Main Discussion Area > Bows
Benefits of a lenticular crossection for white wood bows?
RyanY:
I think this is likely difficult to determine and more than likely a matter of doing what works with what we’ve got. I don’t think a flat versus rounded belly makes enough of a practical difference for bowyers to notice and choose one over the other from both a performance and safety factor. I can’t say with certainty but it seems our knowledge of engineering and physics helped us understand that relationship more than discovery from trial and error in bows. As with evolution, if it works good enough it survives. Doesn’t have to mean that it is necessarily the best.
Kidder:
We should also remember that we are talking about a relatively small sample size - we probably have a few hundred (?) surviving examples (many of which are only partial examples) over a period of thousands of years where we have to assume that probably millions of examples were made by many thousands of bowyers. To take a single or even a few similar examples from a specific time period and location and extrapolate that to conclude that “bows of this period, or that location were ————“ is probably beyond what can actually be said. I think the only safe conclusion is where environmental limitations necessitated a particular design ie cable backed bows by the Inuit.
Del the cat:
Just a couple of thoughts...
'Flat' doesn't occur very often in nature ( although, some rocks cleave flat and Ice is pretty flat) , and you tend to need something flat to create another flat surface. I suggest the curve is simply a more natural shape resulting from the working practices.
from a technical stand point, I think a flat belly tends to become slightly concave as it is bent and concentrates stress on the edges?
Del
Aksel:
--- Quote from: Hamish on March 27, 2024, 06:29:03 pm ---Hey Aksel, I don't doubt there are paleolithic bows out there with really flat bellies, It would just be harder to make them flat, vs lenticular, especially with stone, or bone tools
The cross sections that you show are lenticular in the working portion of the limb(wide), one is flat on the narrow non working or barely working portion.
That makes sense to me as very little tillering needs to be done on the levers, once you have initially roughed in the intended dimensions . The width is very narrow here, so it matters less if its flat or rounded, as its not as difficult to get the intended result. The wide working portion is a different matter.
The lenticular cross section lessens the chance of twist, as the centre of the belly acts as a keel. Over a 2" wide working limb, it still acts as virtually flat, without the difficulty of achieving a perfectly flat belly. Even though the bellies on these bows are not truly flat, I've always seen them referred to as flatbows.
The concept of flatness, or straightness, especially in pre modern times was relative. Design was organic, with no dimensions other than hands, finger widths, spans etc. If it achieved the desired result, with less work, then that's likely to be more common.
--- End quote ---
I agree that it might be harder to make a flat surface than a rounded with stone/bone tools. But I have made one elm bow with stone/bone tools and I managed to make the belly flat without much effort (especially since I am not a flintknapper, only with broken up flint stone). I also think modern people tend to under estimate the skill of the people of olden days. Also is the way we value/measure time completely different to theirs. But sure it make sense what you´re saying, although I don´t think (in general) they would take the "lazy" time saving route before the better more time consuming one and compromise with performance. But that´s only my feeling. Nice though to think about it and hear everybodys thoughts on this.
Aksel:
--- Quote from: willie on March 27, 2024, 07:08:36 pm ---
--- Quote from: Aksel on March 26, 2024, 06:14:40 pm --- I always like to think about,
--- End quote ---
and in the Americas, rectangular cross sections developed in similar cultures, but maybe after contact with metal tools?
the sudbury, of course might represent a more "traditional" NA design
it would be interesting to see if there are any surviving examples of pre-migration Asian bows
--- End quote ---
Yes, I´d be interesting to find this out
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version