Primitive Archer
Main Discussion Area => Arrows => Topic started by: DavidV on December 31, 2012, 06:34:42 pm
-
I posted a similar chart on the Bows section and it got me thinking... Modulus of elasticity should vary directly with spine. So I made this chart with all the same information but with several more wood species and just about every softwood. Will need to add more exotics but that gets difficult. I'm not sure just how useful this is as far as spine goes but I can see weight being important when trying new woods.
-
David, I recall being as industrious as you are when I was younger. You have done a lot of work on a concept I might have tackled if I had known how to use Excell.
I like both your charts VERY much. I sorted the arrow chart for specific gravity with largest first. If you do that and drop down to .45 SG, then look only at woods that have a MOE above 1,340,000 or so, there is a looooong list of good arrow woods. I had noticed before that black spruce should give Sitka spruce a run for its money.
The only discouraging thing is that lots of those woods are not marketed as such--might just be called "fir" or "spruce" without further identification.
Also discouraging is that where red and black spruce are harvested and milled, the logs are just slabbed off to be square and the best arrow wood--the outer slabs--is just chipped up for biomass or some other ignominious use.
When I lived in Maine, i could now and then get such slabs from a mill near me. I still have a few slabs of red pine (Pinus resinosa), but here in W. Kentucky, the only softwoods are loblolly pine (pretty heavy) and ERC (pretty floppy).
Thanks for making that chart. I have saved a copy and will guard it carefully.
Jim Davis
-
Thanks Jim, I enjoy the work honestly...especially wih Led Zeppelin playin' in the background ;)
I'd like to contact some of the big name shaft producers and see what the common spines are for given diameters and add the information to the chart. Then I could make a ratio of MOE to spine and try to predict a basic range of spines for woods that aren't commonly used. Of course the problem arises with old vs. new growth wood and early to late growth ratio.
-
David, hope I'm not taking too much liberty with your work, but here is a screen shot of the way I winnowed your more comprehensive chart to include my personal interests.
I deleted most of the hardwoods on the grounds of their being heavier than I would use. I also deleted any woods that didn't seem to be native species. I then sorted by modulus of elasticity and kept the range between the heaviest used commercially for shafts--Douglass Fir-- and the weakest commercially used for shafts--lodgepole pine.
I was pleased to find a total of 23 varieties of wood that should make good shafts.
Of special interest to me was the fact that black, red, and Sitka spruce are about equal, with any edge actually going to black and red. I am sure that the reason we don't see black and red spruce being marketed in shaft form is that Sitka is a much larger tree and it is easy to get it in clear lumber form. But those of us who live in the northern U.S. and Canada probably have access to at least one of those three spruces.
Here is my sliced and diced chart as a jpg.
Jim
-
Jim we may be on to something :) I'm emailing some of the big shaft producers, trying to see if the data correlates with their experiences.
-
I fear the BIG shaft companies will have little interest in trying woods other than those regularly marketed by one seller or another. And, after all, they are in business to make money, not do research.
But one way or another, a lot of us can use the above data if we make our own shafts. I'm stuck with what I can find at the big boxes, the lumber yards and occasionally some salvaged wood. I have found good spruce lumber, Douglas fir and yellow pine at Lowes. Western Kentucky is not spruce land.
Jim
-
I've used Black Spruce many times for arrows, it works quite well. The only problem is that it tends to grow in a spiral and has interlocking grain so it must be sawn not split. It also bad for warping while drying. I have a nice log of it tucked away that has been drying for about 10 years.
-
I've used Black Spruce many times for arrows, it works quite well. The only problem is that it tends to grow in a spiral and has interlocking grain so it must be sawn not split. It also bad for warping while drying. I have a nice log of it tucked away that has been drying for about 10 years.
Glad to hear you have used black spruce, Marc. I guess some care would be in order in choosing the tree. I used to have access to slabs at a small saw mll, but I also cut a few trees to get spruce arrow wood.
Jim
-
If you have BS shafts, or raw blanks, lying about for awhile they will warp on you but once the arrow is made and sealed they seem to stay pretty straight. I still have some raw blanks kicking around somewhere. I switched to Black Ash many years ago because I found that it was a much more stable wood and made stronger arrows. Black Spruce fails explosively when bent a bit too much. A wood that works easily and makes good arrows is Balsam Fir. With a SG of about .35 it's a light wood so arrows come out a bit on the light side but the wood splits easily and a seasoned piece is quite stable.
P.S. The numbers for Balsam Fir in the chart above do not match what I have on my Woods of the World disk
-
Here are the Forest Products Laboratories numbers:
-
Here are the Forest Products Laboratories numbers:
No not the same. There are 2 species of Balsam Fir in NA and both of have the same SG of .35 dry. I have cut a lot of Balsam and the wood is very light so I tend to go with what my disk says. Also I have cut a lot of Black Spruce and it is considerably heavier than Balsam and it's SG is .41 so it's just not possible that Balsam has the same SG.
-
Marc, I do know of at least one oversight in the FPL data, so they are not beyond making a mistake.
I have however found confusion among dry specific gravity and green specific gravity in various sources.
I too have cut lots of balsam fir--in Maine--and it did seem lighter than spruce, certaily softer too--. That was Abies balsamea. I know there are other firs commonly called balsam fir. Abies balsameais what the FPL data above is reporting.
I guess the chart DavidV made and that I slashed down to what I liked would be more useful if they included the latin names.
Jim
-
Jim
The species listed in my WOW disk are Abies Balsamea and Abies Lasiocarpa The first is an Eastern species while the second grows in the Western US and Canada. Regardless they both have the same SG listed.
-
Marc, does your Woods of the World disk tell what original sources were used? I have done quite a search online trying to contact Tree Talk inc. All the phone numbers I have found are no longer in service--even the fax number. I know that the disk production was directed by one Dr. Charles K. Baah, but I can find no trace of him either.
That's why I am asking if the disk lists its sources. Tree Talk Inc. seems to have blown away like a leaf in October.
Jim
-
Finally found this interesting record of shenanigans among the Tree Talk Inc. principles that resulted in a lawsuit for copyright infringement.
http://www.leagle.com/xmlResult.aspx?xmldoc=2002842190FSupp2d652_1778.xml&docbase=CSLWAR2-1986-2006 (http://www.leagle.com/xmlResult.aspx?xmldoc=2002842190FSupp2d652_1778.xml&docbase=CSLWAR2-1986-2006)
Here is what I think is a pertinent paragraph:
"In 1993 [Richard] Miller began work on WOW, a searchable electronic database on the world's commercial wood species. The database was designed to serve as a reference source for purchasers of wood and wood products. Along with a handful of hired students Miller gathered information on wood species from the public domain and published sources, including books, periodicals, magazines, and other websites, and incorporated this data into WOW"
Since the material was taken from existing data and by gatherers of unknown diligence, I conclude that any disparity between the WOW material and an original source leaves the WOW material at fault--and possibly both sources. At any rate, no testing was done for and no new testing reported in WOW.
Jim