Primitive Archer
Main Discussion Area => Bows => Topic started by: Ade-The-Blade on March 29, 2012, 07:57:29 pm
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Hi, I'm from the UK, and have just stumbled upon your site. I'm thinking of trying to make a Mongol type bow, but instead of the traditional method of horn/sinew (which I will tackle at a later date), I'm wondering whether or not it would be possible to make one from just wood & bamboo.
I know that the limbs would be under an enormous strain at a full 32 inch draw, and on such a small bow, traditional methods of bow building with wood, would not work. What I am thinking about is making the belly from several veneers of Ipe, and the back of the bow from several veneers of bamboo, and using hide glue to hold it all together. These veneers would be pressed together in a form/mould in much the same way as modern recurve limbs are made. Each veneer would be about 1mm thick. My thinking is that this would enable the bow to bend far enough, without breaking, whilst still retaining power.
Has anybody ever tried doing something like this before, and if so, what were the results?
If not, can anybody suggest any problems that they know of, that I may encounter.
I would like to try this, as an experiment, but if it's been done before, and not worked, I would like to know about it before wasting any time or money on the project.
Thanks in advance for your help, guys.
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Welcome to the forum! Now, since you've "stumbled upon us", you're hooked for life :P
Wood and bamboo simply cannot take the strain as experienced in sinew/horn composite bows. That means the design of the bow will need to be adjusted as to lower the strain on the back and belly, so these materials CAN take the strain. Make the limbs wider, bow longer, lower drawweight...or all of the above.
Just wondering...how many (laminated) bows have you made before?
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Lukasz Nawalny on here has made some bows simillar from hickory and sinew, check out his posts and videos on youtube, Bub
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i think robustus made an all wood and boo, might have been all boo that won BOM last year, Bub
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bubby hit it on the head.....also consider the Mosquito, it out flew all metal planes easily and had not any stress related failures. Laminated wood done correctly will take a great deal of force. ( G force, and bending force )Being from the UK perhaps there are some of the woodworkers from the 30's/40's era who could really enlighten you. I know that Britain's glue was a very guarded secret as well. I would believe your project is doable.
rich
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I would bet that James Parker, "Robustus" has done more research and has a ton of records doing just that with Boo and wood. He has compiled a lot of information on wood tapers to hit specific draw weight with different bow lengths. I own some of his short bamboo backed wood bows and they shoot fast and flat.
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I'm not sure that you can substitute sinew for bamboo and ipe for horn. The values of those materials cannot be matched. (Correct me if I'm wrong). Composite bows store an enormous amount of energy. I heard a story where the string had snapped while trying to brace the bow and whipped around and broke the man's arm.
You can make a bow with lams in the same shape. But its going to be longer and maybe wider. So it wouldn't end up being a short horse bow. It would be like a long 5 curve or something with a much lower draw weight.
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James Parker(Robustus) won BOM in April of 2009 with a bamboo backed and bamboo belly Turkish style bow with ipe/maple lam core and Spanish cedar siyahs. This bow pulls 54"t/t, 60#@30". I've seen and shot this bow. It is an incredable piece of work. 8)
You can read the BOM article in Aug/Sept 2009 , Vol 17 iss. 4 of PA Magazine. It may be in the BOM archives too.
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This sort of question always raises the same answers.
1 - No it isn't possible to directly copy a horn/wood/sinew composite with just wood.
2 - It is possible if you modify the dimensions. If you want it to be short then you need to make the limbs wider and thinner and spread the bending areas along the limbs.
Where in the uk are you? I'm in County Durham
The closely garded secret glue is resourcinol - absolutely amazing glue and i've talked to the guy who developed it. Some of you from over the pond should try it.
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This sort of question always raises the same answers.
1 - No it isn't possible to directly copy a horn/wood/sinew composite with just wood.
2 - It is possible if you modify the dimensions. If you want it to be short then you need to make the limbs wider and thinner and spread the bending areas along the limbs.
Where in the uk are you? I'm in County Durham
The closely garded secret glue is resourcinol - absolutely amazing glue and i've talked to the guy who developed it. Some of you from over the pond should try it.
Hi, I'm from London, so a long way from County Durham. I had already decided upon making the limbs wider and trying for the thinnest limbs that I could get away with, this is why I was thinking about 1mm veneers instead of standard laminations. I was hoping to end up with limbs of 8mm thickness with 7cm width, tapering to approximately 35mm at the point where it joins the Siyahs. My thinking was that the lamination of such thin veneers would allow the bow to flex by the required amount without breaking. I am familiar with resorcinol, but really wanted to try and use all natural materials, so hide glue seemed to be the best prospect.
This is really just meant to be an experimental project, as I like to think "outside of the box". I was thinking of making a small test limb first approximately 18 inches long by 3 inches wide, and seeing if the bending & compression qualities can be achieved first. I'm a great believer in research, planning, design & intensive testing, long before starting an actual project.
In reference to James Parkers bamboo bow, this was what got me thinking about the idea of trying for something new. The fact that he could make a horsebow from natural materials without using horn and sinew, shows what can be done when people think 'outside the box', and apply good engineering design principles.
My intention isn't to just copy a mongol bow, but to come up with something new, using that basic design as a sort of 'starting point', template. The Mongol bow really is an amazing design in itself, but does require the original materials to fully realise its full potential. I am not trying to surpass it, but merely looking at ways to try and produce something close to it, using more readily accessible materials, and using a less labour intensive method of production. The challenge as I see it, would be to do it using only natural materials.
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The Flying Karamozov Brothers used to do this incredible juggling routine in which they would proceed in order thru 5 Disciplines of Juggling, each becoming more complex and difficult. Once they had completed the Disciplines they would then explain that upon mastering your discipline (learned the rules) you were allowed to break the rules. This was called JAZZ! At that point the show became sheer organized chaos as each of the 5 jugglers would begin improvising on the Disciplines.
The same applies to music, engineering, and even relationships. Until you know the limits of known Disciplines any experimentation is likely to be flawed fatally before you start. Like in this case, you have some working knowledge of the bow design, and the limitations of the materials But are your bowmaking skills (your Disciplines) up to the task? If your woodworking skills are up to the task, and your glue-up experience is there, go for it. If not, maybe shelve the idea and work your way up to it.
Either way, I want to see pictures and reports on a regular basis!!! Given your ambition, the bows you build should be very interesting. Welcome to the Forum!
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Limbs 7 cm wide? Wow, that is a lot. But it will certainly lower strain the limbs, which is a good thing for the design you're after. With limbs that wide, you would have to cover the back with several slats of bamboo. Probably three slats, because with two slats, you will not end up with a nice backing near the tips, where the limbs are much narrower. Preparing multiples bamboo slats for glueing them down, won't be easy, I guess.
The number (and thickness) of laminations does not determine how far a bow will bend. It's not as simple as "the more lams, the less likely it is to break". Thinner lams are easier to bend, and will keep their shape better once the glue has dried. But it has drawbacks, as prepping the lams is a lot more difficult, and fitting all lams together before the glue starts to set, might take a lot of effort. I would advice you to use several lams of 3 mm thickness. That's thin enough to create sharp curves in a bow, yet requires only a few lams. Requires less glue as well. Furthermore, clamping lams of 7 cm wide will be a real challenge. How will you be clamping the whole set? A form and airhose? Or.....?
Just wondering. What is your bowyery and laminating experience? Have you made any bows before? A laminated composite bow with nice glued in recurves is a really advanced project. Ambition is great, but don't get ahead of yourself.
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Until you know the limits of known Disciplines any experimentation is likely to be flawed fatally before you start.
Either way, I want to see pictures and reports on a regular basis!!! Given your ambition, the bows you build should be very interesting. Welcome to the Forum!
Hi,
I agree with you wholeheartedly. Part of the reason for this particular experimentation, is to find out just how far those limits really are.
My woodworking and gluing/laminating skills are quite well honed (in terms of skilled joinery), but i'm not experienced in bow-making. I've studied up on the subject(over the past few years), and made test pieces to test out pliability, energy storage & breaking forces (I've made enough test pieces to make a dozen bows & learnt a lot from the process), but making a straight-forward bow does not excite me as much as tackling a more complex task.
I'm already aware of the difficulties of the task, and the likelihood of getting it wrong, but the aim of this exercise is to learn through experimentation, not necessarily to end up with a working bow. If I do succeed, then it is a bonus, but not necessarily the goal. It is the experimentation that holds the fascination for me.
Whether or not I actually make a bow of this design is entirely dependent upon the results of the testing phases. I've made simple working test limb sections from thicker laminates (tapered & non-tapered),which would be fine for regular longbow use, but for the extreme bending forces that a Mongol bow requires, these would not even be close to suitable.
If testing proves to be successful enough, then the actual bow project will be undertaken. If after exhaustive testing I still cannot attain the required results, then any lessons learnt can always be applied to a less ambitious project.
Sometimes the journey is more interesting than the destination.
Thanks for all the input & advice so far, I welcome as much input as possible as it is food for thought.
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With limbs that wide, you would have to cover the back with several slats of bamboo. Probably three slats, because with two slats, you will not end up with a nice backing near the tips, where the limbs are much narrower. Preparing multiples bamboo slats for glueing them down, won't be easy, I guess.
The number (and thickness) of laminations does not determine how far a bow will bend. It's not as simple as "the more lams, the less likely it is to break". Thinner lams are easier to bend, and will keep their shape better once the glue has dried. But it has drawbacks, as prepping the lams is a lot more difficult, and fitting all lams together before the glue starts to set, might take a lot of effort. I would advice you to use several lams of 3 mm thickness. That's thin enough to create sharp curves in a bow, yet requires only a few lams. Requires less glue as well. Furthermore, clamping lams of 7 cm wide will be a real challenge. How will you be clamping the whole set? A form and airhose? Or.....?
The method I was intending for the bamboo, was to stagger the laminations (Imagine a cross section as looking like brickwork), with 3 on the top face, as you suggest.
I have a design in mind, for a temperature controlled trough, so that all the laminations can soak in the glue, and then be put straight into the form in one go. The trough & form would be specially made for the task (i've already worked out the designs).
I'll try the 3mm laminations, as it seems like a good idea.
As I've stated in another post, I've done a lot of testing, and have a lot more testing to do before making the final decision as to whether the project actually goes ahead. I tend to do loads of research & testing, as this approach has always worked in the past for just about everything I do.
Thanks for the input.
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Contact James. He is a very open guy that shares info. James does lots of research and expermentation with each of his bows and has always been generous sharing info with me.
James is Huntwortyproductions
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I say go for it. I have no advice to offer about if it would or wouldn't work....
Here are a couple of cool quotes from Thomas Edison....
Here is what he said when someone told him he had failed 10,000 times at making a light bulb.
“I have not failed. I've just found 10,000 ways that won't work.”
Can you imagine breaking 10,000 bows before you made one that worked? That would be quite an education....ouch.
Lately I feel like eveything I touch breaks but I'm learning and that is a step in the right direction.
You are standing on the edge man....You are thinking and thinking and thinking and researching....
Not that it's a bad thing at all. I did quite a bit of reading and so on before I started and now I sometimes think I should do more planning but
I get impatient and start then learn along the way.
At some point you just need to jump in and start....
Here's another quote from good ole Tom.
“If we all did the things we are capable of, we would astound ourselves.”
I think once you have achieved your goal you won't be the only one who is astounded. It will be AWESOME!
make sure to post your results so we can check it out. Good luck!
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I understand where you are coming from regarding making this bow.
It sounds like you've done enough testing and are maybe over-complicating things.
KISS is a good acronim!
If you are going to make 'mini' limbs to test things they must be scaled in every dimension.
Bow making is all about the ratio of width to thickness of the limbs - this is what determines how far a limb will bend before taking excessive set.
Make your limbs wide and thin enough and it certainly is possible to make a limb that will bend in a tight enough radius to look from the side , at least , like a mongol bow in the way that it bends.
The problem with making wide and thin limbs is that they carry a lot more weight than narrow and deep limb's do for the same stiffness. The beauty of hornbows is that you can make the limbs very narrow/deep compared to wood and hence get a faster return. Take a paper thin wood shaving and look at how flexible it is. It will bend in a full 360 degrees without damage but bend it that far and then release one end and it will return slowly.
Personally I say forget the tests for now, take what you've learnt from them and get the first proto-type built - it will teach you what you need to know.
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it is possible to make such bows.. Ive been working in that area for several years now,,, to start ,, you will have many failures,,,many,,, i have tried any and all applications of bamboo for backing and belly,,, a vertical stack glued for the back is just not worth the time involved making such a strip for a backing,,their are limits to any and all natural materials in bow making,,, all can be pushed to their apex,, first the rules have to be learned before the can be bent,,, all the years i have been making bows it has truly been fun but at the same time its been frustrating and very costly.. my advice ,, no matter what you try or build- write it down , keep immaculate records on every bow you attempt to build,, this way you wont duplicate so many mistakes and your successes will also be written down ,so as to replicate those bows...
start by building light weight bows and move into heavier # after all the bugs are worked out through your designs.. this will save vast amounts of time and materials= ( money)... have fun building your bows,thats when you will build your best bows....good luck in your endeavors
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Thanks for that info, I've recently (in the past few days), modified my design to make it a take down version of my original design. This will enable me to try out different limb designs without having to make a complete bow each time.
I've enclosed an attachment of the basic design. This is not totally to scale, and is really just for my own personal reference. All the fine details and manufacturing processes are already worked out, in my head.
I'm currently waiting for delivery of materials (Ipe & Bamboo), and have already started making the form to press the limbs. I will use Cascamite for the first bow, just to get the project off the ground, as it will save me time and money making the special trough for the hide glue. If all goes well, then I'll replicate using hide glue.
The intention is to have a low poundage bow (approx. 30lb@28), as it will be shot using thumb release.
My Siyah is designed to have maximum leverage upon the limb, whilst allowing more flex in the entire limb. The Siyah itself will be made from vertical laminations of hardwoods laid in different grain orientations. A dowel of horn will be pressed & drilled and the string slot will be cut into it.
I have a few contingency plans in mind, depending on the exact nature of any limb failure. The only foreseeable problem will be with getting the limbs to bend far enough without breaking. I can't anticipate any Siyah, or Riser problems. If the bamboo fails, then I may make a second set of limbs with a flax backing on top of the bamboo. If the Ipe fails, any potential solution will depend on the exact nature of the failure. I will cross that bridge when I come to it.
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The simplest and perhaps best syhias are to be got from a naturally curved branch. There are hundreds in any patch of woodland! Ash is good because it's easy to split. Cut a piece big enough to be split down the middle so no pith is near where the shyias are sitting in the wood. If the curve needs to be altered then steam and tweak the shape on a form, do both on the same form. This way the grain isn't cut throught anywhere. Pieces like this can also be quick dried in not much longer than it would take to laminate and allow glue to dry. They should be v-spliced into the main limb before the backing is applied. Make your splices 1 inch wide and 4 inches long. Bamboo applied over the finished splice.
If I were you I would reduce the reflex out of the handle.
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There seems to be a tendency to grossly overthink the wooden horsebow and doubt the ability of good woods to stand up to all but the most highly stressed of these designs.
Pick a design that is known for being longer with less sharply angled siyahs.
Quite a few of them were known for being 60 inches long with siyahs at only 30-35 degrees.
People on here make recurves of shortish length and full draw capability all the time.
There seems to be a misconception that labelling a bow a "horsebow" instead of just a short recurve somehow stresses the whole bow much more.
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Thanks for those replies. I've skewed the image in photoshop to produce a less reflexed handle & slightly altered Siyah angle, as well as longer limb length. Looking at the new image, it seems to be a bit better(less stress on the limbs), so I think I will make the bow to suit this new profile.
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Don't be so easily influenced by those glass caricatures that you're drawing your diagrams from. ;)
Most of the grave evidence shows a more sweeping backward curve from the handle transitioning to the limbs rather than a severe setback. There ARE varieties that have severe setback but you should be choosing the less severe ones to model the bow after.
Your siyah joining technique is a very poor one and will add far more mass than a v-cplice and lower angle.
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There is a bamboo horsebow for sale over on the Korean Traditional Archery forum, there are also links to articles on it's construction.
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I like horsebows , few my bows - selfbows , wood/sinew and horn/wood/sinew http://www.fotosik.pl/u/robbin/zdjecie/1/album/1150269 .
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There is going to be a high likelihood of the limb breaking right where your riser ends. For a horse bow design that is where a ton of strain is happening and it seems much too abrupt of a change from riser to limbs like PatM mentioned.
I own one of James' Bamboo Turks and its an amazing bow that I just shake my head at when ever I pick it up. Light as a feather and shoots real nice.
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Hi Everyone,
It's been a while since I posted, due to many different things going on in my life. I started the bow in April, but I have to do all the work outdoors, and April has been virtually non-stop rain for the whole month, so there have been a lot of delays. This month, I've been managing to do a little here and there, as time permits.
I've almost finished the first limb. It has a tapered belly of Ipe (1mm at mid-limb and 3mm at riser end, a 2.5mm mid core of mahogany, a 3mm outer core of bamboo, and a 1.5mm backing of rawhide. I will be adding a bit more Ipe at the limb butt, to produce a "tower effect", for re-inforcement purposes.
I have pulled it to an approx. of 26-28 inch draw quite comfortably (19lbs), and it will still pull more. I will shave down the section marked by the red arrows to allow it to bend a bit more. I have also left it approx. 1-2 inches longer than I originally intended, so that I can try for a 30-32 inch draw.
The Siyah was not glued on in the picture, the only thing holding it in place was it's leverage design. When the entire bow is made, I will glue them on temporarily with hot melt, and bind them with linen so that I can test the bow for poundage and draw-length. If the limbs take the strain easily (with plenty to spare), and I decide that I want a higher poundage, then I can cut the limbs down and glue the Siyahs permanently with Cascamite.
So far everything is working out fine, and I've learnt a lot throughout the whole process. :D
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I've not had great experience with Ipe if it gets to thin. Maybe grain needs to be perfect for it to work but I've had lifts which don't happen when the Ipe is thicker and under less strain.
Bamboo backed with sinew was used in the far east as a more common and less costly alternative to horn/sinew. I've been thinking that with a little compromise in length and limb width a decent bamboo backed bamboo horsebow would be possible.
Will be an interesting thread to follow.
Mark in England
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If you're only making a prop horsebow just steam a piece of elm or rattan into an appealing shape.
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Now wasn’t there an article in Primitive Archer magazine , some time ago, about a gentleman who built a horse bow from wood , and made it work by pre bending 4” of reflex into the mid limbs ...??? Maybe about 15 years ago ... ???
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This is the limb shape at rest. I steamed and pressed the individual laminations into shape first, then a couple of days later glued them up and placed them in the same form/press. This one limb on it's own will pull to 19lbs (with more in reserve). I am going to make a holding jig to enable me to clamp the limb to the bench more or less vertically, with a 5-10 degree forward tilt, to simulate the intended handle reflex, and then do another test. The final draw length & poundage will depend on whether I use a 5 degree handle reflex or a 10 degree one. As long as the finished bow comes up between 30-40lbs, and can make a 28 inch draw, I'll be happy.