Bow ear materials?

pcoutin · Post by **pcoutin** » Mon Feb 01, 2016 8:16 am

I wonder what'd be a good way to make ears/siyahs out of bamboo? Jia Zhiwei appears to make them out of bamboo. Maybe just glue two fat pieces together on the sides? I wonder which woods have the best breaking-force/density ratio... or if it differs a lot for tension/compression when not bending. that is, which woods would result in the lightest ears?

Are tension failures due to shearing parallel to the grain? Do they matter for stiff ears more than compression failures? Would it be best to have different woods for tension and compression with static ears?

Bamboo, hickory, ash, douglas fir, juniper... would any of them make significantly lighter ears than the others?

Would curved ears take more strain than straight ones, akin to an arch? Though I think Adam Karpowicz wrote straight ones are lighter and more efficient for the same reason a straight path is shorter.

Pat Menzies · Post by **Pat Menzies** » Sat Feb 06, 2016 2:08 am

Bamboo in general is heavier than wood. People overthink the light ears/material thing.
The same way that bows of all materials end up weighing about the same, so do siyahs of different materials.

KenH · Post by **KenH** » Wed Feb 24, 2016 12:29 pm

Your questions about wood properties can probably be answered in the online Wood Handbook, which has LOTS of information. The grain structure of bamboo wold make me leery of using it in siyahs -- it is such straight grain and siyahs are subject to tranverse strain, that I would fear it would have a tendancy to split.