Some nice old axe handles

FortyTwoBlades said:
If I'm remembering right it sits between shagbark and bitternut hickories in both categories.
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What is not calculated with the Modulus(elasticity and rupture) testes is just how far a piece of hickory will bend. It is just going until the hickory doesn't recover or extrapolating the numbers based on the load and how much it failed to rebound. Hickory will take a huge amount of set or failure to recover before it breaks. Which is why its not a great bow wood. It doesn't recover well. But it can be bent much further than Black locust before it actually breaks.
 
garry3 said:
What is not calculated with the Modulus(elasticity and rupture) testes is just how far a piece of hickory will bend. It is just going until the hickory doesn't recover or extrapolating the numbers based on the load and how much it failed to rebound. Hickory will take a huge amount of set or failure to recover before it breaks. Which is why its not a great bow wood. It doesn't recover well. But it can be bent much further than Black locust before it actually breaks.
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Any sources of data on that? Just curious. :)
 
FortyTwoBlades said:
Any sources of data on that? Just curious. :)
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Sure its right in the descriptions of the study you guys where looking at for modulus of elasticity and rupture .https://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/ch04.pdf

Modulus of Elasticity Elasticity implies that deformations produced by low stress are completely recoverable after loads are removed. When loaded to higher stress levels, plastic deformation or failure occurs. The three moduli of elasticity, which are denoted by EL, ER, and ET, respectively, are the elastic moduli along the longitudinal, radial, and tangential axes of wood. These moduli are usually obtained from compression tests; however, data for ER and ET are not extensive. Average values of ER and ET for samples from a few species are presented in Table 4–1 as ratios with EL; the Poisson’s ratios are shown in Table 4–2. The elastic ratios, as well as the elastic constants themselves, vary within and between species and with moisture content and specific gravity. The modulus of elasticity determined from bending, EL, rather than from an axial test, may be the only modulus of elasticity available for a species. Average EL values obtained from bending tests are given in Tables 4–3 to 4–5. Representative coefficients of variation of EL determined with bending tests for clear wood are reported in Table 4–6. As tabulated, EL includes an effect of shear deflection; EL from bending can be increased by 10% to remove this effect approximately.

Modulus of rupture—Reflects the maximum loadcarrying capacity of a member in bending and is proportional to maximum moment borne by the specimen. Modulus of rupture is an accepted criterion of strength, although it is not a true stress because the formula by which it is computed is valid only to the elastic limit.
 
FortyTwoBlades said:
That had specifically been what I was curious about.
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It can be as simple as cutting a couple of slivers of wood two or three inches long, trimming them to about the same size and bending them with your thumbs and fingers. I believe this can tell me a lot. You can gauge the effort or force very easy. See how they rebound or take a set and also how and when they fail.
 
Yup. Just didn't know if there was any data on the subject already available. :)
 
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