle and siyahs transition on the turk and crimea-tartar bows too ... Maybe this is done only on heavy ones or after some delaminations ocurred ?
Some old mongol bows from13th century found in desert had cross wrappings on whole limb...
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Yes correct I believe it was done on some of the heavier Turk bows too.Guess that could be a determining factor on any style horn bow really.
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Old Tom started a interesting topic & disappeared..Ha ! but I'm learning a lot ,Bjoern thanks for the clarification on the limb angle ,with these Magyar it seems wrapping is more comon practice with the scarf joints there doesent seem to be as much artifactual evidence with that style as the Turk bows (3 &5 peace )so some is guess work ,but I have seen them made on other sights with the handle made like a Turk bow with the exception of the limb angle non wrapped I'm just wondering what kind of draw length you could exspect out of Toms bow with Bjoerns recommendation 47-48 in. Ntn. ? I'm curious also if this style bow could be field strung with a primitive stringer as opposed to a bracing board ?
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You can approximate the drawlenght of a turk by dividing half the lenght NtN, taking limb lenght (excluding the grip) to the nock * 1.5
E.g. for the standard 108cm ntn turk, that is 54cm minus 5cm grip = 49cm.
So 49 * 1.5 = 73.5cm theoretical maximum drawlenght. Original war arrows were around 71cm long.
Modern bowyers sometimes like to wrap the Kasan Eye for safety when the bow is untwisted with heat - the sinew is removed after the corrections. Especially bows with matching grooves have problems there.
Another reason for wrapping the transition of working limb to ear is, that Magyar and Cagaan Chad type bows have the horn end right there. Without wrapping, the horn always needs to continue a couple of cm into a non-flexing part, lest it delaminates eventually. On the positive side, those bows can be built with relatively short horns!
Don't know if somebody calculated the ratio for Magyar bows or other types with non-flexible kasan eyes. The flexibility in that section adds a couple of centimeters more drawlenght. It should be something over 30" for those with rigid ears in a 120cm ntn bow.
About stringing them, bows with reflex in the grip are a bit harder to string. The large and rigid ears make them a bit unwieldy if you're a small person. It's better to have either a pegboard or a helper to string them, so everything is completely under controll. Never string a hornbow on the first time without Tepeliks!
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Good morning Bjorean at least its morning here 3:30 am thanks for the info thats impresive draw for short working limbs like those, I have a 29 in. Draw thats why I was asking with Toms bow as a comparison , the reason I was asking about the stringing I mostly use my bows for hunting & in my state while hunting state propertys you must unstring your bow to and from your hunting area ! All though I think they except locked cases , the interesting thing about the Maygar is you could make those bows with limited material shorter horn etc. Great thread here thanks !