Black locust

[Jim Davis]

...

Asharrrow, I did not know that, or had forgotten it.  Thanks.  That would change the hardness and crush strengths a LOT, along with everything else.  I'm shocked that the US government data base folks couldn't get their hands on a dry sample, when they have so many woods from all over the world.

Oh. I'm  sure they had dry samples, did the tests, then LOST the results before they could be entered in the database. It's ironic that the wood we would most want to see numbers for is the one they don't have. There are some hacks there now who are less interested in the science of wood than in making a pretty website. One of them told me some years ago that the numbers for dry Osage wouldn't be much different from those for green Osage! A dolt, I think.

[Springbuck]

"One of them told me some years ago that the numbers for dry Osage wouldn't be much different from those for green Osage!"

Yeah, I ain't buyin' it either.....

[MulchMaker]

So if we don't have good numbers for Osage do we have good numbers for yew or are we comparing because of similar kind of tree?

[Springbuck]

I was comparing them because they are both commonly used, fairly heavy, and are often treated much the same, being on the upper end for wood strengths and density, at least for native North American hardwoods.

The website has specs on a ton of woods, and I always assumed their testing was somewhat standardized.  They measure what it takes to bend a bunch of samples, what it takes to break a bunch of samples, physical weight per cubic foot, side hardness, longitudinal crushing resistance, specific gravity, etc... they even rate woods for different applications if you search for spmething like "bows" or "eating utensils" or "tool handles", but they don't cover everything, and some of their conclusions, esp about bow woods are suspect to me, as if they were done from behind a desk, you know?

But, if the testing isn't careful and standardized, then it's all partially out the window at least.

http://www.wood-database.com/    they do have specs on yew.

[Jim Davis]

It's my understanding that the Wood Data Base ( http://www.wood-database.com/  ) has only copied the data from the Forest Products Laboratories https://www.fpl.fs.fed.us/research/centers/woodanatomy/index.php which did it's testing beginning in the 1930s. I like to see credit given to the agency that did the work.

FPL did test many samples of each variety of wood with a high degree of scientific diligence. WDB is just capitalizing on FPL's work.

Bookmark https://www.fpl.fs.fed.us/research/centers/woodanatomy/index.php

Jim Davis

[MulchMaker]

This is a lot of info to process. Lol, newbie experience is probably the reason. I guess im trying to wrap my head around the uses for these numbers. So a heavy wood like black locust or Osage is more Versatel than say a lighter wood like chokecherry. Is that what the numbers are for?  I won't use the term better because I'm guessing that has a lot of different variables on why one chose the  particular wood in the first place. Although I am still new every time some one asks "what is the best bow wood in my area" the smart Alec in me always wants to reply "the one that is most abundant that you can identify that will make a bow" for me that is 1 black locust 2 buckthorn 3 chokecherry 4 hickory. I'm glad I got one at least with a heavy numbers. I'll have to look up the other woods I have close by, I'm guessing the other numbers have a lot to do with design as well.

[Springbuck]

Jim, that's the site I used to use, and they did have more extensive write-ups.  Good catch.

[Jim Davis]

... Although I am still new every time some one asks "what is the best bow wood in my area" the smart Alec in me always wants to reply "the one that is most abundant that you can identify that will make a bow" for me that is 1 black locust 2 buckthorn 3 chokecherry 4 hickory. I'm glad I got one at least with a heavy numbers. I'll have to look up the other woods I have close by, I'm guessing the other numbers have a lot to do with design as well.

MM, your last sentence tells the whole story as related to the mechanical properties of wood. The numbers tell us how to design the bow. Stiffer wood can be thinner and or narrower. Woods that have a high WML (work to maximum load) number can be thicker. Wood that is denser can also be thinner and or narrower.

The properties work together so that, for instance, a wood that has high WML but is not as stiff will have to be wider than a bow that has a lower WML but higher modulus of elasticity.

We are better off learning what designs have worked with a given wood and follow that  example. After making a few bows, then the numbers can start to be  useful in planning a different design or a modification.

I think only a mechanical engineer would start out with the numbers and design a bow. But don't turn up you nose at the engineers. Paul Kolpsteg was one and contributed mightily to the sport as well as being a bowhunter.

From my time poring over the numbers, of American woods, I would rate them from best, Osage, Yew, cherry bark oak, hickory (pig nut, mockernut, and shagbark in that order), black locust, persimmon and downhill from there.

Jim Davis

[Springbuck]

"I think only a mechanical engineer would start out with the numbers and design a bow."

  I started doing this, poring over numbers, while at work on the night shift, while the ER was quiet, etc.  Then I would see some numbers I liked and go get a piece.  Then I'd say, this stuff is stiff and dense, but elastic and I'll back it with bamboo.  So, I'd do it.  Then I'd work it and say to myself, this stuff acts kinda like, "X" other wood, so maybe next time I'll.......

So, I found a few nice tropicals that were pretty and worked with a backing, etc........ Otherwise, I agree with your list pretty much completely, and it's nice to find out a lot of woods (like white woods as a whole) act pretty much the same, and need only  minor changes that can be made during construction and tiller.

[MulchMaker]

At this stage of the learning curve I think I'll play it safe and keep it simple. I think since I have a lot of locust I'll stick with that and make a few bows before I start working others. The beauty about this wonderful hobby is that I can collect wood I wanna try later any time. The first goal is to be successful the second is to improve my work. I figure I've got some at least 2-3 bows to break if not 30 before I get a shooter. I may able to lessen the breaking if I don't  drastically change my material every time. Wood has differences between trees, changing the type of tree will make the difference to different. Thanks for the help, and for helping me select a path.