Author Topic: Return speed test (?)  (Read 17003 times)

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Offline son of massey

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Re: Return speed test (?)
« Reply #45 on: January 14, 2015, 01:10:32 pm »
I don't know that this is useless information. How much it is likely to impact a bowyer's actual decision making I don't know...I would bet as Pat suggested that people will use the staves they have regardless. But looking at return rate with given mass slats will give some information about the energy storage, I don't know that it is necessary to invoke harmonics. The more energy stored the faster the slat will overcome momentum and return to rest.

Also, while wood is not a completely homogenous material, trends within a species may be clear even after a relatively small sample size. I would not be shocked to hear that a certain species had values that were all pretty close to each other whereas other species may be incredibly inconsistent. Which are which may be of some value, and of the inconsistent samples did the better cases have anything in common-like late/early wood ratio?

Are there a lot of variables that may impact the results? Sure. Does that mean that trends will not show up or that people cannot look at the slat dimensions and make some educated guesses about how or why the slats behaved the way they did? Not really. I am interested to see what comes of this.

Huisme, are you planning on testing hop hornbeam? I would be curious to know how that stacks up against some of these other woods.

SOM

Offline Jim Davis

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Re: Return speed test (?)
« Reply #46 on: January 14, 2015, 01:24:58 pm »
I agree that there is useful information to be gained by the proposed tests.

But I think there are so many variables that unless they are all addressed few, if any, valid conclusions can be gained.

I would greatly like to see testing done with the care of a master's or doctoral thesis but written in a textbook tone.
Jim Davis

Kentucky--formerly Maine

Offline PatM

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Re: Return speed test (?)
« Reply #47 on: January 14, 2015, 02:01:34 pm »
Also I'd like to see 60 samples of each heat treated for varying lengths of time. That's 60 for each duration as well.  >:D

Offline Carson (CMB)

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Re: Return speed test (?)
« Reply #48 on: January 14, 2015, 02:30:13 pm »
I agree that there is useful information to be gained by the proposed tests.

But I think there are so many variables that unless they are all addressed few, if any, valid conclusions can be gained.

That about sums it up.
"The bow is the old first lyre,
the mono chord, the initial rune of fine art
The humanities grew out from archery as a flower from a seed
No sooner did the soft, sweet note of the bow-string charm the ear of genius than music was born, and from music came poetry and painting and..." Maurice Thompso

Offline son of massey

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Re: Return speed test (?)
« Reply #49 on: January 14, 2015, 03:52:42 pm »
To address some concerns with the variability thing it may be useful to have control experiments built in. Instead of going for same dimension slats, or same mass slats, or same width slats do same dimensions as well as same mass as well as same width...try a sample of each to see which of these different things actually makes much of a difference. It may add to the total number of experiments one needs to run, but it should help isolate which of the variables you need to control for and which are actually impacting results and which of them make essentially negligible differences. The absolute value of the return times will change from one set of conditions to another, but the relative return times if you rank different woods may not change much. If that were the case it would suggest that this is a more worthwhile thing to do as the results then appear to be more general behavioral things as opposed to engineering tricks or special case scenarios from slat to slat.

SOM