Primitive Archer
Main Discussion Area => Bows => Topic started by: Badger on February 28, 2018, 08:22:33 am
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I say common sense even though it might take some of us including me a decade or more to figure it out on our own. Somethings only make common sense once you realize it. Somethings I consider logic and common sense may or not be 100% correct. I wanted to start a thread that should be helpful to any bowyer new or experienced that we can use on the bow bench when building a bow. I have to admit that I have learned more while helping others learn because I was forced to explain something that I had been doing by habit for many years. More often than not when I started to break it down so I could better explain it I would find a small hole in my logic and something new would be revealed to me.
I doubt we will come up with more than about 10 items. Feel free to challenge and debate, I promise to stay open minded. The goal is to come up with several little jewels that can be passed along within our community. Logic and common sense are things that could apply to any weight bow of any style or length. I suspect a lot of it will be a just finding a better more understandable way of saying something.
You go first!
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The first piece of advice I hand out is always the same, think three steps ahead at all times. Always consider how what you are doing now will affect the build later on.
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Yea Pearl that's a good one. I think the way I address that is mainly roughing everything out a bit oversize until I find out how the wood is behaving. Nothing worse that going from floor tiller to brace or the tree and finding out one part of the limb is already bending to its limit, now the whole tiller shape has to be built around that one section of limb.
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The best advice I was given when I first started making bows was, "don't over think it, we're just trying to make a piece of wood bend evenly."
That piece of advice made me really slow down, which is what I needed to do more than anything back then.
Tattoo Dave
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For beginners: Start slow and learn the basics of tillering. I don't know how many times I've seen a beginner on here want to make a complicated bow like a horn composite for their first attempt.
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The memo some seem to overlook as hinted to by badger.Make it wide enough and long enough to begin with until you get to know the woods characteristics.Basically that has a lot to do with density.
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Draw the bow on the tillering tree as close as possible to how it will be drawn by hand. Balance limb strengths relative to that. That seems like common sense/logic.
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something that took me a bit to realize at first was "build a bow to the wood's specific limits and characteristics". For some reason, I used to think that if you tillered good enough you could make a bow from most any wood and design. When the truth is some designs are downright impractical if not impossible for some woods. Material choice is one of the most important aspects of bow building. I'm not saying every bow has to be Osage or yew, but just don't expect the radical designs you see with Osage to work on a red oak board bow, I learned that the hard way. I don't know why I thought this way at first, maybe because of my fascination with making great things out of mediocre stuff, maybe even what other people consider junk (you know the "one man's trash is another man's treasure" deal). I also think it might have been because I didn't want to buy bow wood, especially when the good stuff can be quite pricey.
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++++++++++++1 gfugal
I disagree with the "start slow" school. I say start with decent but inexpensive wood and charge ahead. We learn faster from mistakes than from success. We also learn SKILLS faster from repetition than from contemplation.
When we fail, we should recognize the reason, if possible, and try again.
Remember the adage, "If at first you don't succeed, try, try again?" It's worth more than the idea that you MUST succeed the first time. My first attempt was nearly done and looking good when it exploded. I realized that I had used a stick that had a bug problem. I learned something about choosing a stave....
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I agree with starting off with easier basic designs until we get the tillering aspect and understanding of wood down a little bit.
One of my favorites, thickness controls how far it can bend and width controls how far it will bend.
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Perhaps the KISS principle, along with the planning/considering 3 steps ahead as to what you are doing, leave a margin for error, and remember: Murphy's Law is governed by Mc Connell's Therom, I.e. Murphy is an optimist! Watch what you are doing, look carefully, listen to the "old guys" and use their knowledge! And don't be afraid to ask questions - the only dumb question is the one you don't ask! And learn how to post pictures! >:D (-P. I'm still learning this craft!
Hawkdancer
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One of my favorites, thickness controls how far it can bend and width controls how far it will bend.
Quite honestly I never understood that quote. Can vs Will is what? Can implies theoretical, will is a future tense of what is going to happen. I think they are too similar. I offer my own take on it for debate. I think it makes more sense this way "thickness controls how far it can/will bend, and width determines how strong it is at that bend" (i.e. width determines the poundage of your bow). Hypothetically let's imagine two bows of the same thickness but one is twice as wide. I think both can bend theoretically similar draw lengths as the fibers are stressed the same, since they are just as far from the neutral plane as the other bow. The only difference is the wider bow has many more fibers stressed, thus it has a higher poundage. Think of it as adding more workers hoising something up, not by adding the extra workers to the same rope (that may cause the rope to break) but by adding another rope alongside the first rope and its workers.
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Let the stave determine the design. Jawge
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One of my favorites, thickness controls how far it can bend and width controls how far it will bend.
Quite honestly I never understood that quote. Can vs Will is what? Can implies theoretical, will is a future tense of what is going to happen. I think they are too similar. I offer my own take on it for debate. I think it makes more sense this way "thickness controls how far it can/will bend, and width determines how strong it is at that bend" (i.e. width determines the poundage of your bow). Hypothetically let's imagine two bows of the same thickness but one is twice as wide. I think both can bend theoretically similar draw lengths as the fibers are stressed the same, since they are just as far from the neutral plane as the other bow. The only difference is the wider bow has many more fibers stressed, thus it has a higher poundage. Think of it as adding more workers hoising something up, not by adding the extra workers to the same rope (that may cause the rope to break) but by adding another rope alongside the first rope and its workers.
If you read it carefully it is worded just as it should be worded. If it is confusing you need to keep thinking about it until it is no longer confusing because it is one of the most basic and important fundamentals of bow making. For any given thickness there is only one minimum radius that the limb can bend to at that particular spot without damaging the wood. Any time a bow takes set in a particular place it is because the width was too narrow for the particular thickness or the thickness. Once this concept is understould it will always drive your designs. If a bow has paralell limbs and even thickness it will bend next to the handle and the wood will be more stressed there. If you start tapering the sides of the limbs it will start to bend more ( Pyramid) and your even thickness will be right. If you choose to leave the limbs parallel then you will have to start tapering the thickness so that the limbs bend more as they go away from the handle, this will even out the stress on the wood.
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stay calm dont rush....never rush, it always goes wrong..be patient..
measure three times and you'll get it right when you cut
best advice I know
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If you read it carefully it is worded just as it should be worded. If it is confusing you need to keep thinking about it until it is no longer confusing because it is one of the most basic and important fundamentals of bow making. For any given thickness there is only one minimum radius that the limb can bend to at that particular spot without damaging the wood. Any time a bow takes set in a particular place it is because the width was too narrow for the particular thickness or the thickness. Once this concept is understood it will always drive your designs. If a bow has parallel limbs and even thickness it will bend next to the handle and the wood will be more stressed there. If you start tapering the sides of the limbs it will start to bend more ( Pyramid) and your even thickness will be right. If you choose to leave the limbs parallel then you will have to start tapering the thickness so that the limbs bend more as they go away from the handle, this will even out the stress on the wood.
I get the relationship, it is definitely more confusing than what I was making out to be, but that doesn't change the fact that that quote is hard to understand. What determines whether a wood fiber is damaged is the stress it undergoes. This is solely related to the thickness (where that fiber is in relation to the neutral plane) and the bend radius. Width has nothing to do with whether that fiber gets set. It may do so indirectly because if it's wider it takes more energy to get those multiple fibers to bend that same radius, therefore by it resisting bending they don't bend as far and thus don't get stressed as much (hence how you can tiller by adjusting the width in pyramid bows and such). However, if you took two flat pieces of wood of uniform thickness and width but one is just twice as wide (this is to eliminate different resistances to bending that cause tiller. Imagine the bend test Tim baker does). If you bent both pieces of wood the same radius theoretically all fibers would be under the same stress whether they are in the narrow piece of wood or the wider piece of wood. If the narrow pice gets 1/2 inch of set so would the wider piece (as long as they are the same wood, with not varying defects). The only difference would be that the wider one would take much more force to get it to bend to that same radius.
So yes I understand the width will determine tiller too, but that's not because it makes it so the fibers can stand more bend, just that they require more force to get that same bend. Thus by manipulating the width, you manipulate the forces required to bend the wood and thus get the tiller you desire. Same can be done with thickness but that's another relationship entirely.
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If you have control of your bow it will be just as stated, if you don't have control all that will go right out the window.
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gfugal, I hear you, that saying confused me for a long time too, still does sometimes. At the very real risk of making it more confusing for somebody, I'll offer my current take on it.
If more words were used to make it more specific (albeit less pithy), I think the saying would be:
Thickness determines the minimum radius to which the wood can be bent without taking set or breaking; for a given thickness, width determines how far the wood will bend when subjected to a given draw force on the string.
If I have a segment of limb of a certain thickness, I can bend that segment to a very specific minimum bend radius without damaging the wood.
If I have a segment of limb of a given width, it will bend when the string is pulled. If I make that same limb segment narrower and pull on the string with the same force, the limb will bend farther.
The practical implications being, among others: for a given bow length and draw length, the best bow is one that is everywhere thinned only as much as it needs to be to allow the necessary bend, while also being only as wide as it needs to be to achieve the desired draw weight. Which of course is the basis of the mass principle, etc. etc.
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If you have control of your bow it will be just as stated, if you don't have control all that will go right out the window.
I think we are saying the same thing. In my above example of two identical uniform pieces of wood, if you place a 5 lb weight on the end, the narrower one will bend more than the wider one. So you say "thickness controls how far it can bend and width controls how far it will bend" I think I get what you're saying now. Thickness determines how far it can bend safely without getting set, damaged, or breaking. Width, however, determines how far it will bend under a certain force. A wider bow will bend less than a narrower bow. This is essentially the same thing I was saying that thickness controls how far it can bend, and width determines how strong it is at that bend. The reason I think the original quote is confusing is because it makes it sound like width affects the ability of the wood bend further the smae way thickness does, when that's not the case.
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If you have control of your bow it will be just as stated, if you don't have control all that will go right out the window.
I think we are saying the same thing. In my above example of two identical uniform pieces of wood, if you place a 5 lb weight on the end, the thinner one will bend more than the thicker one. So you say "thickness controls how far it can bend and width controls how far it will bend" I think I get what you're saying now. Thickness determines how far it can bend safely without getting set, damaged, or breaking. Width, however, determines how far it will bend under a certain force. A wider bow will bend less than a narrower bow. This is essentially the same thing I was saying that thickness controls how far it can bend, and width determines how strong it is at that bend. The reason I think the original quote is confusing is because it makes it sound like width affects the ability of the wood bend further the smae way thickness does, when that's not the case.
I like to leave it a little vague on purpose, it forces us to take a little closer look at it.
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gfugal, I hear you, that saying confused me for a long time too, still does sometimes. At the very real risk of making it more confusing for somebody, I'll offer my current take on it.
If more words were used to make it more specific (albeit less pithy), I think the saying would be:
Thickness determines the minimum radius to which the wood can be bent without taking set or breaking; for a given thickness, width determines how far the wood will bend when subjected to a given draw force on the string.
If I have a segment of limb of a certain thickness, I can bend that segment to a very specific minimum bend radius without damaging the wood.
If I have a segment of limb of a given width, it will bend when the string is pulled. If I make that same limb segment narrower and pull on the string with the same force, the limb will bend farther.
The practical implications being, among others: for a given bow length and draw length, the best bow is one that is everywhere thinned only as much as it needs to be to allow the necessary bend, while also being only as wide as it needs to be to achieve the desired draw weight. Which of course is the basis of the mass principle, etc. etc.
+1 yes this is how I understand it now. But I was just offering a take on the quote that may or may not make that more clear. As was phrased it was not clear for the longest time, and just got me to get hung up on the difference between the words can and will. If anything, if you insist on using that quote I think you should elaborate further like pnwarcher did or else it will not be "common sense" so to say for a new bowyer.
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I like to reduce as much as possible to one liners and then if questioned can explain. Or if it goes into some kind of glossary of terms the explanation would be there. Anyone can ask for an explanation.
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I think we are saying the same thing. In my above example of two identical uniform pieces of wood, if you place a 5 lb weight on the end, the thinner one will bend more than the thicker one...
I realize I made a typo. I meant to say "In my above example of two identical uniform pieces of wood, if you place a 5 lb weight on the end, the narrower one will bend more than the wider one."
I like to leave it a little vague on purpose, it forces us to take a little closer look at it.
I'm going to be honest. I don't get that mentality. If your goal is to help a new bowyer, you would want your advice to be as clear as possible. Einstien said "If you can't explain it simply, you don't understand it well enough". I'm not saying you don't understand it, or that you can't explain it simply. You can, but just choose not to.
...I wanted to start a thread that should be helpful to any bowyer new or experienced that we can use on the bow bench when building a bow. I have to admit that I have learned more while helping others learn because I was forced to explain something that I had been doing by habit for many years. More often than not when I started to break it down so I could better explain it I would find a small hole in my logic and something new would be revealed to me.
...Feel free to challenge and debate, I promise to stay open minded. The goal is to come up with several little jewels that can be passed along within our community. Logic and common sense are things that could apply to any weight bow of any style or length. I suspect a lot of it will be a just finding a better more understandable way of saying something.
From your own statements, I don't know why you wouldn't want to simplify things more yourself, instead of remaining vague. It seems maybe this quote is one of those instances where being open-minded on how it's phrased (not the meaning) could prove beneficial.
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Listen to the little voice that says... "that doesn't seem right" and step away.
Spend longer looking and thinking than actually removing wood.
Take off half as much as you think, you can always take more off later.
There is no such thing as working on one limb!!! What you do to one limb will automatically effect the other.
Del
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I find this a very useful thread - thanks Badger for collecting and condensing the 20 (?) golden rules.
I have many further but start with 2:
1. Be cautios with electric tools - they sometimes work faster than your brain.
2. Before any tillering and bending starts create a perfect workpiece: fix and shape your limbs and fades on +/-perfect dimensions regarding taper in thickness & width (Edit: But let the tips a bit wider to correct stringposition finally).
Cheers
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I don't get that mentality.
Greg, it's an invitation to buy the first round at the bowmakers bar. ;)
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Greg, it got your attention because it was vague. If it was all spelled out you would have likely just skimmed over it . I find this when I am teaching someone. I want to create a discussion and I want them to initiate it. For some reason it seems to stick better.
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Greg, it got your attention because it was vague. If it was all spelled out you would have likely just skimmed over it . I find this when I am teaching someone. I want to create a discussion and I want them to initiate it. For some reason it seems to stick better.
fair enough. We did discuss it after all.
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Gfugal, I'm with you and it's my approach that the clearer and shorter the telling of an idea, the better it is remembered.
1.Thickness determines safe radius.
2. Width determines draw weight.
That's all. It has worked every time for me over the last 20+ years.
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Steve I am not sure I understand all of what you said. I can say this though. I have been moving mass around in limbs for a couple years now. Trial and error. I recently built a pyramid bow that took hardly any set. Way over built in width. 2-1/2 inch at fades. Heavy on mass. 68" ntn. I did this because I had built several bows from the same tree and all took excessive set compared to my other previous bows. So I am not sure how this applies except the extra width did not take set. Arvin
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Arvin, about 4 years ago or so I was experimenting around with extra wide bows, kind of the way you did with that bow. The strange thing was that I didn't gain any mass, they were coming in physically very light because they were so thin. Not all of them but a lot of them. Kind of contradicts my own mass theory to some extent. One of them I built was about 66" long and finished up at only 1/4" thickness, I think it weighed about 18 oz.
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Never fall in Love with a piece of wood,it is just that, a piece of wood, it can break your heart and spirit, especially for a beginner. :)
Pappy
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Never fall in Love with a piece of wood,it is just that, a piece of wood, it can break your heart and spirit, especially for a beginner. :)
Pappy
Pappy, I see that pretty often. A new guy will start a bow and just work on it for weeks, in a moment of impatience or just a bad eye for tillering the bow will take a bad hinge or break and they just have a melt down. I will seldom tell someone where to take wood off because I don't want to get blamed if they screw something up. If I do I always do it with a disclaimer such as. I would do it this way but it is your bow and you decide yourself.
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I completely agree with what Clint wrote earlier... if you haven't made well-tillered bow with a simple and conservative design, why go for a sinew-backed 5 curve or a composite horn bow?
I see this all the time with the 5th graders I teach, they want to achieve the ultimate level of skill right away without starting from the beginning and paying their dues.
I tried and failed with a simple D bow design many, many times before I made my first shooter. For me, there has never been any substitute for trial and error.
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I think one of the best improvements I have made is not over thinking things or asking so many questions but just going to the shop and making bows of different designs and figuring things out on my own , its easy for me to over complicate processes by reading or thinking or asking others advice to much , but the best lessons that I have learned are by failing, Trial & error !
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Trial and error is how our ancestors did it. But it took them 5000 years ;D ;D ;D I'll go with asking questions. I think though, that just looking at the bows on here is a good substitute. You learn what a bow should look like and that's a real start. I've never built a bow with hand shock. Could be luck, could be that I don't know what hand shock is but I think it's because all the bows built by the experienced bowyers on here have skinnyish tips. I copied that.
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Yes I think we all can attest to failure making bows.Just the way it is.The way I had to get satisfied was to make at least a dozen of any type design with a certain wood.Then move on to different woods with the same procedures.That can take some time & bows but usually most settle in with a certain design that they prefer for themselves,and along with it certain types of woods too.
It can feel like groping in the dark if a person jumps too far ahead of themselves with a more difficult stressful design.Not a common sense type way,but there are some very talented bowyers on here.
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Arvin, about 4 years ago or so I was experimenting around with extra wide bows, kind of the way you did with that bow. The strange thing was that I didn't gain any mass, they were coming in physically very light because they were so thin. Not all of them but a lot of them. Kind of contradicts my own mass theory to some extent. One of them I built was about 66" long and finished up at only 1/4" thickness, I think it weighed about 18 oz.
So am I safe to say no matter where the mass is as long as it is deminishing evenly??? I understand from the BB that the density affects width. Is that not true or am I just not understanding. White woods have to be wider yes or no? Scratching my head. Also if they get to wide the boat paddle effect comes into play . Arvin
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Arvin, if you know the wood you are working with and you are satisfied with the design and the amount of set they are taking you don't need to worry about it. I like to estimate my mass ahead of time because I am always working on something different with a lot of different woods. As far as where to put the mass. The front profile should agree with the braced and drawn profile. Someone might say that is vague but I really don't think it is. Your bows always seem to accomplish this pretty well.
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Master the bend-through-the-handle bow before starting on any other design. The arc is easily checked by comparing it against any circular object.
No fooling around with trying to make a stiff handle, fade outs, recurves, decurves, etc etc. Just a simple arc. Any flat spot is obvious, any hinge is equally obvious.
It's an arc. Arc-hery. Get it?
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Know when to stop or when to say, "Close enough".
The technobabical, engineering, analytical sliderule, calculator minds we are conditioned with cause us to over-analyze or in other words - make the perfect bow. This is primitive archery. Learn to accept some flaws or at least know when the flaws aren't critical to expelling an arrow from a stick and a string. Too many "Kids Bows" could have been avoided if we stopped making adjustments. If still not satisfied, learn from it and make a better bow the next time.
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The wood speaks. You have to learn to listen with your eyes.
Study the stave. Get intimate with the humps, the bumps, the knots, the curves, the checks, the splits, the dips, etc. Plan your bow around them or utilizing them. Stay aware of those characteristics while making the bow and before taking the next steps. Then study it again. It speaks while strung or unstrung; while still and while bending.
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The wood speaks. You have to learn to listen with your eyes.
Study the stave. Get intimate with the humps, the bumps, the knots, the curves, the checks, the splits, the dips, etc. Plan your bow around them or utilizing them. Stay aware of those characteristics while making the bow and before taking the next steps. Then study it again. It speaks while strung or unstrung; while still and while bending.
I agree with you Matt, that's why I quit using my bandsaws and doing everything with my draw knife. By the time I get into tillering I know that stave pretty well.
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The front view should agree with the braced and drawn profiles.
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Use your senses.
Listen to what the stave is saying it wants to be.
Look at every inch of the limbs as they bend.
Use your fingers to feel the thickness of limbs and spots that may be thicker or thinner. I many times will close my eyes lightly pinch my limbs and slide them along feeling for uneven thickness. When I feel one I'll stop open my eyes and mark the spot. Then I'll watch that spot bend and see if my eyes are telling me the same thing my fingers are. Most times my fingers are right.
I'm still pretty new at this and agree with start simple. I still build pretty conservative bows and I'm just starting to challenge my comfort zone.
Like Pappy said it's just a piece of wood. There are many more. Don't be afraid to enjoy it and shoot it when it's done that's the really fun part.
Bjrogg
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King Osage is very forgiving and believe me I have needed my fair share of forgiveness in learning to make bows.
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In the low double digits for bows built, but this is helping me. Start with a clear intention (design statement). Consider afterwards what worked, what didn't, and why. Then start the next. Enjoy failure..
John Strunk's workflow really helped organise my approach, too. Back, sides, belly, handle. Ideally, complete one, then move to the next.. Can't say I stick solidly to it, but it helps.
Sabb
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Probably not wisdom but practical advice nonetheless. Minor tiller and weight adjustments are often best achieved by trapping backs and bellies. Keeps you from going ditch to ditch with your adjustments.
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I nominate this thread as a sticky. The advice here is some of the best ive seen in one place.
My experience holds little weight compared to these other "gems of wisdom" from the seasoned veterans. But for some reason when it comes to bow building i have to make the same mistake more than once for it to sink in. To be able to identify exactly where and why and how a mistake took place in the bow building process, and to avoid it the next time, is a thing im still working to achieve.
Nowadays i like to do the bow building process in different segments, so to speak. Someone here stated repetition is necessary to create skill, or something to that affect. For this reason, working on multiple staves and bows at the same time is the way to go for me. It saves me from the heartache of relying on one bow at a time to work out. So split a few logs into staves, take a few staves down to bow dimensions. Heat bend a few pieces. Then tiller a few bows. If at any point you get frustrated or unsure of what to do, stop, ask the PA crew for advice. You still might mess up but not as bad. In the mean time blow off some steam by picking up another log or stave and roughing it out. That way you still feel productive for the next day or so but dont rush on an important step. Also, on things like sinew backing, it helps to get multiple bows glued up and curing since its gonna take 3-6 months before you can start again, and if you make a mistake youll want a backup or two ready.
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The front view should agree with the braced and drawn profiles.
Ill need some clarification on this comment because i'm not sure i get it. How would they agree, or not agree? Perhaps they are very tolerant of each other and simply accept their differences. :laugh: Elaborate please.
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Yeah, it's like the guys who have all the jokes memorized to the point that all the have to do to get a laugh is call the joke's number. If you're new to the group, it ain't funny.
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The front view should agree with the braced and drawn profiles.
Ill need some clarification on this comment because i'm not sure i get it. How would they agree, or not agree? Perhaps they are very tolerant of each other and simply accept their differences. :laugh: Elaborate please.
A limb primarily tapered in width, and not so much in thickness, bends with a rather circular bend, while a limb that is tapered in thickness, and not so much in width, bends more in the outer limb, and is referred to as an elliptical bend. Creating these bend profiles assume an equal stress and therefore an equal strain is desired. Often an equally distributed strain is desired, but we often create exceptions. Tips and handles are strained less by design, so the the advice should be applied to the working portions of the limb
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Know when to stop or when to say, "Close enough".
The technobabical, engineering, analytical sliderule, calculator minds we are conditioned with cause us to over-analyze or in other words - make the perfect bow. This is primitive archery. Learn to accept some flaws or at least know when the flaws aren't critical to expelling an arrow from a stick and a string.
Matt, do you think the human mindset has changed that much? Wouldn't the earlier bowyers be a bit offended if they knew we saw them as primitive? Some were probably at the top of their game, proud craftsmen, and accepted flaws with the same reservations we do nowadays.
It's true, I am playing the devils advocate a bit with that comment, but in all seriousness, I often have read that the Native Americans put more time and effort into arrow building?
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There did seem to be a PC trend to imparting high tech attributes to pretty much every primitive bow style a few years ago.
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STOP a lot and look at what you are doing.......
Work in good light.
Learn to take what the stave will give you. As Jawge said, let the stave determine the design. Length width, specie, knots, etc... use them to manage expectations.
Pappy; "Never fall in Love with a piece of wood, it is just that, a piece of wood, it can break your heart and spirit, especially for a beginner." AMEN! It pays to know when to quit, when you are beaten.
Badger: "The front view should agree with the braced and drawn profiles." This is another short saying packed with info. I just spent HOURS trying to talk a beginner out of his misunderstanding that thickness helped "resist" set. Not all tillers are smooth arcs. If you want tiller help on here, please post a front view as well as a bent bow. Put the bend where it's supposed to go on that bow.
One of my favorites from Dean Torges: "Cast comes from dry wood, properly tillered."
Use ANYTHING that works for you. I am now married to the method that goes, "check, rasp, scrape, repeat", and the dogma of never pulling a bow harder than intended draw weight. I use black crayons relentlessly. I know a guy who thickness tapers his limbs by jamming on a complete set of metric wrenches down both sides of the bow. It works.
Don't overlook possibilities for dogma, but don't overlook dogma, either. I don't remember ever seeing or hearing of either a Native American bow of any style, nor European paleo or longbow made from plum, and yet the stuff in AMAZING. I can't seem to make a mistake with it.
Even dumb questions have answers.
Start with anything you can get your hands on, but buy the best tools you can afford as soon as you can after that.
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Good ones Springbuck
The cheapest sandpaper you can buy is the most expensive off the shelf belt sander included. Good sandpaper and good belts cost about 2 or 3 times as much as the cheap stuff but will outlast it 20 to 1.
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Always radius your edges and keep your limbs sanded/scraped smooth before and throughout the tillering process.
Always radius your edges before doing any heat bending also, especially while recurving tips.
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This may be related to the thickness, width, and profile discussion. But I heard something to the effect that reducing thickness reduces weight 4 times as fast as width, or was it the other way, where reducing width will reduce weight 4 times as fast as thickness. I can't remember the saying and would like someone who knows to chip in
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This may be related to the thickness, width, and profile discussion. But I heard something to the effect that reducing thickness reduces weight 4 times as fast as width, or was it the other way, where reducing width will reduce weight 4 times as fast as thickness. I can't remember the saying and would like someone who knows to chip in
8 times as fast. Strength varies directly with changes in width. Strength changes as the cube of changes in thickness. Double the thickness, you increase the strength by a factor of 2x2x2--8. Reduction of thickness makes as much change toward a weaker limb.
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It's just the opposite of how wood strength increases. Twice as wide is twice as strong, twice as thick is eight times as strong.
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I have no doubt that the beam theory is correct but an experiment I did a few years ago surprised the heck out of me. I made several extra wide bows like 3" wide for 50# osage bows, basically more than twice as wide as I normally would. The thickness should have been about 25% thinner than normal for the same weight. The thickness actually came out at about 33% thinner than normal and the overall mass which should have been higher came in at about 20% lower than my normal narrower bow. I didn't do enough tests to declare anything as fact but it really made me believe that we are straining the wood even more than I previously thought we were. Since that time I have made plenty of osage bows between 1 3/4 and 2" wide. Even at the extra width my mass seemed to come in at about what I expected. Assuming the beam theory formula is correct this could only mean we are underestimating strain on our bows.
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A bit off topic but I've been toying with a design.bend though the handle,gradually changing to a flat bow at mid limbs and down to Molly levers.from what I've seen,it makes for a fast bow with little set.thoughts?
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I have no doubt that the beam theory is correct but an experiment I did a few years ago surprised the heck out of me. I made several extra wide bows like 3" wide for 50# osage bows, basically more than twice as wide as I normally would. The thickness should have been about 25% thinner than normal for the same weight. The thickness actually came out at about 33% thinner than normal and the overall mass which should have been higher came in at about 20% lower than my normal narrower bow. I didn't do enough tests to declare anything as fact but it really made me believe that we are straining the wood even more than I previously thought we were. Since that time I have made plenty of osage bows between 1 3/4 and 2" wide. Even at the extra width my mass seemed to come in at about what I expected. Assuming the beam theory formula is correct this could only mean we are underestimating strain on our bows.
Steve, the formulas for beam strength are based on homogenous materials, which wood is not. So for wood, we have to expect and watch for variation. That means approaching the dimensions the way we do--cautiously.
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A bit off topic but I've been toying with a design.bend though the handle,gradually changing to a flat bow at mid limbs and down to Molly levers.from what I've seen,it makes for a fast bow with little set.thoughts?
A little bend through the handle is a good strategy for lowering stress on the limbs, just a little flex can give you about 4" additional draw, most of the set we pick u usually starts around 24". So, yes I like the idea and sometimes use it myself.
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My logic is a d shape in the handle bending and taking no set.gradually panning out to a rectangular cross section to distribute the load and taking a little set and stiff outer limbs for performance.thanks for your response Steve!will test this model more extensively this summer.its kinda like a Sudbury but not quite.
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Bow logic?I really can't stress enough how much more enjoyable bow building has become after I ditched the t stick!it stressed me to the max when I used one.now. Floor tiller and exercise and touch up by brace shape is my go to.takes some time but touch ,feel and sight win the day imoh!
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Badger: "I have no doubt that the beam theory is correct but.........."
I apply it to limbs of course, but really where I use this rule is in stiff sections and handles. If I have a 1/2" thick X 2" wide limb and want to narrow in a 1" wide handle, it better be 1/2" thick PLUS 1/16" to bring the stiffness up even with the limb, plus at LEAST another 1/16" to make sure it bends less than the limb, plus a tad more as fudge factor, or I know I don't have enough wood for a narrowed handle, even with an added block. Then I need to rethink the design
You gotta know what you can get away with and what you can't.
Bushboy: "A bit off topic but I've been toying with a design.bend though the handle,gradually changing to a flat bow at mid limbs and down to Molly levers." I have not done this, exactly, but the principles are sound. What I have done is a bendy handle where the limbs flatten considerably (maintaining their width), through the mid-limb where they bend the most, and then narrow considerably in the "Eiffel tower" style toward rigid tips.
Baker's Pecan bow from the TBB'S is kind of like yours, but with a fairly long, rigid middle, and barely bending inner limbs.......
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Good stuff in this thread! I don’t have much logic or wisdom to impart. I would suggest to a newcomer the importance of shooting a bow a good bit before putting a lot of time and effort into finishing work. Some pieces of wood just won’t make a long lasting, durable bow. Save yourself the emotional kick in the groin and shoot a new bow a hundred shots before you put twenty coats of true oil on it.
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Good stuff in this thread! I don’t have much logic or wisdom to impart. I would suggest to a newcomer the importance of shooting a bow a good bit before putting a lot of time and effort into finishing work. Some pieces of wood just won’t make a long lasting, durable bow. Save yourself the emotional kick in the groin and shoot a new bow a hundred shots before you put twenty coats of true oil on it.
+1 I would even add that 100 times is probably not enough. I'm planing on shooting a bow 500 times before I call it safe