Primitive Archer
Main Discussion Area => Bows => Topic started by: akila on January 19, 2008, 07:33:48 am
-
Hello ...im thinking in making a self bow, that looks like an asiatic bow...do you think its posibile? and iff you think so, where shoud i put the bendings in the bow, to make him look like an asiatic bow???I know that first i should bend the tips( recurve themm), but i dont know in the handle aria how should i proceed....should i try to put some reflex just in the handle aria , so that the bow have that asian look??? thks in advance...
-
Well a really quick way mate is to make a gull winged bow like the scythians, Pre-syahs
Just steam the handle and reflex the heck out of it on a form, and tiller from there it would like great.
-
Well a really quick way mate is to make a gull winged bow like the scythians, Pre-syahs
Just steam the handle and reflex the heck out of it on a form, and tiller from there it would like great.
Yeahhh...i wass thinking on that..and maybe to bend the tips , and try to make themm look like syahs ( a little thicker and narrow as posibile)...you think it would hold together a bow like this..?? im thinking that with so much reflex and recurving tips, maybe the stress will be to high for the limbs....maybe 2 layers of sinew will help?? i would realy love to make a self bow that looks like an asiatic bow.... ::)
-
I'd say use a very strong wood. This style will put lots of stress, both compression and tension, on the wood. That is the reason the Asiatic bows had horn bellies(high compression strength) and sinew backs(high tensile strength). If you use a strong in compression/strong in tension wood and add a bit more length and width you may have favorable results. Pat
-
Chris Cade made a "hornless" horn bow a few years back. It came from a back issue of PA. It had a lot of sinew on the back and had glue on siyahs.I'll dig through my back issues and find it.
-
Hi...and thks guys for replays...i have some ash and honey locust available for this kind of bow..i dont know wich one is the best...honey locust is a little harder thenn ash but i dont know...it will be nice iff you could find that bow made by Chris Cade..thks a lot.I realy like this asian bows, but i dont have acces to materiales, to build one...so i wanna try make a self-bow that looks like an asian bow..
-
Akila, the build-along is in the volume 6 issue 4 magazine. It's called a Turkish Bow without the horn.
-
Akilia, here is a link to a guy who made an Asiatic recurve without using horn, but bamboo instead. It was still built using the same techniques as a horn / wood / sinew bow, so no shortcuts, just another kind of material instead of horn.
http://www.atarn.org/FAQ/bamboo_composite.htm. Atarn in general is a great site for Asiatic bows.
-
Honestly an Asiatic style is defined by the use of horn and sinew. I suppose you are wanting to make a selfbow or sinewed bow that has the basic shape of an Asiatic bow, in other words it has siyahs. That would make it a static tip recurve with the static tips exxagerated over what is conventionally employed. The Asians didn't use horn and sinew for fun, they had to use these materials because wood can't take the compression or tension of the kind of hard bend they used in their bows.
You need to do a few things to be successful. The siyahs are no problem, you just either bend your wood or glue on siyahs like the Asians did. Try and use lightweight materials for siyahs, and make them thin and deep so you minimize mass yet have the stiffness you require. No bending in a siyah. Also, you need to have a low enough bend in your working limbs so you don't damage the wood. This means the working limb is going to have to be long enough and wide enough to handle the bend you are aksing of it. The siyahs are going to make it easy to crank those limbs, they are great levers. So you need to know the limbs won't buckle under the pressure. You can use bamboo backing if you want, that puts relatively more stress on the belly of the limb. It does generate more poundage with less wood though.
Some things to avoid. I wouldn't try making very short working limbs. If you use sinew it would let you make a shorter limb with a harder bend, sinew is great for that. Still, without horn you need to make the working limb longer than an Asiatic bow. You also want to use less reflex than an asiatic bow, you'll be stressing your limbs enough by bending, they don't need to add to the pressure by reflexing the working limb. Wood can only take so much. I would also not tiller like an Asiatic, often they bend hardest right off the handle. This will kill your all-wood limbs. I would spread the bend out over your entire working limb, get as close to the fades as possible. Keep in mind, you have fades off the handle AND off the siyahs. This makes for twice the tricky spots as a conventional longbow. But it can certainly be done, people do make static recurves. So many of the static recurves I've seen, have some set in the limbs that pretty much negatees the reflex of the tips. At that point you've lost what advantage you might have gained from a recurve. But since you are wanting a look (Asiatic), you can live with that.
Basically, you want to make a modest design, longer than an Asiatic and maybe a little wider limbs. Keep the rule of having as much working limb as draw length, so you'll want 28" of working limb for 28" draw. No 48" bows here. 56" for a bend-through the handle bow would be my suggestion, and build the handle area up with leather or something bendy to make it look like the stiff handle of an Asiatic composite. Then add the siyahs to that 56" bow. Might make them around 4-6" instead of the longer siyahs you see on a lot of Asiatics. Try and keep the poundage reasonable. It'll still look like what you want, but it'll be stable. It might always have a bit of kick from the mass of the siyahs. But we're going for looks here.
Good luck, and keep us posted.
-
Hi again..and thks for all your replays....i know that horn and sinew is whatt is all aboute asiatic bows, but here its verry dificult to find those materials to make such a bow....here i cant even find bamboo ,wich is seam to me that you all have there at a verry cheap price...si i realy dont have to much options...i do have a little sinew that i can use and i have find today some bamboo, but its not a single piece of bamboo, its something like 2"wide, 80" long, and aboute half an inchi thick, and it is made from 8 pieces of bamboo glued together.Small striaps of bamboo glued together....and i wass looking a little more closely, and those strips, warr not glue together werry well..i think i can separate those 8 pieces, and my question is.....you think i can use for the belly.. 2 strips of bamboo glued together?? ...i mean, insted of one single piece , to put 2 pieces next to eachothe?...( 1 strip is aboute half an inchi.....so iff i glue 2 pieces next to eachother i could cover the intire belly of the bow)
-
I don't think bamboo has any advantages over other woods as a belly material. It is best used as a backing. I think you could use two strips glued side by side as a backing if that is what you have to work with.
A sinewed bow limb is really going to be your best option. Sinew lets a bow limb bend farther than it could without the sinew. It will allow you to make reasonably short limbs so your poject will have more of the look of a short Asiatic style. Some of the Asiatic bows are longer anyway, often they would be very heavy poundage but you can duplicate them in a lighter weight without the horn.
-
Thks a lot for your help...i wass thinking aboute bamboo for the belly , becose i have seen something similar...an asiatic bow with sinew on the back and bamboo for the belly for better compresion .....i wass surprised my self to see that bamboo wass used for the belly becose i know that bamboo its verry good for backing....i dont realy know how to do the syahs, but maybe i will bend the wood that i already have , and make it like a static recurve...
-
Bamboo can be as strong in compressoin as wood. I just don't see where it is likely to be stronger, unless you have no access to good bow woods. So there is really no reason to add the complexity of the project, when there is no real advantage. some people just do things like that for fun of course, and that is a good reason.
You can splice the siyahs with a v-splice. That is not too difficult. I made an Asiatic composite style bow awhile back, I don't have the pics of the splice as I was doing it but you can see in a couple of these photos hos it was done. The siyah is walnut, and the core is bamboo so you can see the v-splice nicely.
http://s96.photobucket.com/albums/l200/62tomsawyer/Asiatic%20Composite%20Bow/
-
wauuu...nice bow..thks for the pictures....the bow is realy gr8..i love it...can you tell me plz, is there a roule that i have to respect whenn i make the siyah??? do i have to folow the grain or??? i realy dont know how to make those siyah...thks in advance
-
What I did, is to consider what angle the string would be pulling against the wood at full draw. Then I oriented the wood so the string wouldn't be digging in parallel to the grain. I thought this would make it more likely to split, especially given that I was using walnut which is a fairly light wood.
I really don't think it matters too much though.
I would also suggest that you check out ATARN's the Asiatic bow forum. Google ATARN and find the forum, then search it for build-alongs and photos of these bows. I got some inspiration there. Not a whole lot of help, the forum is not real active and they are definitely into making replicas.
-
HI....i know aboute Atarn forum...thats the place where i find themm talking aboute the good properties of bamboo, used for the belly of the bow..they warr saying that its better thenn most woods , for compresion... :-\..can you tell me plzz, how thick should be a siyah???thks a lot..
-
Depends. How long of a bow, what is draw length and how much poundage? I made mine about 8" long and at a modest 30 degree angle. They were about in inch deep, and about 1/2" wide. At the joint I went from 1/2"x1" to 1"x1/2" and cut my v out of that. Then I shaped the front to blend in from the wide/skinny to thin/deep.
-
Hey Tom,
I like that bow in your pics, simple design but looks good. Would you mind giving the deminsions?
Core lenght, width of limbs and pound pull etc
Thanks
Terry B.
-
I should say right off that the bow deteriorated after a lot of shooting, the tiller is off now and needs to be rebalanced. I basically fudged in a few areas and I think it came back to bite me. Also, I initially shot it at 70lb and then worked it down to just over 60lb but this is probably still too much for the design. I was just playing with it though, it was a first attempt.
Going from memory since I'm at work. The bow is 48", limbs are about 1.5" wide. Core is a flattened strip of bamboo (for low mass) that was about 36" long and maybe 1/4" thick (too thick as it turns out). Roughly 8" siyahs and I did a 4" v-splice. I glued horn on the belly and laid a thick layer of sinew on the back, sinew covered the splice and I wrapped sinew around the splice and the handle piece area.
If I did it again, I'd make the core quite a bit thinner. I had to remove a fair amount of the horn to get the weight even down as much as it was. I feel like the limbs were not too short, had they been making 50lb I believe the bow would have been fine. I also should have used longer horn strips so they would cover the belly side of the siyah splice and butt against each other at the handle. Mine didn't and I used wood in those places to reinforce things. I used resorcinol for the horn/core bond, that worked well.
http://groups.msn.com/LenniesBowPage/abcwannabes.msnw?Page=1
-
Tom...i wass looking at your siyahs, and i notest that at the base, where you make the V splice , they are a little bit wider and thicker,,,can you plz. tell me how thick and wide should be a siyah at the base( where i make that V shape)....and btw. ....the bamboo bow is realy nice...so simple and perfect...how did you make it??? did you glue a fiew strips of bamboo together???? or....? today i started to make the bow....i have started to straighten a little a hornbeam stave that i have...it wass a little twist, but nothing sever....ohhh...all most forgot??? how wide shoud be the tip of the bow, so that i can make the V shape for the siyah to glue ..?thks a lot...
-
Thanks Tom.
-
Hello Akila!
I don't know how ash and locust work and perform but I do know about bamboo. I know a lot of people think bamboo is not good in compression and very good in tension, but this is not 100% true. Bamboo is in fact very good in compression also, and I believe it is the closest "wood" comparable to horn. You could say," well ipe is closer because its stronger in compression than bamboo." True, but bamboo is more elastic than ipe and it is lighter than both materials. I think a close second would be yew but I've never worked with yew so I cannot compare. Yes, bamboo takes set, but if it is heat treated well and is good quality it takes considerably less set and holds its shape much better. I have made some "experiment" bows with C shape unstrung profiles and they did not break. Actually, the ones that broke, broke on the back before they broke on the belly and I think its because I didn't use sinew, which is a better backing than wood. Also, Some Korean horn bows were made with bamboo as the belly in place of horn and these bows still had about half-circle reflex in them. So, If you can get a hold of some good bamboo I'd try it out and you just might get a good bow, if not you can always try another as bamboo is considerably cheaper than horn and much more available. Good luck mate! :)
-Alex
-
The other bow is a short bendy handle bamboo-backed osage bow. Single strip of bamboo glued on an osage belly slat.
Alex, I don't deny that bamboo is decent in compression. The widespread use of bamboo flooring boards as belly slats in backed bows, is a testimony to this fact. I have worked with it myself and gotten good results. Good bamboo isn't a lot lighter than several hardwoods. I simply don't think it is any better than other woods, and probably not comparable to the best compression woods like osage or ipe. If you have access to bamboo but not these other woods, then by all means it will make a good belly.
-
Sorry, but I just want to make something clear. When you talk of bamboo do you mean these flooring slates or boards of bamboo as a belly material? If so, this is not what I meant as bamboo for belly, this is actually not good at all to me unless adding lots of reflex since these boards are mostly made from the inner, less dense part of the bamboo and not the wood right under the skin which is very dense. I have made bows with this material and was disappointed with the results until I knew it needed to be made with more reflex to counter the set. What I mean is to use the dense wood under the skin of raw bamboo as the belly, this way it takes very little set when heat treated correctly. The only reason I think bamboo is better than strong compression woods like osage and ipe is because its not as stiff but still has the compressive strength needed in these high stress designs and I think its advantage against horn is that its lighter. Stiff material like ipe just does not work well in these designs, it needs to be like horn, very flexible but also good in compression, thats why I think yew might be a good material as well. Osage might work, but I think because of its stiffness it would become too thin and chrysal unless the bow was made longer to compensate for this, same for ipe.
BTW Lennie, I would pick osage over bamboo every time if you mean using it as a self Asiatic bow,but as just a belly lamination for a short working limb Turk/Korean bow I'd have to go with the boo. This thread is about making it out of one piece of wood though so, I'd have to agree to you. :)
-Alex
-
Alex, I was talking about using raw bamboo as a belly, as I think you were advocating. I just used the flooring material as an example. I'd agree that they have to flatten the boo first, and probably do plane off some of the best performing material that way. It still has decent properties.
I am not that familiar with raw bamboo as a belly material, so I defer to your experience. I was just going by its density which I have some experience with, as well as its structure of having the large bundles of fibers running its length. The fibers do get smaller and more concentrated close to the surface. I just don't see how they contribute to compression properties but they certainly might just by being solid and not having a great deal of pore space. I also agree that bamboo can bend a long way when it is thin, so can some woods. I don't know how elastic bamboo is relative to wood, I thought its utility as a backing came from the fact that it stretches less than wood in that application. When you add a bamboo backing, you put most of the belly wood in compression. Maybe this strength in tension is apart from its elasticity though. Interesting stuff to ponder. I have quite a bit of bamboo, maybe I'll have to give it a try as belly wood. I've admired people's all-bamboo bows made from raw bamboo. You have to get your tapers good though since there is only the opportunity to tiller from trhe sides after glueup.
-
Hi...i have finaly make my decision...and i use a ash board...i already cut the board, and its 66" long, i have cut the V shape( its 4" long), and the piece its 1,2" wide, and 2cm thick.The siyahs i made them 8" long, and i cut the V shape at 30 degrees angle.The siyah are a little bit thicker right now, but i will make themm tinner after i glue themm in place.I dont realy now how much to taper the belly.Right now its 2cm thick the hall length of the wood.I dont want to make a verry heavy bow...25# would be nice...the only problem is that my draw lenght it 29"..so i realy hope that the belly of the bow will not chrisall.I think that i have sinew to put 3 layers on the back of the bow....you think its enugh???/, and do you think that i should have cut the wood a little more wider???...the wood is 1,2" wide , the hall lenght..
-
It will be a pretty long bow, so it won't bend very hard that way which should help protect the belly from chrysalling. And since it won't be bending hard, it will take more wood to make a given weight.
All I can say is, try this one and see how it goes, then use your experience in subsequent attempts.
-
It will be difficult to make such a low draw weight bow efficient with those syhas. They will just be too heavy on a 66" long 25# bow. If I were going to add sinew and syhas I would likley reduce the length to no more than about 56". Steve
-
Hi guys...i wass just comming to say that the bow it seams to me to long right now.. all most 2 meters(80" :o)...so whenn i came to the computer, i just find your replays on me..so your right..its realy to long...o man...and i just work 2 hours to mate the siyahs on the V shape..sanding and all the stuff.. :-\....how long do you think it should be with the siyah and all???
(http://i185.photobucket.com/albums/x212/Akila_07/P1240380.jpg)
Here is the bow with the siyah just fixed a little to the wood( not glue yet)...the siyah will not remain so thick..i will reduce themm later...
-
Looks like you did a pretty good job with the siyahs. You might just make the bow without sinew and see how it performs. Or you could cut it in half, reduce the length and resplice it together in the center with a z- or w-splice. I'm with Badger, something under 60" (including the siyahs) would be better.
-
Has potential as a hockey stick too. :P
-
Has potential as a hockey stick too. :P
;D..this is nice..thks ;)...i realy dont know whatt wass in my head...whatt i wass thinking..aniway i think i would cut one of the ends and make it again...i would not cut him in the middle...im thinking to make him a little bend in the handle...thks a lot for help...i will keep you posted guys..