Deconstructing Denniswood
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I still have a few pieces of that older wood left. Perhaps I should save them for another experiment.
Backwoods Savage said:
Yes, I think you are right.
I really think that somehow the ash split Tony gave me was not your wood. He said he was pretty sure it came from the stuff you had wrapped in bailing twine, but there was ash in that bin at Woodstock and your bundles were in there with them. Only thing I can think of. I've been saying for a couple years now that firewood stored outside in your general area won't ever get below about 16% MC, but it WILL get there... and in a lot less time than nine years.
If you want me to re-test some of that old stuff, I'd be only too happy to oblige you. You deserve a fair shake here after all you have contributed to this board. If subsequent splits test out the same, I guess we'll just have to accept it, but I'll feel better knowing that Denniswood is every bit as low in MC as we think it should be.
I admit it, I was tired of hearing about his nine year old splits, so I have been going out to his house every night and hosing down the firewood.
It was reported that the Progress was throwing prodigious amounts of heat. It's possible that the Ash was heavily perspired upon... :lol:Battenkiller said:
Jags said:
Well, of course it is! And it will pick up spilled grape juice... just at a crippled snail's pace.
What wood cannot do, no matter how long you leave it, is to pick up water from the air beyond the EMC. As you can see from this chart, in order for Sav's wood to regain enough moisture to show a MM reading of 28% MC on the inside, it would have to be stored in an environment that never dropped below about 96% relative humidity (that's with the species correction of three percentage points). If that moisture came in the form of rain, we should see the moisture gradient pointing in the other direction (i.e. wetter on the outside than the inside). That isn't what we saw. For Dennis' wood to reach 28% MC inside, the entire split would have to have gotten up to 28% MC (maybe 2-3 years at a constant 95% RH day and night) and then dried down to 15% on the outside.
But, no, that couldn't happen either, because as soon as a new moisture gradient was established, water on the very inside would begin to diffuse from the center and it would then be lower than the fiber saturation point of the wood (about 28%). And... AND..... AND...... because of a phenomenon called "hysteresis", once wood has dried down to a certain EMC, it will always rehydrate to a lower in MC at any given RH than it would have reached on the way down (hope that makes sense). The areas in gray on the chart represent the upper and lower hysteresis limits throughout the complete range of MCs.
![[Hearth.com] Deconstructing Denniswood](/talk/proxy.php?image=http%3A%2F%2Fimg.photobucket.com%2Falbums%2Fv306%2Fdrfera%2FForums%2FHoadleyEMCChart.jpg&hash=8c7d3b91be7f2cc09b223d0963974eef "[Hearth.com] Deconstructing Denniswood")
BTW this chart was copied from Dr. Bruce Hoadley's book, "Understanding Wood". Note the text I highlighted in light green. The most important thing in a 300 page book according to the author himself. I'm of the opinion that this chart is the most important thing to know about drying firewood as well. Once you grasp its true meaning, everything else will fall into place.
I'm confused, then. Not about the concept, but I just can't theorize a scenario that would explain the data you obtained from these splits. I'll pay for Denis to send some new stuff, because hat's all I can come up with. I thin that Dennis should find some really old wood, some mid range aged stuff, and some new stuff. We really need more points of data.
Dangit BK, now you've got me itching to experiment and my wife won't like how this will go. PS - I'm gonna rehydrate the wood in a pressure cooker, just because it sounds like fun. Not sure what i'll be proving with that, but it will be fun. Maybe it will show an increased rate at which splits RE dry after being rained on.
Edit: I apologize for the spelling mistakes. I've turned off autocorrect on the iPad, because it was frustrating me. Maybe I need to turn it back on.
Dangit BK, now you've got me itching to experiment and my wife won't like how this will go. PS - I'm gonna rehydrate the wood in a pressure cooker, just because it sounds like fun. Not sure what i'll be proving with that, but it will be fun. Maybe it will show an increased rate at which splits RE dry after being rained on.
Edit: I apologize for the spelling mistakes. I've turned off autocorrect on the iPad, because it was frustrating me. Maybe I need to turn it back on.
Danno77 said:
Well, Danno, try anything you want that sounds like fun to you...but I'd suggest being real careful to avoid irritating Mrs. Danno. I can't quite stretch my imagination around somehow equating a pressure cooker to getting rained on, but hey...carry on! Rick
Battenkiller said:
BK, the only ash that was there is the stuff I brought. I just don't know for sure which wood you got. If memory serves me I took some from 2009--2010, 2008-2009, 2007-2008, and the two splits from December 2002. It was all white ash with the exception of the one cherry that was from the 2002 batch.
Backwoods Savage said:
Then I'm gonna have to assume that I got a split from the 2010 batch. It's the only thing that makes sense. Maybe you should start branding the date on each split. ;-)
The stuff Tony sent me doesn't even look that old. The cherry OTOH looked old as the hills. It is pretty dense stuff, though, both of the splits. I think I'll go downstairs and light the first fire of the season with kindling left from that wood. Good way to kick off a new hearth year, with wood that's almost a decade old... air-dried by the master himself.
Let's see... 1/4 part SuperCedar, 4 parts Savash, 4 parts, Dennischerry, and a heaping dollop of last year's black birch on top. Sound like a good recipe for H-E-A-T?
Each bundle was marked as to the year it had been split. They were tied with baler twine; each year separate.
Are we about done here? A thread that runs to 4 pages and gradually deteriorates to sexual innuendo is, IMO, about done dancing. I'll leave it for a little while for comments, but if there's no compelling reason to leave it open, I'm going to shut it down. Rick
Rick, I spent a lot of time on this, both in the actual work done and in the write up, uploading photos, scanning charts, etc. I know that this stuff really isn't your cup of tea, but there are lots of folks here that find this interesting. It's also extremely useful for new burners who are being advised to use moisture meters and are not really understanding the pitfalls of using them, or exactly what they are showing you.
I can't control the posts others make, but to shut a thread down that I began in all sincerity to help the membership improve their wood processing is a bit beyond me as to why that would be necessary. A polite reminder to the offending posters that this is a family forum is all that is really necessary. Yes, I did have a lot to add here, but I was waiting for more critical and serious comments to come in. No point in my wasting any time thinking about this one any more if you're just going to arbitrarily shut it down.
I can't control the posts others make, but to shut a thread down that I began in all sincerity to help the membership improve their wood processing is a bit beyond me as to why that would be necessary. A polite reminder to the offending posters that this is a family forum is all that is really necessary. Yes, I did have a lot to add here, but I was waiting for more critical and serious comments to come in. No point in my wasting any time thinking about this one any more if you're just going to arbitrarily shut it down.
And BTW... over 1300 views and over 70 replies in less than 48 hours might suffice to show you the extent of the interest in this topic among the readership. Only a scant few replies contained any sort of sexual innuendo. Again, beyond this OP's control.
Battenkiller said:
Wrong, Bk...I'm as geeky a Mechanical Engineer as you'll find, and it's quite obvious that you've put a good deal of thought, time and effort into this. flatbedford was kind enough to remove the text of his post. Carry on, I'll let it run for now. Rick
Apologies for initial derailment, but my original thoughts still hold true. Wood is not a sponge has been thrown around quite a bit, but naysayers will be naysayers until someone like BK offers up hard data that wood was submerges, showered, pressure cooked, whatever, and then had it's MC checked again. Not that there haven't been labs that have been over this, but nothing like a fellow wood burned available to group discussion posting results from experiments that we can all replicate in our kitchens. And if I have to take a shower with a couple of splits of Black Walnut in the name of science, then so be it!
BTW, a lot of "initial post has been answered, so no more" going on around here lately. Disappointing, because of the comradery that is developed by joking, poking, and off topic banter that generally follows a successful post. It is what it is, and I'm just a guest here. Certainly not wanting to scare away new people with racey topics and comments, but a little isn't gonna hurt anybody, except people who have a financial interest in what goes on here.
BTW, a lot of "initial post has been answered, so no more" going on around here lately. Disappointing, because of the comradery that is developed by joking, poking, and off topic banter that generally follows a successful post. It is what it is, and I'm just a guest here. Certainly not wanting to scare away new people with racey topics and comments, but a little isn't gonna hurt anybody, except people who have a financial interest in what goes on here.
Joking aside, So what your saying BK is that air dried wood can only get as dry as the relative humidity of it's environment and the limitations of the species allow. Once that level is reached, even if submerged in water, the MC can only rise a relatively small amount, but never back to what it was when the wood was green. Does that mean that it's OK for me to continue not covering my stacks, as long as my wood has some time in the sun to allow surface moisture to evaporate before I attempt to burn it?
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