the only reason you only burn 3 cords is because you live in a subdivision with all them houses around you to block the wind nate. besides your house aint to big either.
I Burn About 3 ft3 Per Day
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fossil said:
First thing then, all those BTU tables for various species/cord need to be tossed, eh? :-/
Battenkiller said:
No, of course not, BK...but they're all based on some assumed density. And they must have made some assumption about the average airspace in a stacked cord...or come up with an average weight of a cord. They would serve the purpose at hand quite well with a simple conversion to weight, because we can easily measure that. Since we don't have an easy means of determining volume to any degree of accuracy, I guess we have to start with weight and MC, and go from there. Or, we could simply load up our stoves, get some nice fires going, and read a good book about something totally unrelated. Rick
ETA: Put simply, no two cords of the same wood, processed and stacked by the same person, will ever be of exactly equal weight (barring complete coincidence). So, BTU/cord (or any other expression of volume) is an average approximation, at best…as is any measure derived from it. BTU/lb is a more meaningful and useful parameter.
I am always fascinated by a few of our folks that try to make a science out of burning pieces of very large weeds in a metal box to heat their caves. :lol: You talk about an endeavor with a lot of Kentucky windage, wood burning is it.
The reason people started burning gas and oil and invented thermostats in the first place.
The reason people started burning gas and oil and invented thermostats in the first place.
fossil said:
But just how do we determine the MC? With the "two to three years stacked until it's below 20% MC" method? Well, Savage's wood only got to 28% on the inside that way, while wood in your locale would be drier than Aunt Tilley's backside. And moisture meters are only just so good. They work best when the wood is drier than most folks can get it (lower than 14%), and only if corrected properly for species, and they are next to useless above 40% MC dry-basis. The oven-dry method is right on the money, but it is tedious and has to be done carefully with an accurate scale that reads in the correct range for the samples you are weighing, and the procedure requires decent lab technique. Any easier method's I'm missing?
The beautiful thing about using volume is that you eliminate the need for accurate MC measurement. If you know your species, you know roughly how much dry wood fiber by weight should be contained in any given volume. Yes, it is just an approximation gotten from averaging lumber industry data from all over the country, but it is a lot easier to use than it is to weigh an entire cord and oven-dry it to determine the MC. Volume doesn't change much from green to dry, but weight changes dramatically. That's where all those wacky tables that show how much heat is lost by burning green wood come from. That heat isn't lost... it was never there to begin with. Last I tried, water doesn't burn for s***, so including it as a "lost" component of a split that always contains the same amount of wood fiber at all MCs is misleading at best.
Volume in cord wood will always be an approximation. The published BTU tables use industry established volumetric averages, calculations similar to the ones I showed, and call it a day. But without a doubt, if a guy stacks his wood tightly after it is fully seasoned he will get a lot more heat out of his cord than another guy stacking the same wood loosely when it is green. What does this mean in practical terms?
Time to pour another two fingers and toss in another couple splits.
NextEndeavor
Burning Hunk
What started out as a simple question of volume (an amount my pickup holds and for many who purchase wood fuel or that amount used in a day) turned into analysis paralysis .... made my head hurt. Think I'll coin an earlier quote about tossing large weeds in a metal box to heat our cave and leave it at that. I do this for recreation!
BlankBlankBlank
Minister of Fire
Or invest in a large water tank. Add a specific volume of water. Lift your cord of wood with a hoist, lower into tank, and measure displacement. Do this for each of your cords. Now you'll know the exact volume of wood in each cord.
Next re-dry all your wood.
Next re-dry all your wood.
WoodNStuff said:
Well, actually, no you won't, unless you somehow force the wood to completely submerge...otherwise it's gonna float. You'll know the weight of the wood, if you catch and weigh the displaced water (the two weights will be the same), but you'll only be able to measure (from the volume of water displaced) the volume of the wood beneath the waterline when the wood comes to rest floating in the water. If you were to somehow forcibly submerge the wood completely into the water and then measure the volume of the displaced water, you'd know the volume of the wood. Rick
BlankBlankBlank
Minister of Fire
fossil said:
While possible and accurate if done correctly, impractical and in jest. Another two fingers and toss on a couple more splits kind of guy here.
BrotherBart said:
And this fascination is exactly why we are all here. And all our ancestors came from Kentucky anyway didn't they?
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