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DRP
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# Posted: 18 Feb 2025 04:50pm - Edited by: DRP
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It takes about 1000 btus per pound to vaporize water.
There are around 8500 btu's per pound of dry (0%) wood.
Hmm try it with a pound of say 50%mc wood
1/1.5=.666 lbs of dry wood x 8500 btus=5666.6 btus available.
1-.66=.34 lbs of water x 1000= 340 btu's to vaporize the water.
5666 btus available - 340 tied up flashing off water =5326 btus heat.
The big thing we feel is it is hard to get the stove above steam heat initially until the water is gone. Once you have a good hot coal bed it doesn't hurt as much to throw on some green wood as trying to get some heat going with green wood.
I forgot to mention why the thermometer was in my pics. I knew the wood was cool and there would be a temp correction to the meter reading. For ~50F the correction was ~2% and when I let the wood warm up and checked it again it read 3% above the original reading. Not huge but another factor. At zero F the correction would have been +6 degrees, so it does get pretty far off as extremes. Likewise at 120 a 12% meter reading would actually be -3%, 9% mc wood. Just stuff to keep in mind as you meter away from room temp.
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paulz
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# Posted: 19 Feb 2025 07:52am - Edited by: paulz
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Quoting: DRP The big thing we feel is it is hard to get the stove above steam heat initially until the water is gone. Once you have a good hot coal bed it doesn't hurt as much to throw on some green wood as trying to get some heat going with green wood
Yes! Lighting a days cold stove takes dry kindling. I have a stack of old fence boards I split into half inch pieces, along with the used paper plates we eat off of. Then add aged branches until a nice red bed of coals. After that just about anything thrown on will burn. Here’s one of the wettish pieces I just threw on, it will go just fine in a bit.
In fact it can have an advantage. If a dry night log is put on before bed, it will roast the place for a few hours, then cold in the morning. A wetter log will burn more slowly and keep going until morning with a nice even temp.
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gcrank1
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# Posted: 19 Feb 2025 10:23am
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The joys of learning how to keep your fire stoked 
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paulz
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# Posted: 19 Feb 2025 11:12am
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See what you’re missing not having a wood stove at the new place?
At least I don’t have to think about the LP heater dying out. I did run the Williams the other day to make sure it still ran, in case I run out of 10 acres of wood.
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DRP
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# Posted: 19 Feb 2025 11:17am - Edited by: DRP
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Since we're talking about it...and its snowing again.. more meter trivia.
The main thing I use the meter for is to check the condition of wood in relation to the environment it will go into. Shrinkage and the warps (bow, twist, cup and crook) are all a result of moisture content change. Whenever possible and especially with finish materials we try to match the moisture content with what it will be in service. When the wood is no longer drying to the environment nor adsorbing moisture from it, it is considered to be at "equilibrium moisture content" with its surroundings. Obviously the surroundings are always changing in temp and humidity, so wood is always trying to reach emc. But it does work. Look at the table posted and the thermometer/hygrometer and meter readings... mighty close. The table is from chapter 4 of the "Wood Handbook" from the USFPL;
https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr190/chapter_04.pdf
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paulz
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# Posted: 19 Feb 2025 12:33pm
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Supposed to be rain over here but just went out to take this photo and a brief shower going on.
I built my deck out of logs I milled here, some I cut the trees down to build the road, others were already lying around. Here is one edge today, obviously was a straight cut back when (didn’t drink That much!). Why that one shrank so much I don’t know, freshly cut?
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DRP
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# Posted: 19 Feb 2025 02:38pm - Edited by: DRP
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It is from green wood drying, but also from a certain green wood drying. Take a look at the pic below.
Normal, mature, easy living cells, have the microfibrils that make up the S2 layer(the thick part of the cell wall) running vertical, with the length of the cell.
"Reaction wood", whether it is juvenile wood from the first ~25 yrs of tree growth, compression or tension wood in response to a lean, or root or branch wood, has microfibrils making up the cell wall on a bias to the axis of the cell. If you've ever messed with cloth, bias weave orientation is more flexible.
Shrinkage is moisture leaving those microfibrils and them moving closer together. If they are normal the wood shrinks in thickness and width but not length. If the "MFA" microfibril angle, is at an angle to the length of the stick and those fibers get closer together... the board gets shorter as it dries. I've had it break screws when deck boards shrink in length.
That board contained a lot of reaction wood, I'll venture a cleaned up end pic will show it is near the juvenile core. It seems to have shortened uniformly.
Many warps in drying are a result of unbalanced reaction wood in the stick.
If there is reaction wood along one edge and not the opposite edge, then the board will crook (hockey stick) as it dries. If it is on one face and not the other the board will bow (boat side).
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DRP
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# Posted: 19 Feb 2025 03:29pm - Edited by: DRP
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Juvenile wood is one type of reaction wood.
In order to right themselves softwoods put on compression wood on the underside of a lean and try to buttress under the load, that unique cell structure in the sketch above is infilled with lignin, the cement of wood and is unusually stiff but because of the bias MFA it breaks weak and unpredictably. Its that dull peanut butter looking grain on the board in the middle pic, hey that was a southern pine log home job, we're ot. The biology takeaway, softwoods prop up leans.
Hardwoods throw a strap over the top of the lean and pull... hardwoods make tension wood. Somewhere they took 2 different paths to solve the same problem. There's a pic below of normal wood and tension wood with the central G, gelatinous, layer hanging out. That is the kevlar winch cable. If you are a woodworker and have had a hardwood board that could not be sanded smooth, it was always kind of fuzzy. That is those rubbery G fibers. I've been told thst Native Americans would gather bow stock from ridgetops where the windblown trees are. The takeaway, hardwoods throw a cable over and pull leans.
I also dug up some pics of compression wood. That deck board sheared 2 rows of screws and will lay back down flat after a long wet spell. One of these days I'll make her happy but I think it is cool to watch it shrink and curl, wet and lay down 
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gcrank1
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# Posted: 19 Feb 2025 05:01pm
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Nice ski ya got going there
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