Bede, I think there must be something wrong with the program you?ve used to calculate the cross- section measurements. Otherwise this bow is a grave- good.
A bow-limb with such a cross- section does not bend as it should in a useful bow made of a single wooden stave and not at all as a lamination.
This "Scythian design" has usually been made as a lamination of several slats of wood(and sinew?) or wood/horn and sinew.
The glue-line of such a lamination amplifies the drawweight.
Andrew, I guess that the bone-plates are used for to keep the siyahs in line and to reinforce " weak spots" of a bow?s design.
The bending- capablities of bone could be reinforced by cooking it in a solution of vinegar.
I think siyahs/recurves had been invented at several places, it is somehow within the evolution of bows. I mean every bowyer comes to the point thinking over how could I "pimp my bow".
Michael
Sayas, who invented them?
-
redhawk
- Posts: 618
- Joined: Sun Mar 20, 2005 9:45 pm
- Location: GERMANY,Schopfheim
- Contact:
-
Bede
- Posts: 2360
- Joined: Mon Mar 14, 2005 11:57 am
- Location: Sydney, Australia
Michael,
The measurements were checked against Stephen's original measurements. The bow was very unusual, but more have been excavated. It seems that there was little bending possible in the middle third of the bow and the tips must have uncoiled to some extent. Modern Korean bows appear to be a much better design to get a long draw with a short bow.
There is a tradition in early composite bows to have thick rather than flat limbs. This was why the deflex was necessary in angular bows. David Betteridge's original calculations showed that Scythian bows had draw length to bow length ratios closer to self bows than composites. The setback handle made the design even less efficient.
However, they were popular for at least five hundred years. They must have had some advantages. perhaps they were pleasant to shoot or kept their cast longer.
When we originally looked at the archaeology, there had not been so many bows and sections of bows excavated, but with more evidence it seems that these bows were thick and stiff in the middle as we anticipated. The cross sections I have seen were a complete surprise.
The measurements were checked against Stephen's original measurements. The bow was very unusual, but more have been excavated. It seems that there was little bending possible in the middle third of the bow and the tips must have uncoiled to some extent. Modern Korean bows appear to be a much better design to get a long draw with a short bow.
There is a tradition in early composite bows to have thick rather than flat limbs. This was why the deflex was necessary in angular bows. David Betteridge's original calculations showed that Scythian bows had draw length to bow length ratios closer to self bows than composites. The setback handle made the design even less efficient.
However, they were popular for at least five hundred years. They must have had some advantages. perhaps they were pleasant to shoot or kept their cast longer.
When we originally looked at the archaeology, there had not been so many bows and sections of bows excavated, but with more evidence it seems that these bows were thick and stiff in the middle as we anticipated. The cross sections I have seen were a complete surprise.
Bede
-
redhawk
- Posts: 618
- Joined: Sun Mar 20, 2005 9:45 pm
- Location: GERMANY,Schopfheim
- Contact:
siyahs........
Bede, I?m going on in the resarch of the "Scythian bow design".
I know the cross- sections you?re talking about.
A cross- section of a well working bowlimb for a drawweight in the 45- 65lbs range can?t be bigger than 3-4 squarecentimeter due to the materials been used.
Last year I was ordered to make a reconstruction of a very asymetrical scythian hornbow based on an Antique Greek drawing. We?ve checked that this asymetrical design provoques a bow with bowlength/drawlength ratio very close to Turkish hornbows.
Even the force- deflexion graph is much close to other horn- composites.
Michael
I know the cross- sections you?re talking about.
A cross- section of a well working bowlimb for a drawweight in the 45- 65lbs range can?t be bigger than 3-4 squarecentimeter due to the materials been used.
Last year I was ordered to make a reconstruction of a very asymetrical scythian hornbow based on an Antique Greek drawing. We?ve checked that this asymetrical design provoques a bow with bowlength/drawlength ratio very close to Turkish hornbows.
Even the force- deflexion graph is much close to other horn- composites.
Michael
You do not have the required permissions to view the files attached to this post.
-
Bede
- Posts: 2360
- Joined: Mon Mar 14, 2005 11:57 am
- Location: Sydney, Australia
Michael,
There are unfortunately many variables in the draw length calculations when you are basing your reconstructions on a few literary references and artists' representations. Betteridge came to the conclusion that Scythian bows were not very reflexed in construction and in other ways did not behave like efficient composite bows. However, he was convinced that they performed well within their capacities.
Incidentally, I meant "you" generally when I used it above. If I make a Scythian bow, I may say 'we". I am not criticizing your ideas. With Turkish bows and others where there is a lot of knowledge and artifacts, it is easier to be sure what to expect. However, the work you are doing with Scythian bows is pioneering so you may find out things that no one has known for the last 2,000 years.
There are unfortunately many variables in the draw length calculations when you are basing your reconstructions on a few literary references and artists' representations. Betteridge came to the conclusion that Scythian bows were not very reflexed in construction and in other ways did not behave like efficient composite bows. However, he was convinced that they performed well within their capacities.
Incidentally, I meant "you" generally when I used it above. If I make a Scythian bow, I may say 'we". I am not criticizing your ideas. With Turkish bows and others where there is a lot of knowledge and artifacts, it is easier to be sure what to expect. However, the work you are doing with Scythian bows is pioneering so you may find out things that no one has known for the last 2,000 years.
Bede