Foolproof Moisture Content Assessment

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I almost started to give this experiment a try, but....then decided to head out and get another cord of wood cut and split instead....seemed like it might take me just as long......Ha! Cheers!
 
Battenkiller said:
Before joining up here, I just thumped on my chest and tossed another log of green oak on the fire. Who cares about secondary burns... I don't really think I get them in my stove anyway, and I couldn't see them if I did.

All the thermometers and moisture meters etc would be fun for me, but honestly- it won't really change the way I do things. I burn dry wood reasonably hot and efficiently the way I'm doing it- as evidenced by my liner and the heat I get. I care about secondary burns- reburning smoke is efficient as heck- I like that. That is a good design feature for the way I do it.

I had a compost thermometer before I broke it- was fun to see how hot I could get my compost pile. 165F was about my tops. Composted woodchucks, deer remains after I butchered it, etc at those temps. Good fun- but I still compost without the thermo.
 
FLINT said:
Battenkiller said:
The wet looking spots on this hickory slice are actually sugars that have boiled out of the end grain and dried there. Has anyone ever tasted the sap that exudes from wet hickory splits? Yummy! Too bad no one taps these things for syrup.


Actually, they do - here check it out - tulip poplar as well,

http://www.lehmans.com/store/Kitchen___Pantry___Poplar_and_Hickory_Syrup___phsyrup?Args=

Nope. Those are sugar syrups flavored with some kind of extract from the bark. Maybe they're delicious, don't know, but they're not made from sap.
 
gyrfalcon said:
Nope. Those are sugar syrups flavored with some kind of extract from the bark. Maybe they're delicious, don't know, but they're not made from sap.

Right. There is some old guy out in Indiana that has made a commercial hickory extract syrup operation. He gets loggers and farmers and such to gather shagbark that has shed from the trees, boils it with sugar, and then cooks it down just like maple syrup. It's all the rage now among chefs from what I've read.

I'll just keep licking the ends of the splits. It's very tasty stuff. My wife thinks it's gross, but maybe she's referring to the green warts on my tongue.
 
Don't say you weren't warned...
 
Smokey said:
Where do I find a micro-wave big enough to do a cord of wood at a time?
LOL!
 
You don't need to do a whole cord at once. Just bring in a day's supply, cut it all up into thin slices and MW them a couple at a time. Shouldn't take you more than five or six hours tops to get a day's worth ready. Besides, it's so powerful you only need about a couple splits worth to keep the stove cranking for at least 8 hours. ;-P
 
What you really need is a convection microwave so both parts of the experiment can be completed at once ;-)

Cool experiment, but I agree with others that it should be redone to see how accurate the MM are. Then one could factor in the proper amount of variance to make your MM readings accurate. I can only imagine the lively turn the conversation would take if I told Mrs. 'bert that I want to put some firewood in her microwave.
 
Sounds like something to do at the office after hours to me... "don't try this at home folks!" heh.

I really would rather like to have seen comparisons of the readings from cheap HF moisture meters (more than one model would have been best). However, I do like the overall experiment.
 
Slow1 said:
Sounds like something to do at the office after hours to me... "don't try this at home folks!" heh.

I really would rather like to have seen comparisons of the readings from cheap HF moisture meters (more than one model would have been best). However, I do like the overall experiment.

A few folks here seem to agree with you on this, Slow. I'd be more than glad to check any moisture meters anyone wants to send me. I have a lot of wood that is in the range of reading for most inexpensive meters (6-30% MC). If folks are interested, they should send them all at the same time and I'll run a small batch of the tested pieces through the MW and report the results here. If the things work, I might as well get one for myself. Keep in mind, though, these cheaper units are likely to vary somewhat between them compared to a pro unit like a Delmhorst.

Bear in mind, I did not have checking the burnability of individual firewood chunks in mind when I developed this test. It's purpose was to find an quick and easy method to determined the MC in wet wood so folks could keep track of the drying rates of their firewood during seasoning. The idea is to randomly pull and test a couple pieces from the stacks at regular intervals to see under what conditions and when in the year firewood dries the fastest. A moisture meter is useless for this purpose since they only read up to 30% MC, and virtually every wood in existence has a higher moisture content than that when green.
 
My $12.99 Harbor Freight model specifies a measurement range of 6%-42% for wood/paper/cardboard and 0.2%-2.0% for mortar/concrete/plaster. You select which mode you need to use. Whether or not it meets these specs, I don't know. Accuracy for wood below 30% moisture is stated as +/- 2% and above 30% as +/- 4%.
 
DanCorcoran said:
My $12.99 Harbor Freight model specifies a measurement range of 6%-42% for wood/paper/cardboard and 0.2%-2.0% for mortar/concrete/plaster. You select which mode you need to use. Whether or not it meets these specs, I don't know. Accuracy for wood below 30% moisture is stated as +/- 2% and above 30% as +/- 4%.

Wow! You'd have to spend $300 for a J-2000 from Delmhorst to get near that same range (6-40%). I wonder if there are any other differences between the two units? :roll: ;-)
 
You could purchase 10 from Harbor Freight, average the readings, and still save $170 (if you were interested in greater accuracy).
 
Dan, I think you're on to something there. And I could use the extra $170 to buy a new microwave for Lady BK. The old one smells like burning oak for some reason.
 
Carbon_Liberator said:
90% of the trees cut for firewood around here are dead standing. ..... many of the trees are dry enough to burn immediately, although not all of them. .... not all the standing dead trees out here are below 20% MC, so this is where a moisture meter can come in handy if you want to be real sure there is no chance of sticking a split in your stove that is over that 20% mark.

This is somewhat similar to my situation. When I bought my place in Oct '08 I began cutting dead standing and laying trees and some live trees that were in my way, mostly for firepit wood. There was oak, elm, black cherry, box elder, cottonwood, and maybe a few other species. I was cutting them about 16" and trying to keep them stacked according to species and approx. moisture content knowing I may get a wood stove someday. Well I'm at that day thanks to the available tax credit. So I see the benefit of having a moisture meter to help me sort through my existing 3 cords and any other mix of wood piles I'll generate going forward. I'll obviously still use the various other techniques to know what's dry and what's not, but pairing it with a moisture meter on occasion seems like it might be a good idea.

With that said - for those of you who believe in moisture meters and/or have one - any recommendations on a decent meter less than 100 bucks? Less than $50 would be even better. Thanks!
 
MinnesotaGuy said:
Carbon_Liberator said:
90% of the trees cut for firewood around here are dead standing. ..... many of the trees are dry enough to burn immediately, although not all of them. .... not all the standing dead trees out here are below 20% MC, so this is where a moisture meter can come in handy if you want to be real sure there is no chance of sticking a split in your stove that is over that 20% mark.

This is somewhat similar to my situation. When I bought my place in Oct '08 I began cutting dead standing and laying trees and some live trees that were in my way, mostly for firepit wood. There was oak, elm, black cherry, box elder, cottonwood, and maybe a few other species. I was cutting them about 16" and trying to keep them stacked according to species and approx. moisture content knowing I may get a wood stove someday. Well I'm at that day thanks to the available tax credit. So I see the benefit of having a moisture meter to help me sort through my existing 3 cords and any other mix of wood piles I'll generate going forward. I'll obviously still use the various other techniques to know what's dry and what's not, but pairing it with a moisture meter on occasion seems like it might be a good idea.

With that said - for those of you who believe in moisture meters and/or have one - any recommendations on a decent meter less than 100 bucks? Less than $50 would be even better. Thanks!
As stated before and in other posts I think the Harbor Freight cheapie is more than good enough for us wood burners, unless you break it as on person did (prong broke) it will do the job, no need for super accurate readings as this is not rocket science. The readings I get from mine are in line with the wood I have cut this spring, last fall, last spring, two years ago plus taking in account the different types of wood (ash, mulberry, oak, locust, silver maple) so save your self some money and but the cheapie.
 
What Oldspark said.

You can also pick them up quite cheaply (20 bucks or so?) on eBay. I got mine from there and it arrived within just a couple of days despite the fact that it came from Hong Kong!

One word of warning, though, about those prongs Oldspark mentions. You want to get them as deep into the wood as you can, but the cheap meters aren't strongly built enough to do that easily without risking breaking off the prongs. I push mine into the wood far enough to make a couple small marks, then use an awl or similar to make the holes deeper, then put the meter prongs back in to take the reading. (And don't forget you need to split whatever piece you're gonig to test first so you're getting a reading from the interior, not the much drier exterior.)

I don't know that you're really going to need one much, though. If you started in '08, you'll have plenty of dry stuff to play with and you'll quickly be able to tell the difference between dry and unseasoned, or semi-seasoned, wood just by the heft of it.
 
Sorry, I didn't see the Harbor Freight meter posted. I just bought one for $19.80 shipped.

I know I don't really need one, but I want one. Most of my wood was cut in '09 and '10. Thanks for the awl suggestion, I'll try doing it that way.
 
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