Strength and Penetration of Scythian Bows
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Patrick Menzies
- Posts: 122
- Joined: Sun May 08, 2005 12:39 am
- Location: Ontario
Adam, I have always wondered why so many horn bows have horn way out to the ends , particularly the ones which have working hinges for the bending sections. The idea of using many sections of wood for the core never really made sense to me(except in a wood shortage situation). I have long been toying with the idea of making a one piece core composite with horn only on the bending section. My personal feeling is that the scythian bow wasn't strongly reflexed. The pictures of them being braced apparently indicate this. So my plan is a short elm recurve with a layer of horn lining the deflexed arches. Perhaps the bows were deflexed to allow easier stringing while actually on horseback. Pat
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Bede
- Posts: 2360
- Joined: Mon Mar 14, 2005 11:57 am
- Location: Sydney, Australia
Pat,
I have some thoughts for you that might help.
The Turkish bows I inspected in the Grayson Collection often had the horn scraped away from the upper ends of the kasan or ridged section. Even the grip was often thinned down. I assume that this was more to fit the hand than for anything else. The bow I shot at Utah, made by Harry Drake in the Turkish style, had the horn scraped away at both ends of the limbs. The grooves for the gluing of the horn to the core were still visible. This is true of original bows where the horn has been scraped away from the core at the kasan. The Omnogorov bow was built with the horn not reaching the ends of the ridged section. Adam may have a straight forward reason for these various approaches based on constructional needs.
Adam's experience also will better explain the sectional cores. I would not doubt that the Scythian bows had one piece of the core extending the full length. Bows like Stephen's Khotan bow with large grips may have started the two part construction with a diagonal splice at the grip. They also had applied wooden strips on the belly at each end to form the ears. Later Turkish, Persian and Chinese bows with their "V" splices seem to be a development of this. Possibly it was done for greater strength.
I have some thoughts for you that might help.
The Turkish bows I inspected in the Grayson Collection often had the horn scraped away from the upper ends of the kasan or ridged section. Even the grip was often thinned down. I assume that this was more to fit the hand than for anything else. The bow I shot at Utah, made by Harry Drake in the Turkish style, had the horn scraped away at both ends of the limbs. The grooves for the gluing of the horn to the core were still visible. This is true of original bows where the horn has been scraped away from the core at the kasan. The Omnogorov bow was built with the horn not reaching the ends of the ridged section. Adam may have a straight forward reason for these various approaches based on constructional needs.
Adam's experience also will better explain the sectional cores. I would not doubt that the Scythian bows had one piece of the core extending the full length. Bows like Stephen's Khotan bow with large grips may have started the two part construction with a diagonal splice at the grip. They also had applied wooden strips on the belly at each end to form the ears. Later Turkish, Persian and Chinese bows with their "V" splices seem to be a development of this. Possibly it was done for greater strength.
Bede
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Adam Karpowicz
- Posts: 753
- Joined: Sun Mar 13, 2005 11:57 am
- Location: Canada
Pat, your idea for a bow is sound. I think there was a shortage of not only wood, but also horn. So using horn in the bending section only makes sense. One thing to remember: the composite limbs can take a lot of bending. It means the deflex in the limbs could not be very great. I think the limbs were straight (or nearly straight) off the reflexed grip when the bow was made. The rest of the deflex is string follow. The layer of sinew would have to be rather thick, around 1/4".
Bede is correct, the horn in the kasan section should be thinner. In flight bows it may only reach to 1/2 of kasan and be very thin. I saw a disassembled bow where the horn layer was ending no more than 2" beyond sal. This is to make the limb ends as light as possible, since the wood alone is lighter than horn. Lighter limbs move faster.
I found there is a problem with the durability in this type of construction. There is a lot of shear/compression stress on the glue line betw. the horn and wood and the horn tends to delaminate if made too short. It may not matter for the short-lived flight bows, but durability would be important for the war bows. In bows where the horn is present (even if thinner) on the kasan section this problem does not arise.
Adam
Bede is correct, the horn in the kasan section should be thinner. In flight bows it may only reach to 1/2 of kasan and be very thin. I saw a disassembled bow where the horn layer was ending no more than 2" beyond sal. This is to make the limb ends as light as possible, since the wood alone is lighter than horn. Lighter limbs move faster.
I found there is a problem with the durability in this type of construction. There is a lot of shear/compression stress on the glue line betw. the horn and wood and the horn tends to delaminate if made too short. It may not matter for the short-lived flight bows, but durability would be important for the war bows. In bows where the horn is present (even if thinner) on the kasan section this problem does not arise.
Adam
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jack farrell
- Posts: 1864
- Joined: Sun Mar 13, 2005 3:40 am
- Location: Texas
Pat and all; On the different kinds of bows.... from Arab archery, 1500s.
"The hand bow is of three varieties: Hijazi Arab, composite and Persian, which is also Turkish. ... The bows of the Hijazi Arabs are also of three kinds: One is made from a single stave: another is made of a stave or two staves joined lengthwise: and the third is backed or reinforced.... The method is that of shaving the wood down. The reinforced bows are those which have the horns of goats placed in the belly and the sinew on the back...
The second variety of hand bow is the composite. It is composed of four different materials: wood, horn, sinew and glue....It is called composite because of the manner of its construction. It is also described as separated, because of the disconnected nature of its parts before they are put together.
The third variety of hand bows- the Persian and Turkish- are made in the same way as the Arab composite bow...."
"The hand bow is of three varieties: Hijazi Arab, composite and Persian, which is also Turkish. ... The bows of the Hijazi Arabs are also of three kinds: One is made from a single stave: another is made of a stave or two staves joined lengthwise: and the third is backed or reinforced.... The method is that of shaving the wood down. The reinforced bows are those which have the horns of goats placed in the belly and the sinew on the back...
The second variety of hand bow is the composite. It is composed of four different materials: wood, horn, sinew and glue....It is called composite because of the manner of its construction. It is also described as separated, because of the disconnected nature of its parts before they are put together.
The third variety of hand bows- the Persian and Turkish- are made in the same way as the Arab composite bow...."