Primitive Archer
Main Discussion Area => Bows => Topic started by: toomanyknots on October 26, 2010, 01:53:24 pm
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Nope they are not. They are levers. :) Just had to get this off my chest, heres a reply to a post on paleoplanet:
"Shoot, my main design is a pyramid with molly/holm tips not bending, plus reflexed. See, a pyramid design is great because it bends super evenly with very little chance of a hinge without even tillering most of the time, bending so evenly reduces set also. But it doesn't shoot very fast. A molly shoots very fast, seeing as it is a very small bow. Smaller bows shoot faster. Why is it a small bow? Because the levers on the end, like static recurves/siyahs, ARE NOT NECESSARY PARTS OF THE BOW! THE REAL BOW IS ONLY THE MIDDLE THAT SHOOTS! I think this is the correct way to look at siyahs/levers/whatever you call em. In regards to why recurves are always deemed as so fast. Now I know working recurves should probably be excluded a little bit as the recurves work a bit, but still use the same principle. It's not that a 70" longbow verses a 70" recurves results in the recurve being faster. It's a 70" long verses a 60" bow with 5" recurves results in the smaller bow being faster. The primary function of recurves has absolutely NOTHING to do with increasing the speed of a bow. In fact more mass on a bow could only decrease speed. If you think about it's just funny that we as bowyers who of all people should understand the dynamics of bows all say that "recurves are fast". I must say this again as I cannot stand the dogma that gets thrown around.
THE PRIMARY FUNCTION OF RECURVES HAS NOTHING TO DO WITH SPEED.
It is all leverage, plain and simple. Small bows stack and a 50" 60# at 28" bow , although very fast, with no recurves/siyahs/molly levers is anything but joy to shoot because of stack. Add some light molly levers on there, and there ya go. If ya wanna follow the principle of leverage farther, then you would recurve your levers, at whatever degrees results in a 90 degrees angle with the string and the recurve at full draw, with would be the strongest angle. Anything less than a 90 degrees at full draw and you start to stack. Sooooooo a lazy mans method for a good preforming bow would be...............
- Dependablity, low set, as well as ease of tiller (Or cookie cutter bow method, lazy, :) ) of the pyramid design.
- Preformance of a smaller a bow, as small as the material will allow to reach drawweight at drawlength.
- Non working recurves/siyahs/levers at such an angle to reach no more than 90 degrees at fulldraw resulting in a smooth drawing bow. Perferably
as light strong and long as functional. 5" I find usually does a great job of reducing set. 45 degrees to the bow is the only way I have tried yet."
Just saying, small bows are fast. Recurves are levers. Small bows with recurves are fast bows with levers. :)
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i know that generally, on the horn bows, the siyahs added early draw weight, but other than that, idk! lol
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"i know that generally, on the horn bows, the siyahs added early draw weight"
But they don't, thats what I'm saying. That is a misunderstanding. A small bow with the same brace height as a longer bow is going to have higher early draw weight. The siyahs are there for leverage and nothing more. A static recurve stores no energy and therefor has nothing to do with increased energy as brace.
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What!?!? Have you read the TBB's? They do more than just reduce stack on short bows. And they can be built with minimal weight in the tips. I doubt there are many straight profile bows that can touch the speed of a Marc St. Louis deflex recurve.
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What!?!? Have you read the TBB's? They do more than just reduce stack on short bows. And they can be built with minimal weight in the tips. I doubt there are many straight profile bows that can touch the speed of a Marc St. Louis deflex recurve.
Ditto, but I think he said his reflexed recurves are still faster than the deflexed recurves?
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Do you mean recurves with only reflex? The Deflex recurves I meant are his R/D recurves.
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I think recurves have the potential to be the fastest because they store the most energy. Recurves if not designed properly can also have the most problems. Mark St Louis has made many recurve self bows that exceed the 180 fps mark using the 10 grain per pound 28" draw standard. You will likley never see a straight bow that ever exceeds that number. R/d bows I believe have the potential to be just about as fast and I think in most cases are faster because they will usually have lower mass outer limbs and be more efficient. That being said I still favor the slightly reflexed straight bow designs with light weight outer limbs. They seem to be just a tad slower when optimized but much easier to optimize. Between the Molly and the pyramid the molly will ususally get the nod if properly tillered where the front virew of the bow matches the tiller shape but just slightly modifying the outer limbs on the pyramid into an eifel tower shape will get you right back even with them. Good post here! We used to have some great discussions on these things. Steve
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I am not a fan of the recurve concept on a selfbow. They are time consuming to build. Most these days build recurves with static tips which means more weight on the tips which slows the bow down. Jawge
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You are right in that they are leavers. BUT..... leavers are often used to increase speed. Put a ruler on a pencil to make a little teeter totter. First put the pencil in the middle of the ruler. Put something on one end then smack the other end down. The object will fly. Now try it with the pencil 2 inches away from the end you will smack. It will fly a lot farther. WHY?? ?? ?? Because the leaver made it travel faster.
Reflex equates to early draw weight. If the recurve (leaver) makes the tips 4" reflexed how can it not add early weight. Early draw weight equates to higher stored energy which (if the bow is designed efficient) means more energy into the arrow. More energy into the arrow means more speed.
The PRIMARY purpose of recurving is more complicated than just making a bow easier to draw. Pulling 65# requires the same energy whether the bow stacks or not. Yes, the weight builds faster at the end if the bow stacks, but it still requires 65# of pull to get it back. But by reducing stacking you increase energy put back into the arrow and increase speed.
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I do like to flip the tips a little (occasionally), but its still at a cost of more stress in other areas of the limb. The simplicity of a flat limb profile has pulled me in lately, and I'm not giving up much by doing it.
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Just throwing out a couple other questions does a set back-in -the handle or reverse riser add anything to speed?In the first tbb1 it is stated the side profile is what gives a bow its speed but according to the tbb 4 re curves can't be as fast because of the extra mass at the tips? I think that a well tillered straight forward maybe a little flip at the tips ,is a great performer-Hammertime
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Steve, Do you have a results list for WTT wood bows with a description of those bows?
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Justin's example of the mechanical advantage of levers couldn't be any easier to understand. The potential energy stored in the re-curved limb is understandable as well, however when I shoot with my friend who uses a re-curve, his bow is much louder than my plain old straight limbed selfbow that has an inch and a half of set. As far as hunting goes I'll take my quiet old hog of a bow before his noisy speed demon any old hunting day.
A question for Steve, who has seen the competition at events hosting flight bows, what bows perform the best?
Another question I have been mulling over, is should the levers be equal or unequal in length? What effect one way or the other does this have on the static fulcrum and the position of the dynamic fulcrum on a bow?
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The static recurve or "flipping the tips" makes the bow shoot a bit smoother. Big A and Greg put them through the chrono one year I think and found no gained speed but the bow was much more enjoyable to shoot.
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If you think about a coordinate plain, the bottom being draw length and the side being weight. plot out the points of each pound at each cross section.A bow with a higher mid and early draw weight will have more area under the curve, thus more force at each stage of launching the arrow.
There are trade offs to speed though, such as Lombard pointed out.
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thats the summary i was thinking of aries.. you need to plot out two different bows, to see the energy stored.
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@Badger
"R/d bows I believe have the potential to be just about as fast and I think in most cases are faster because they will usually have lower mass outer limbs and be more efficient."
I totally did not even think about reflexing in any way shape or form, :o :D ::) Reflexing definitely makes a faster bow. But I firmly believe the smaller the bow the faster the bow, and not just because of less mass. Maybe it's a mix of less mass, and a more strained bow, like a reflexed bow, say a typical reflexed laminate for example, would strain the material more than a bow of the same length and draw weight. Evident in that the unreflexed bow of the same draw weight would be thicker/or just more material to reach the same weight than the reflexed bow. The extra energy comes from the extra stain. Just like in a smaller bow, the extra energy comes from the extra strain if pulled at the same drawlength of a larger bow. Or, in case of a turkish composite, you have a very small bow, and a very heavily reflexed bow. How do those perform now? :) I really don't buy the "every design performs as well as you accompany it to the wood" quote.
"Good post here!"
Thank ya, it's the only way I really learn is to discuss stuff. Thanks for the reply. Totally didn't think about reflexing, :):):)
@ Justin
"You are right in that they are leavers. BUT..... leavers are often used to increase speed. Put a ruler on a pencil to make a little teeter totter. First put the pencil in the middle of the ruler. Put something on one end then smack the other end down. The object will fly. Now try it with the pencil 2 inches away from the end you will smack. It will fly a lot farther. WHY?? ?? ?? Because the leaver made it travel faster."
I would probably just say that moving down made it travel further. That doesn't make too much sence to me, comparing the ruler flipping the pencil to the string taking the arrow as I would not think the string cares how it get back to brace, as long as it gets back fast. Less mass, or no recurves, would take the string home faster, wouldn't they? If the arrow was shot by tip of the bow like a pencil on a ruler I would see your arguement... But no, I really don't undertand what your saying. :)
"Reflex equates to early draw weight. If the recurve (leaver) makes the tips 4" reflexed how can it not add early weight."
Totally true and not very thought out on my part. I would have to admit that my argument could only be applied fully toward static nonworking recurves on a unreflexed bow. My point is that the recurves shrinking the working bow part down (hense a recurve being more stressed, because it's bent more, because it's essentially become a smaller bow that is overdrawn. Making it faster.) Yes, most selfbow recurves, like the style associated with osage so much, kinda would be like an even mixture of recurve and reflex, although we just call it a "recurve"?, especially if the recurves uncurl when drawn it would be alot to do with reflex making higher early draw weight. But compare it to a static recurve of the same length nock to nock and I would bet the static would beat it, only for the fact of being over drawn.
"But by reducing stacking you increase energy put back into the arrow and increase speed."
Do you mean because the energy gets distributed out more evenly for the draw it gets put into the arrow more? How would that work? Because if you mean early draw weight being higher you could reflex the bow or brace it higher than normal and get higher early draw weight, right?
@hammertime
"Just throwing out a couple other questions does a set back-in -the handle or reverse riser add anything to speed?"
Well if I think about, I would say that it would add speed by working the limbs more. Like if the bow was smaller. :):):)
@aero86
I didn't mean to sound like a duesh, I just wanting to point out something that is probably obvious to everyone else but for me was not, which is that recurves, as well as reflex with working recurves, but recurves/siyahs/levers all make a faster bow because of shrinking a bow really, stressing the limbs more because less of the length of a bow is working. Not that recurves by them selfs make a faster bow, (what I thought at first, even though it didn't make sence :) ). Like if you had two 70" bows that both pulled 50#. And on one you added 5" recurves, but instead of recurving back the limbs, you just added the 5" recurves onto the ends of one bow, making it a 80" bow nock to nock. Which would most likely shoot alot slower than the bow without the siyahs.
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@ Justin
That doesn't make too much sence to me, comparing the ruler flipping the pencil to the string taking the arrow as I would not think the string cares how it get back to brace, as long as it gets back fast.
"But by reducing stacking you increase energy put back into the arrow and increase speed."
Do you mean because the energy gets distributed out more evenly for the draw it gets put into the arrow more? How would that work? Because if you mean early draw weight being higher you could reflex the bow or brace it higher than normal and get higher early draw weight, right?
A ruler is a leaver and a perfect example of physics. The laws of physics don't care if it is a string attached to a recurve, a ruler on a desk or a dart on an atlatl.
It is using leavers to eliminate histersis (the loss of energy from stacking) in the limbs and transfer the energy that would be lost into the arrow.
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@ justin
Oh, thank you for clarifying that. I still don't fully understand exactly how it works but I am sure you are right, I think I am just thinking too hard... :)
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I think you are misunderstanding a lot of the physics at play. Justin's reference about the pencil and ruler is about leverage. Bow limbs are just levers...that's it. Short bows in straight profiles are not faster than longer bows. Of course there is a point of diminishing returns but typically longer straight profile bows are faster at least according to the info in TBB4. Also you seem to think that strain equals more speed according to the TBB's this isn't true either. The more you can reduce stress to the wood the better the bow performs. "Perry" Reflex is an example of this. The theory is that by gluing the bow up in reflex you are taking strain off the wood and placing it in the glue line.
"One of the cruel realities of bow design is that shorter straight bows can't be as fast per pound as longer straight bows even at equal draw length. Bewteen 35" and 60" possible performance rises roughly 1 fps per inch of bow length. Cast rises slowly from there to around 68" then only minor improvement from there to 80" and only then if given a more elliptical tiller."
-Tim Baker
Traditional Bowyer's Bible IV
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I was typing while you were posting.. ;D
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"One of the cruel realities of bow design is that shorter straight bows can't be as fast per pound as longer straight bows even at equal draw length. Bewteen 35" and 60" possible performance rises roughly 1 fps per inch of bow length. Cast rises slowly from there to around 68" then only minor imporvement from there to 80" and only then if given a more elliptical tiller."
Whaaaaaaaaaaaaaa???? Way ta turn my world upside down... :o
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@ justin
Oh, thank you for clarifying that. I still don't fully understand exactly how it works but I am sure you are right, I think I am just thinking too hard... :)
Toomanyknots, to bring home what Justin is saying about levers, take yourself an apple in your hand raised to shoulder height and flick you wrist. See how far your apple goes. Now take your apple and poke it onto the end of a two foot long stick, raise your hand to the same level as before, only now you are holding the stick with the apple on the end. Flick your wrist with the same force as before, and note how much further your apple went. What changed? Same energy, same weight, but the mechanical advantage of a lever has increased your cast. You moved that same weight over a greater distance in the same time period. And if you want to test the diminishing returns factor, just keep launching your apple with a longer and longer stick, remember to apply the same amount of force each time. Eventually due to the weight/mass of your stick, you will not be able to maintain the same time period with the same amount of force, thus losing cast. The experiment will clarify for you the advantage of the lever, and the point at which you get diminishing returns.
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wow, good example lombard!
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.... But I firmly believe the smaller the bow the faster the bow, and not just because of less mass.
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Well, if a bow is too short, it will simply not have enough mass to store energy; I - with my little experience - do also believe, that a stacking bow is slower that a no-stacking bow. I also believe that early draw weight means an elongated acceleration to the arrow, which means a faster flight, which MIGHT have to do with recurves. Sure, the recurves themselves don't store energy.
JMO
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Steve
Why do you think r/d bows are faster than slightly reflexed. If the total amount of reflex is the same is the r/d still faster?
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Bows are not complicated but they do follow certain rules of physics. A longer bow will always store more energy because it maintains lower string angles. Very little of the weight gain you experience when drawing back a bow has to do with the wood compressing, almost all of it is due to increasing string angle and lowering your leverage.
For the most part it seems straight bows betwen about 66" and 68" have recorded the fastest speeds for straight bows. Longer bows do store more energy but the efficency starts dropping off at this point when you are testing with a 10 grain per pound arrow. As the arrow weight goes up so does the efficiency so bows shooting heavier arrows are better off to concentrate on storing more energy, either through making the bow longer or adding recurves for instance and lowering the string angles.
Flight bows that shoot very light arrows can be built much shorter and made to store less energy as they are more concerned with efficiency and higher dry fire speeds. Most of us don't concern ourselves with something called virtual mass, but virtual mass refers to how much more the arrow could have weighed to attain the same speed if it were 100% efficient. Flight bows like to have a very low virtual mass figure.
After testing out literaly hundreds of bows I still could not tell you what I think is the best design. Elbs, mollies, pyramids and regular old american long bows all built with just a hint of reflex and refined a bit in design will all perform about the same at around 172 fps if everything goes just right. There will alwasy be exceptions that will out do this but for the most part this seems to be about it. Laminates will average about 8 fps faster and r/d and recurve designs will bump that up another 8 or so fps if everything is just perfect.
Besides light outer limbs the most important thing in performance is to minimise the damage you do to the wood when tillering. Damage will start happening even before set becomes apparent. A perfect bow ( almost non existent) will spring back to it's pre braised shape the instant is is unstrung. Excersising in a bend after wood removal becomes unneccessary because if you have to excersize it in it is because you are crushing cells. A perfect bow would have no memory of ever being bent. I have only succeeded in doing this one time but the closer you come the better. This is the advantage fiberglass has on wood, fiberglass cells don't crush. Steve
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...This is the advantage fiberglass has on wood, fiberglass cells don't crush. Steve
Steve, it seems that cells heat treated bamboo crush very little (at least for quite a long time, or for many many shots...); would you say that is true from your experience??
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PS: this is a really good discussion going on here!
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NTD- I was refering to his reflexed static recurves, not the R/D ones. Like the one he did in his article "The Burnt Offering".
How much energy a bow stores and how well the bow transfers that energy to the arrow seem to be the only two things that affect performance. Which Steve explained, illustrated, and made very clear :)
Short bows are slower. All they have going for them is lower mass than longer bows, so slightly higher efficiency. Of course, since they store less energy because the cells are crushed so much more, there's no net gain. The converse being true for longer bows. More stored energy, but more mass. Most bows balance it out, get leverage, low mass, and low vibration working on the limbs to increase the mechanical efficiency while making sure there's a little reflex or as little string follow as possible to maximize energy storage without overstressing the limbs. The result being a good performer (if done right).
All of that is just a summation of the vast amount of info from the Bow-experts who contributed to TBB vol. 4. Once accepted, or even just tested, becomes readily apparent. "Black Betty", "Expectations", and even "Talea" were built with this in mind over the lsat few months and their performance exceeded most of the bows I'd been building for years prior :)
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Something that I think is very cool but most modern bowyers won't admit to or don't realize is that many of the recent gains in performance by modern bows came from using the principles that primitive bowyers have been using for years. Reverse wedges in the outer limbs to stiffen the tips, power lams and more aggressive limb tapers for more elyptical tillers and obviously narrowing the outer limb. They have also discovered that the tiller shape needs to match the front view of the bow. We don't neccessarily use the wedges because we carve our wood into the tapers we want.
The fastest modern bows in the world right now are about tied between the recurve and the r/d longbow hybrid. They are shooting right at 200 fps with 28" draws and 10 grain per pound arrows, 3 years ago about 190 was the fastest with the fastest primitive bows running neck and neck with them.
Primitive bow performance is not nearly as repeatable at that level and only a few specimens crop up now and then that can match that. Seems like the same bowyers are the ones that are producing those specimens so their is something to it. Steve
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Steve, Ill bet those guys have broken more bows than most have built.
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Justin, no doubt, LOL. I have settled into more dependable designs with an occassional foray into the world of broken bows with hopes of breaking records. I have gotten to the point where I like a primitive bow to look like a primitive bow. As long as it performs well for it's design it makes me happy. Playing around with high performance is a good excersize I think for building good dependable bows.
Tim Baker used to show up for our monthly meets with a stack of red oak boards. he would usually convert a couple of them into very good shooting bows by the time the day was up. Not record breakers but consistently good shooters. I always thought this is what being a bowyer is all about, getting to know wood well enough to make it behave, simple but very effective. Steve
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Justin, no doubt, LOL. I have settled into more dependable designs with an occassional foray into the world of broken bows with hopes of breaking records. I have gotten to the point where I like a primitive bow to look like a primitive bow. As long as it performs well for it's design it makes me happy. Playing around with high performance is a good excersize I think for building good dependable bows.
Tim Baker used to show up for our monthly meets with a stack of red oak boards. he would usually convert a couple of them into very good shooting bows by the time the day was up. Not record breakers but consistently good shooters. I always thought this is what being a bowyer is all about, getting to know wood well enough to make it behave, simple but very effective. Steve
I really like that quote, Steve. :)
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i forgot about the whole discussion when i read someone having monthly bow building meets .... im the only idiot building these things for a couple hundred miles that i know of !
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"im the only idiot building these things for a couple hundred miles that i know of !"
Welcome to my world ken.
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Me too... :(
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That's why we are all here on PA! ;D 8) You really should have been here(in wood bow building world) 25 years ago. You think you live in a bow builder's desert now. ::)
Discussions like this, with folks that have put in the blood, sweat and tears over the years are priceless but they are also what feeds the wood bow revolution. Look how far wood bows have come in the last 10 years. Look at the BOM each month. I am truely amazed at not only the numbers of incredible bows each month but the numbers of successful first timers. Most of us guys that have been around for a while screwed up lots of good wood just trying to get something that even looked like a bow.
Practical experiences from the students of TBBI, II and III evolved into what was written into TBIV. Some of the "shocking" theries about building bows from whitewoods in those days have developed into some of the fastest wood bows and world class flight shooting bows today. Badger's Mass Principle, Marc's heat treating and even Tim Baker with his Design and Performance Revisited were all fueled by the enthusiasm generated by us; the lowly wood bow builder.
So KEEP IT UP!!! 8)
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i have to agree Pat , things really changed. and i've been trying to do my part at pushing the envolope and try new things. a year ago i couldnt make a 70 inch bow that stayed together and now im getting sub-50inchers that full draw.and trying different wood combos and apps.... and lovin every minute !! ;D
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ken, wish i had the time to do what youve done! been almost a year since i started and have only made a couple 4 bows! lol
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i forgot about the whole discussion when i read someone having monthly bow building meets .... im the only idiot building these things for a couple hundred miles that i know of !
If you cant find em, convert em, thats been my method so far lol ;D
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I have ejoyed reading this thread, that I am sure has only scratched the surface of what some of you guys know.
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"That's why we are all here on PA! Grin Cool You really should have been here(in wood bow building world) 25 years ago. You think you live in a bow builder's desert now. Roll Eyes
Discussions like this, with folks that have put in the blood, sweat and tears over the years are priceless but they are also what feeds the wood bow revolution. Look how far wood bows have come in the last 10 years. Look at the BOM each month. I am truely amazed at not only the numbers of incredible bows each month but the numbers of successful first timers. Most of us guys that have been around for a while screwed up lots of good wood just trying to get something that even looked like a bow.
Practical experiences from the students of TBBI, II and III evolved into what was written into TBIV. Some of the "shocking" theries about building bows from whitewoods in those days have developed into some of the fastest wood bows and world class flight shooting bows today. Badger's Mass Principle, Marc's heat treating and even Tim Baker with his Design and Performance Revisited were all fueled by the enthusiasm generated by us; the lowly wood bow builder.
So KEEP IT UP!!!"
Hell yes pat!
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Practical experiences from the students of TBBI, II and III evolved into what was written into TBIV. Some of the "shocking" theries about building bows from whitewoods in those days have developed into some of the fastest wood bows and world class flight shooting bows today. Badger's Mass Principle, Marc's heat treating and even Tim Baker with his Design and Performance Revisited were all fueled by the enthusiasm generated by us; the lowly wood bow builder.
So KEEP IT UP!!! 8)
Yes, and thatīs why we are waiting for the TBB V O:) ;D
Very nice words Pat B
acker
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recurves may not always be faster, but a good recurve produces a lot of stored energy and good string angle which makes for comfort and ease of drawing and aiming whereas a fast straight bows that gets harder to pull as you draw is not such a pleasant experience to shoot.....in my opinion
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a fast straight bows that gets harder to pull as you draw is not such a pleasant experience to shoot.....in my opinion
Most of the faster straight bows have low string follow, which means it won't stack. Unless it's toes over the edge, bows with one good quality usually have several others :)
Steve- I'm just starting to tinker with glassies, and by my fifth and sixth I'd got a design that kicks the pants off of some of the store-boughts. Every design characteristic I built into them came from wood bows too ;) Now to transfer some of that back to woods to create monsters of shooting euphoria, hahahaha! >:D
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recurves may not always be faster, but a good recurve produces a lot of stored energy and good string angle which makes for comfort and ease of drawing and aiming whereas a fast straight bows that gets harder to pull as you draw is not such a pleasant experience to shoot.....in my opinion
Good string angles on the limb can still pinch at the finger. :o
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OK, so I just read this whole post. Couldn't stop! Great discussion and I thought I would see if anyone has anything to add or revise since 2010.
And as always, thank you :)
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I don't feel qualified to comment on this. Minus one thing- a recurve more or less acts as an adjustable lever in my understanding. It makes the bow shorter(and higher weight) when at low draw length. Later on it makes the bow longer(and lower weight) when at longer draw length. so it reduces stack by adjusting the length of the bow relative to string angle.
Thats my understanding. I think this is a great thread... I learned a lot. I think I am going to make a molly bow ;)
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I just read the whole thing too.
For what it's worth my thinking on recurves goes a little like this.
The whole point of recurving is to reduce string angle leading to more stored energy over a straight limb design.
More stored energy is good but can be lost to excess weight in the tips.
Recurving also increases strain over a straight limbed design.
Increased strain = crushed belly cells which in turn reduces the return speed of the limbs.
To lower overall strain but still keep the benefits of reduced string angle deflex the limbs near the handle and reflex the outer limbs to blend into the recurves.
I agree with Badger 100% the keys to fast bows are simple. Low string angle, low weight outer limbs and more important than anything - FRESH wood.
The fastest bows i've made are reflex/deflex recurves. The best shot 212 fps with a 8.9 grain/lb arrow and that was without an optimised string but the bow was still 'fresh'. It has since been shot a lot and now shoots 185fps @ 10gpp. It is an absolute dream with literally no handshock and so quiet for a recurve.
I have been planing on trying to really optimse that design but getting good enough staves is more than a mild problem... :) and then there is the time needed.
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Statics are sexy, who cares how fast they are!
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Haha, I remember this post. ;D Sadly I do not remember what I was on when I made it, :o.
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I like static recurves only for their looks I don't care much about how fast they are
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Statics are sexy, who cares how fast they are!
Can't argue with that ;D
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Heck ill stir the pot.
RECURVES ARE NOT FAST!"
Yes they are :)
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Yup....recurves are fast...and sexy to boot 8)
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I too have learned a little from this thread, and I haven't been so amused either. keep em coming, who doesn't like those curves. >:D >:D >:D O:)
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I've made recurves, reflex/deflex, and straight limb bows and to be honest I haven't noticed much performance difference between these designs. But I haven't run them through a chrono either so maybe I'm missing something. I just make what I make because I feel like it.
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What Gordon said +1 :)
Pappy
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I don't understand all this sentiment about 'I don't care how fast they are' sort of talk. If you don't care how fast your bows are just go and cut a green branch and tie a string on it, hold it in the right place and bingo.....you've got a bow. It won't be very fast but it would probably get the job done :)
If people really didn't care how fast their bows are then almost by definition they wouldn't care if it's the slowest bow on the planet (taken the point to its logical destination).....and I KNOW this isn't true of anybody who makes good bows. You don't make a good bow by chance (or not often anyway!) which proves that you are putting a fair amount of brain power and effort into the job. Who wants to waste their time by making slow bows? As with all things in this world there are
What fires the drive to make more and more bows?
It's the desire to make something you are proud of in one way or another dependant on what criteria 'pushes your buttons'.
For me I like making the very best bow that I can. Performance AND beauty all wrapped up in the same package. Ever since my first one it's been a long journey learning how wood behaves in different designs, what factors affect arrow speed and general shootability etc etc.
At the end of the day making wooden bows is a fasinating craft that can be all things to all men.....and has been for a long time. As long as you are having fun doing it that's all that matters.
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agree with papy and gordon build and shoot what you enjoy . but i will say the fastest bows ive made were all recurves. also agree with pat the wood bow world is alot different now since alot of great books were pened and the net came along.
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I'm pretty sure I understand how recurves improve the string angle on shorter bow but I'm not sure I quite get the science behind how a recurve makes a bow faster. Could any of you who believe that recurves are faster please explain in clearly or point me towards a good explanation? I don't say this cynically, I would really be interested in hearing a convincing explanation because I find myself fumbling around this topic in conversation fairly often.
That being said, I think that I appreciate the fact that this issue isn't totally clear cut. One thing I like about the world of wooden bows is the incredible diversity of styles and designs that we see. If there was a clear difference between recurves and straight bows then the vast majority of us would only be making recurves but as it stands we make all kinds of bows and they all somehow manage to get the job done.
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Cut TMK a little slack. He wrote this years ago and just admitted that he didn't know what he was on when he wrote it. I think the conversation has moved beyond the original post and is now just discussing the supposed benefits of recurves.
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A recurve bow has tips that curve away from the archer when the bow is strung. By definition, the difference between recurve and other bows is that the string touches a section of the limb when the bow is strung. A recurve bow stores more energy and delivers energy more efficiently than an equivalent straight-limbed bow, giving a greater amount of energy and speed to the arrow. A recurve will permit a shorter bow than the simple straight limb bow for a given arrow energy and this form was often preferred by archers in environments where long weapons could be cumbersome, such as in brush and forest terrain, or while on horseback.
Recurved limbs also put greater strain on the materials used to make the bow, and they may make more noise with the shot. Extreme recurves make the bow unstable when being strung. An unstrung recurve bow can have a confusing shape and many Native American weapons, when separated from their original owners and cultures, were incorrectly strung backwards and destroyed when attempts were made to shoot them.[1]
From Wikipedia.
Weylin, the science behind the recurve-
When you string a normal bow, the string is attached at the ends of the limb, and does NOT contact the limb in ANY way along its length. Therefore the length of the bow remains constant during the draw, resulting in the weight increasing in a exponential curve.
When you string a recurve, the string contacts the limb. It shortens the bow due to that contact- Diagrams are far easier than words.
I will draw them while I eat...
Anyway, A recurved bow lengthens while it is drawn. This results in higher-early-draw weight, and lower full-draw weight. If you straighten out a recurved bow, it will be weaker- the limbs which were reflexed are now straight, resulting in them being more flexible.
A recurve bow-limb is stiffer than a normal bow limb of the same weight and length, because it has reflex near the tip, and the tips do not bend, resulting in what would be a longer bow. A molly bow is similar to a recurve, but because it does not have the early draw weight, it stores less energy. More or less, a recurved bow lengthens when drawn to compensate for string angle rising, resulting in little to no stack, storing more energy than a non-recurve bow.
To be continued.
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I like recurves because they always end up with a smoother draw due to the early draw weight.
The other benefit I find is the lower string angle which also reduces stacking and provides for more leverage effect....in the same way that an ordinary lever allows one to lift more weight than he could normally handle.
ts true though that if the materials are unable to take the added stress of the recurves, then the recurves will make the bow take excessive set.
just my humble opinions....thought I'd throw in my twopence worth...
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I like recurves because they always end up with a smoother draw due to the early draw weight.
The other benefit I find is the lower string angle which also reduces stacking and provides for more leverage effect....in the same way that an ordinary lever allows one to lift more weight than he could normally handle.
ts true though that if the materials are unable to take the added stress of the recurves, then the recurves will make the bow take excessive set.
just my humble opinions....thought I'd throw in my twopence worth...
You have a great point. But a deflex recurve is a pretty dang good bow.
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yes Squirrell I agree....I would include this in my defenition of recurve, its a just a long recurved limb....where the whole limb is recurved
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yes Squirrell I agree....I would include this in my defenition of recurve, its a just a long recurved limb....where the whole limb is recurved
A whole recurved limb is called reflexed, I think. But don't quote me on that.
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Cut TMK a little slack. He wrote this years ago and just admitted that he didn't know what he was on when he wrote it. I think the conversation has moved beyond the original post and is now just discussing the supposed benefits of recurves.
Eh, I deserve it anyway I'm sure, ;D. If I recall I was trying to open a discussion of exactly how a recurve works, in a not so elegant way, or my understanding of one at the time at least. I have no idea where I got "shorter bows are faster" though, :o. My current understanding of recurves, and especially contact recurves, is that they have a more even force draw curve, with more early draw weight than a flatbow. The limbs have to bend more to reach the same brace height (bending more means storing more energy). In the first 10 - 15 inches or so of draw the string is touching the limbs. When the string lifts off the limbs, the draw weight stops increasing as fast, (like they have effectively "become a longer bow") resulting in a smoother draw. And of course the string angle of the recurves adds to this as well, but they are both a factor, string angle alone is not responsible for the smooth draw of a recurve I think. The increased speed is a result of the increased early draw weight, smoother force draw curve (due to string lifting off recurves at near full draw), and leverage from good string angle imo. Do I got it right yet? LOL I guess I will check back in a couple years to see how I have embarrassed myself further.... ;D
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Discussions of this type are awesome and as a new guy it is an opportunity to pick some brains and see if I am even near any of the same thinking of some more seasoned folks. Of course, some brains at some times may be a little more shall we say, uh elevated (TMK). I am just glad you made the post so I could read and learn. I have yet to make a real recurve other than just mildly flipped tips so it is something I am wanting to do and curious about the actual benefits of. Thanks everybody. Doob
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some brains at some times may be a little more shall we say, uh elevated (TMK).
I honestly think you may be giving me too much credit,... by stating I have brains at all, :). After re-reading this thread just now, there really were a lot of great replies and insight/info...
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some brains at some times may be a little more shall we say, uh elevated (TMK).
I honestly think you may be giving me too much credit,... by stating I have brains at all, :). After re-reading this thread just now, there really were a lot of great replies and insight/info...
Well, you make some awesome bows so you must have something on the ball. Keep em comin bro. ;D
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Toomanykots...I removed my rashly made reply, I should've read the whole thing better before chimming in......sorry about that....It is a good thread and its good you started it....and its very good you are a humble guy...
Dave