In your defense many guys on here are telling someone who has trouble with his horn belly popping off to just try to glue it back on to the sinewed core.
I guess the performance of your bow would have me saying it's a good question why the bothered switching to composites if they don't even perform as well as a wooden bow.
On a sidenote regarding the Karpowicz style bow, is it really any different than the Hickman patent bow except for the shrunken handle length?
http://webzoom.freewebs.com/mayflowerar ... %20Bow.pdf
Ancient bows from Mongolia from an exhibition in Bonn Pt. 3
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Patrick Menzies
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Uli
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I dont have as much experience as you but just some thoughts..
the "traditional" way that has been practiced until today in china, korea, mongolia and turkey is always sinew = last step or ?
all the composites are extremely reflexed during manufacture:
isn't composite making like the modern engineering principle of pre- tension and tension-backing (in static construction for example)
with horn after sinew I imagine a loss of the advantage of reflexing the bow during manufacture.. nowadays the bow will work
the "traditional" way that has been practiced until today in china, korea, mongolia and turkey is always sinew = last step or ?
all the composites are extremely reflexed during manufacture:
isn't composite making like the modern engineering principle of pre- tension and tension-backing (in static construction for example)
with horn after sinew I imagine a loss of the advantage of reflexing the bow during manufacture.. nowadays the bow will work
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Fenris
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Interesting point. In fact the opposite may be true. According to what Adam said in another thread the reflex added by contraction of sinew may contribute only little to the overall performance of the bow (correct me if wrong). More important is the step in glueing the horn reflexed on the bow (pretension). Since the horn shows significantly less kreeping than sinew does this reflex may contribute much more to the preload of the bow (like in a korean bow). For this advantage the sinewed bow has to be allowed to reflex mor during drying, adding reflex that can be fixed by glueing the horn afterwards.
As a negative effect, this may decrease the stability of the bow an it may knock over (as described for korean bows by Grayson).
Kevin
As a negative effect, this may decrease the stability of the bow an it may knock over (as described for korean bows by Grayson).
Kevin
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Adam Karpowicz
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All materials in the composite are typical organics and do not behave in a predictable manner of the modern laminations. Most importantly they are not completely elastic and greatly affected by time (to creep under pressure), by moisture and by temperature. This may be a blessing or a curse - a clever bowyer can learn to manipulate them for the best performance, someone else may ruin the bow without even knowing it. This is why I would rather slavishly follow the original methods.
For example sinew: when the sinew/glue combination dries, it builds up internal "tension" or strain within itself. It is because the shrinkage during drying on the core of bow is restricted. If the core is flexible enough, the strains may be relieved when the bow pulls itself into reflex. Or if the support for the layer is rigid, then the strains are not relieved as much. What happens exactly and how exactly the performance or the draw weight is affected is difficult to predict without experimentation.
Kevin is correct in pointing out the reflex during glue-up. The ancients used a notch or a hole in a bench to bend wood - then one usually has a sharper bent at one end (for the siyah or grip splice) with the rest of the lath curved to some degree, whether deliberately or not. In fact the Koreans make the bamboo curved, also Turks and Manchu as well bent their cores (according to the Chengdu article). The horns were then glued onto the curved core and at the end, after sinew, the bows' tips were touching or crossed. It may be that Mongol bows were made with the laths straight, but since there is more evidence the other bows were made curved, then why do it? It is like deliberately adding deflex to a bow. The glued-in reflex surely adds to the performance of bows.
And the horn itself: when pressed flat at high enough teperature it will stay that way forever. Was it done in old bows? In some of them yes, but what was the temperature? Was it low enough so that the horns reversed back to reflex once heated to glue on the curved core? Probably. Then the horns will work harder in a bow to boost the performance again. Horn taken from the side walls has its grain partly diagonal on the bow, which will reduce its modulus by maybe 20% (just a guess - cross grain is half the modulus). The bow will loose a few pounds.
I undestand now what you meant JR that I should know better than argue against modern engineering. The truth is I do not know and there is no enginner as yet who knows. I'd rather stick to the proven methods, especially so in doing important research such as this.
Adam
For example sinew: when the sinew/glue combination dries, it builds up internal "tension" or strain within itself. It is because the shrinkage during drying on the core of bow is restricted. If the core is flexible enough, the strains may be relieved when the bow pulls itself into reflex. Or if the support for the layer is rigid, then the strains are not relieved as much. What happens exactly and how exactly the performance or the draw weight is affected is difficult to predict without experimentation.
Kevin is correct in pointing out the reflex during glue-up. The ancients used a notch or a hole in a bench to bend wood - then one usually has a sharper bent at one end (for the siyah or grip splice) with the rest of the lath curved to some degree, whether deliberately or not. In fact the Koreans make the bamboo curved, also Turks and Manchu as well bent their cores (according to the Chengdu article). The horns were then glued onto the curved core and at the end, after sinew, the bows' tips were touching or crossed. It may be that Mongol bows were made with the laths straight, but since there is more evidence the other bows were made curved, then why do it? It is like deliberately adding deflex to a bow. The glued-in reflex surely adds to the performance of bows.
And the horn itself: when pressed flat at high enough teperature it will stay that way forever. Was it done in old bows? In some of them yes, but what was the temperature? Was it low enough so that the horns reversed back to reflex once heated to glue on the curved core? Probably. Then the horns will work harder in a bow to boost the performance again. Horn taken from the side walls has its grain partly diagonal on the bow, which will reduce its modulus by maybe 20% (just a guess - cross grain is half the modulus). The bow will loose a few pounds.
I undestand now what you meant JR that I should know better than argue against modern engineering. The truth is I do not know and there is no enginner as yet who knows. I'd rather stick to the proven methods, especially so in doing important research such as this.
Adam
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Kviljo
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I am very happy to finally see you here, JR! I'm certain that you will enjoy the good scientific atmosphere here, once the somewhat heated welcome has settled a little 
When the exhibition catalogue appears in my mail box any day now I will read it with much interest! If there are not complete reconstructional information on the bows in it, I certainly hope that you will publish something like this some time. Wouldn't it be great to see more reconstructions of these bows - to add to the interpretation of them?
Your method of first tillering the core and sinew before applying the horn seems to be a legit way of getting a proper tiller on designs that one does not know the limb taper of. I have used a similar method to understand the tiller of the norwegian two-wood bows in my masters thesis. My limited experience with horn bows tell me that there are some important technical advantages and historical evidence pointing to the "traditional" way of gluing the horn to the core before applying sinew.
1: The sinew layer of all preserved horn bows that I have seen, also cover the edges and at least a little of the horn belly - indicating that the sinew layer have been applied towards the end of the construction.
2: The Korean and Chinese traditions which have been documented while they were and still are alive, point in the same methodological direction. Traditions like these should not be undervalued as analogies in archaeology.
3: A core that is still oversized while glueing the horn, acts as a stable platform and gives the bowyer good control of the design and the stability of the bow.
4: Ancient bowyers have all been part of a craftmanship tradition of making only a very few types of bows, which have given them a very detailed and exact knowledge of the dimentions and construction of the bows. Tillering by dimention adjustments have most likely been far less necessary for them, compared to our modern way and interest in making all of the worlds types of bows in a very short time.
When the exhibition catalogue appears in my mail box any day now I will read it with much interest! If there are not complete reconstructional information on the bows in it, I certainly hope that you will publish something like this some time. Wouldn't it be great to see more reconstructions of these bows - to add to the interpretation of them?
Your method of first tillering the core and sinew before applying the horn seems to be a legit way of getting a proper tiller on designs that one does not know the limb taper of. I have used a similar method to understand the tiller of the norwegian two-wood bows in my masters thesis. My limited experience with horn bows tell me that there are some important technical advantages and historical evidence pointing to the "traditional" way of gluing the horn to the core before applying sinew.
1: The sinew layer of all preserved horn bows that I have seen, also cover the edges and at least a little of the horn belly - indicating that the sinew layer have been applied towards the end of the construction.
2: The Korean and Chinese traditions which have been documented while they were and still are alive, point in the same methodological direction. Traditions like these should not be undervalued as analogies in archaeology.
3: A core that is still oversized while glueing the horn, acts as a stable platform and gives the bowyer good control of the design and the stability of the bow.
4: Ancient bowyers have all been part of a craftmanship tradition of making only a very few types of bows, which have given them a very detailed and exact knowledge of the dimentions and construction of the bows. Tillering by dimention adjustments have most likely been far less necessary for them, compared to our modern way and interest in making all of the worlds types of bows in a very short time.
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redhawk
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The traditional way has proved its merits for centuries.
Any other way of making hornbows is a totally misunderstanding of hornbowery.
Hornbow- making is a chemical process( above all a polymerisation)
Sinew- backing the core/horn- lam makes the reflex.
Sinew- backing the core makes a reflex too, but then adding the horn is reversing the whole process.
That?s why I have to call your hornbows sinew-backed bows with a horn- decoration. Believe me, a hornbow made like this would be more efficient without the horn( just adding physical weight).
I found it heavily careless to post your method as a hornbow- basic in a book, which is really expensive.
We?ve had this discussion several times and you seem not to understand or you?re not willing to admit an error.
Good luck with your hornbows
Is there any additional opinion about JR?s hornbow- basics?
Michael
Any other way of making hornbows is a totally misunderstanding of hornbowery.
Hornbow- making is a chemical process( above all a polymerisation)
Sinew- backing the core/horn- lam makes the reflex.
Sinew- backing the core makes a reflex too, but then adding the horn is reversing the whole process.
That?s why I have to call your hornbows sinew-backed bows with a horn- decoration. Believe me, a hornbow made like this would be more efficient without the horn( just adding physical weight).
I found it heavily careless to post your method as a hornbow- basic in a book, which is really expensive.
We?ve had this discussion several times and you seem not to understand or you?re not willing to admit an error.
Good luck with your hornbows
Is there any additional opinion about JR?s hornbow- basics?
Michael
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jack farrell
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I would like to switch the focus of this discussion a moment.
Imagine for a minute that a museum in Germany got access to a previously unknown violin which was one of the oldest in the world and also of very unusual design. Then, by some unknown process, they decided to let one violin maker of their choosing investigate this violin while at the same time collecting admission fees to see said instrument.
Now, other violin makers, musicians and historians are wanting to know the specifics of this instrument but the information has not been forthcoming.
What would they do? If it was me, I would want to know what could be done to make the information more public. Of course, the first reaction of the museum would be that the instrument makers and musicians should be grateful and humble that they are given any information at all at the same time that the museum continues to collect entry fees.
I think that various symphonies and musician unions would begin to put pressure on the museum to be more forthcoming and allow a number of different makers and players to investigate and discuss freely what they see. This would in no way inhibit the museum from getting their share. Controversy sometimes helps. Maybe the institution is publicly funded. Maybe there are donors who would not like the current process. Maybe publications who need support from the musicians would apply pressure. Maybe some negative public relations or influential pressure would be brought to bear. Maybe the museum does not know the level of interest in the violin nor consider it their mission to educate the people they are serving.
I would ask Steven to indulge me to allow this story to remain as a legitimate democratic means of obtaining information on instrument making.
Imagine for a minute that a museum in Germany got access to a previously unknown violin which was one of the oldest in the world and also of very unusual design. Then, by some unknown process, they decided to let one violin maker of their choosing investigate this violin while at the same time collecting admission fees to see said instrument.
Now, other violin makers, musicians and historians are wanting to know the specifics of this instrument but the information has not been forthcoming.
What would they do? If it was me, I would want to know what could be done to make the information more public. Of course, the first reaction of the museum would be that the instrument makers and musicians should be grateful and humble that they are given any information at all at the same time that the museum continues to collect entry fees.
I think that various symphonies and musician unions would begin to put pressure on the museum to be more forthcoming and allow a number of different makers and players to investigate and discuss freely what they see. This would in no way inhibit the museum from getting their share. Controversy sometimes helps. Maybe the institution is publicly funded. Maybe there are donors who would not like the current process. Maybe publications who need support from the musicians would apply pressure. Maybe some negative public relations or influential pressure would be brought to bear. Maybe the museum does not know the level of interest in the violin nor consider it their mission to educate the people they are serving.
I would ask Steven to indulge me to allow this story to remain as a legitimate democratic means of obtaining information on instrument making.
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Redhorse
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- Location: Sweden
Actually it is easy, if we don not like to make the "thing" the old way, well made it from glas and laminited wood and gelcoat. Use computers and other stuff for cutting and so on.
I did read some Swed build a house from stoneage. They did use tractor to make the polehole, crane lifting the loggs and more. Because they was not strong enough to do it by hand. At the same time I was building a shelter for my machines the same way and did it alone by hand, simply inch by inch with a rope I lift the loggs. With two or more man the loggs could been much heavier then what they did use in the house.
Many times we modern people do not see the easy way because we are so used to machines.
Everyone should build a hornbow whit only a knife it can be done but it takes some time. What it gives is understanding for how the process makes the design. Well done and no tillering is needed, just brace and shoot
I have a picture of a bow without horn, just wood and sinew
the horn was glue in later.
http://198.170.107.188/phpBB2/files/inner13_245.jpg
I did read some Swed build a house from stoneage. They did use tractor to make the polehole, crane lifting the loggs and more. Because they was not strong enough to do it by hand. At the same time I was building a shelter for my machines the same way and did it alone by hand, simply inch by inch with a rope I lift the loggs. With two or more man the loggs could been much heavier then what they did use in the house.
Many times we modern people do not see the easy way because we are so used to machines.
Everyone should build a hornbow whit only a knife
it can be done but it takes some time. What it gives is understanding for how the process makes the design. Well done and no tillering is needed, just brace and shoot I have a picture of a bow without horn, just wood and sinew
the horn was glue in later.http://198.170.107.188/phpBB2/files/inner13_245.jpg
Last edited by Redhorse on Thu Feb 16, 2012 5:53 pm, edited 1 time in total.
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JR
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@Kviljo: Thank you!Kviljo wrote:I am very happy to finally see you here, JR! I'm certain that you will enjoy the good scientific atmosphere here, once the somewhat heated welcome has settled a little
Your method of first tillering the core and sinew before applying the horn seems to be a legit way of getting a proper tiller on designs that one does not know the limb taper of. I have used a similar method to understand the tiller of the norwegian two-wood bows in my masters thesis. My limited experience with horn bows tell me that there are some important technical advantages and historical evidence pointing to the "traditional" way of gluing the horn to the core before applying sinew....
I am not convinced of the good scientific atmosphere here, but this is not your mistake. 
I like your words "to understand the tiller". That is what I mean. Most of the people here want a fast, a strong, an efficient bow. And what about the beginners? I have written my chapter for beginners in 2008, I have to point it again. And I have to point to the fact that I have written that there are other methods of doing this (p. 215 middle), giving a lot of literature. Mr. Redhorse should read it again.
Today, when building a new type of bow I prefere "the other way": once, for the first time with this bow " to understand this bow". As an experienced bowyer I can later, for the second bow of this type, do it the traditional way, I agree to the advantages.
If a very experienced bowyer like Adam want to do it the traditional way by using best materials to get best performance and efficacy then he should do so and I am convinced, he can do. Not me, I need some forerun.
@Adam: No problem with your opinion, especially the first passage: That's it! And the rest: I have not built as many composits like you, but have done these experiences too.
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Justin Ma
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Something tells me you've never tried shooting with a heavy composite bow. It's quite a nice experience. You should try it.Patrick Menzies wrote:I guess the performance of your bow would have me saying it's a good question why the bothered switching to composites if they don't even perform as well as a wooden bow.
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Dusan
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JR. sorry for mi honesty ,you jumping like rabit around the true . 
Some questions. Whi novice - like you - in horbows -was " prime reconstructor" for museum ? Whi novice like you- (and everybody who gluet his first wood lamela vith piece of horn) writ "book" about hornows - ?
This is somthing very simmilar like Redhawk
Some questions. Whi novice - like you - in horbows -was " prime reconstructor" for museum ? Whi novice like you- (and everybody who gluet his first wood lamela vith piece of horn) writ "book" about hornows - ?This is somthing very simmilar like Redhawk
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Patrick Menzies
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- Location: Ontario
[quote="Justin Ma"][quote="Patrick Menzies"]I guess the performance of your bow would have me saying it's a good question why the bothered switching to composites if they don't even perform as well as a wooden bow.[/quote]
Something tells me you've never tried shooting with a heavy composite bow. It's quite a nice experience. You should try it.[/quote]
So I hear but we're talking about a precise replica of a supposed representative bow of the composite warbow type.
I keep hearing the praise but still looking for results.
All heavy bows are quite spectacular in a way.
Tell me about your "nice experience" and how it was better thasn anything else.
Something tells me you've never tried shooting with a heavy composite bow. It's quite a nice experience. You should try it.[/quote]
So I hear but we're talking about a precise replica of a supposed representative bow of the composite warbow type.
I keep hearing the praise but still looking for results.
All heavy bows are quite spectacular in a way.
Tell me about your "nice experience" and how it was better thasn anything else.
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Justin Ma
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Well, you're welcome to come to the Bay Area and I'll let you shoot with my 70# Grozer Biocomposite Turkish-short. That way you can judge for yourself how you like the speed and lack of hand shock of a bow which is almost like a horn bow (except that it's processed and glued differently).Patrick Menzies wrote:So I hear but we're talking about a precise replica of a supposed representative bow of the composite warbow type.
I keep hearing the praise but still looking for results.
All heavy bows are quite spectacular in a way.
Tell me about your "nice experience" and how it was better thasn anything else.
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Patrick Menzies
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PaleoNinja
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- Location: Berkeley, California
Hi Patrick,
http://www.atarn.org/islamic/Performanc ... h_bows.htm
This is an article Adam wrote, check footnote 18 for performance vs. yew longbows.
http://www.atarn.org/islamic/Performanc ... h_bows.htm
This is an article Adam wrote, check footnote 18 for performance vs. yew longbows.