Metals406
Granfodder Runningsaw
Calculating Cord-Wood using the mathematical equation for the "Frustum of a cone" is very accurate; especially accurate when dealing with certain tree species.
Some of those trees being Engelmann Spruce, Tamarack, Western Larch, Ponderosa Pine, Lodgepole Pine, Sub-alpine Fir "piss fir", and some Grand Fir/Doug Fir. . . Any fairly evenly tapered tree will work. If the trees' taper is less consistent, measure smaller sections.
If you're getting a Firewood Permit from the FS, you might as well get a "Cord" of wood. There's 128 Cu. Ft. of wood in a Cord, unfortunately, you'll get air gaps in a stack 4'X4'X8' (or any 3 dimension combination). . . But that's the quickest way to figure out what you got stacked.
A FS Permit in these parts is $20.00 for 5 cords--and that's also the minimum amount you must purchase. I will also spend a lot of time and fuel hunting down the wood, thanks to the FS's affinity for locking every gate, and "Tank Trapping" roads. Then you have chains, guide bars, air filters, saw maintenance/ware and tare, files, fuel mix, fuel, and bar oil. . .
I want a Cord, when I write it down on the permit.
Here's all you have to memorize:
V= π (r1² + r2²) h/3
So lets break it down simple stupid. . .
I have a nice buckskin Larch I just dropped. Now I'll dream a little bit, and say it's 72" on the butt, 110' long, and 8" when I cut the top. Now let's enter real values in our formula:
V= 3.14 (pi) (1296 + 16) 110/3
Now solve to get Cu. In.~~~ 3.14 X 1312 X 110/3 = 151,054.9 Cu. In.
Now divide Cu. In. by 12³, and you get = 87.42 Cu. Ft. Or 68% of a Cord
It makes it way quicker to have a Construction Master, or scientific calculator on hand--but any calculator will do. . . Or you can do it all long hand.
If you're thinking, "That would take too much time and effort", I'd say not really. You measure two ends of your tree, and the calculation takes less than 1 minute with a calculator.
Once that same tree was split and stacked, you might come up with 95% of a cord? You just shorted yourself 27%.
I don't want to argue with anyone, that's not why I'm posting this. If you agree, great. . . If not, move forward and keep-on-keepin'-on.
Some of those trees being Engelmann Spruce, Tamarack, Western Larch, Ponderosa Pine, Lodgepole Pine, Sub-alpine Fir "piss fir", and some Grand Fir/Doug Fir. . . Any fairly evenly tapered tree will work. If the trees' taper is less consistent, measure smaller sections.
If you're getting a Firewood Permit from the FS, you might as well get a "Cord" of wood. There's 128 Cu. Ft. of wood in a Cord, unfortunately, you'll get air gaps in a stack 4'X4'X8' (or any 3 dimension combination). . . But that's the quickest way to figure out what you got stacked.
A FS Permit in these parts is $20.00 for 5 cords--and that's also the minimum amount you must purchase. I will also spend a lot of time and fuel hunting down the wood, thanks to the FS's affinity for locking every gate, and "Tank Trapping" roads. Then you have chains, guide bars, air filters, saw maintenance/ware and tare, files, fuel mix, fuel, and bar oil. . .
I want a Cord, when I write it down on the permit.
Here's all you have to memorize:
V= π (r1² + r2²) h/3
So lets break it down simple stupid. . .
I have a nice buckskin Larch I just dropped. Now I'll dream a little bit, and say it's 72" on the butt, 110' long, and 8" when I cut the top. Now let's enter real values in our formula:
V= 3.14 (pi) (1296 + 16) 110/3
Now solve to get Cu. In.~~~ 3.14 X 1312 X 110/3 = 151,054.9 Cu. In.
Now divide Cu. In. by 12³, and you get = 87.42 Cu. Ft. Or 68% of a Cord
It makes it way quicker to have a Construction Master, or scientific calculator on hand--but any calculator will do. . . Or you can do it all long hand.
If you're thinking, "That would take too much time and effort", I'd say not really. You measure two ends of your tree, and the calculation takes less than 1 minute with a calculator.
Once that same tree was split and stacked, you might come up with 95% of a cord? You just shorted yourself 27%.
I don't want to argue with anyone, that's not why I'm posting this. If you agree, great. . . If not, move forward and keep-on-keepin'-on.
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