Dry wood vs Wet wood

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sweedish

Burning Hunk
Feb 6, 2019
226
Michigan
I had a oak quartersawn into boards, and took them to get then milled into floors, but first off to a kiln. The Miller said that the lowest Mc air dried boards he sees are only 14%.
 

McKraut

Feeling the Heat
Sep 1, 2011
291
South Central PA
Not a bad idea! Should also be mandatory for anyone buying a new stove or boiler.
 
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McKraut

Feeling the Heat
Sep 1, 2011
291
South Central PA
Sorry, I was trying to quote EJL923 "new members should be forced to watch that video before activating their account. "
 
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RockyMtnGriz

Burning Hunk
Apr 19, 2019
122
SW Montana
I got a MM with my furnace. The main problem I have with using it is the standard that the wood should be at 70 degrees. If I had stuff at 70 degrees regularly, I'd have so much less use for wood!

Seriously - does anybody have any real info on how temperature affects the readings? Being able to convert to 50 or 20 would make the thing usable.

Not that it's hard to tell with softwood if it's dry or not, but it would be a fun toy to have to compare to the moisture levels so many people post about.
 

kennyp2339

Minister of Fire
Feb 16, 2014
5,937
07462
I got a MM with my furnace. The main problem I have with using it is the standard that the wood should be at 70 degrees. If I had stuff at 70 degrees regularly, I'd have so much less use for wood!

Seriously - does anybody have any real info on how temperature affects the readings? Being able to convert to 50 or 20 would make the thing usable.

Not that it's hard to tell with softwood if it's dry or not, but it would be a fun toy to have to compare to the moisture levels so many people post about.
Your not testing every piece of every batch, you testing the pile, so bring a couple random splits inside, let them warm up, re-split and test, if its in the ball park and batch was cut and split at the same time and kept in a place were the batch is kept together, 3 or 4 random pieces will tell you whether the whole pile is good or not.
 
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Reactions: Bad LP
Aug 12, 2020
86
Parkers Lake, KY
As far as drying wood, I figure that it takes over 12 months for almost anything to cure properly. If my supposition is true, you can test almost any part of your stacks in mid summer when everything is at 70° and have a real good idea what will be ready when fall comes around and everybody lights their fires for the heating season.

I've been using a sharpie marker to write the date stacked on the ends of a few pieces in each stack. So far, I can read the date for months but I don't have anything that is a year old yet so my "dating method" hasn't really been tested long enough but I believe that it'll prove out. Once the stack exceeds 12 months of curing time, I'll be interested in testing moisture content; until each stack passes 12 months, it's a moot point.

So, if I CSS any wood like the hickory I finished yesterday, I figure it won't be ready to test for 12 months, like the hickory will be tested next spring and I won't need to burn it until next fall which would put it cycle for use after almost 18 months of curing time. Should be good by then but like I say, I'm new at this and this is only my theory that I haven't proven out yet.

I figure if you're trying to burn anything before it's cured 12 months, you're wasting energy in BTUs lost and frustrating yourself trying to keep a fire going using wet wood. Just my $.02 worth and not worth the paper it's written on...
 

NickW

Minister of Fire
Oct 16, 2019
520
SE WI
There are "general rules" for drying times of different species. Obviously will depend on climate and how it is stored. I found a BTU chart that includes them. Most pines are 6 mo, other softwoods (silver & red maple, box elder, Aspen, etc.) generally 1 yr, ash 1 year, elm 18 mo, birch-maple-locust-hickory 2 years, oaks 3 years...

Some claim to get oak ready in 1 year in a tight shed elevated off the ground, others won't use it in under 4 years.

I seperate by species now when stacking after last year having to sort through my stacks and pull out the ash for burning and leaving the maple to season longer. It was my first year with an EPA stove.
 

weatherguy

Minister of Fire
Feb 20, 2009
5,805
Central Mass
If you cant get oak ready in two years you need to find a new place to stack where its exposed to sun and wind. I know not everyone has that option but two years where I stack and it's down to 20%.
 
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begreen

Mooderator
Staff member
Nov 18, 2005
89,580
South Puget Sound, WA
If you cant get oak ready in two years you need to find a new place to stack where its exposed to sun and wind. I know not everyone has that option but two years where I stack and it's down to 20%.
Drying time also depends on the split thickness. Locally a friend is testing this with 3" thick oak splits that was stacked last summer. We'll be checking it around August to see how it's doing.
 

RockyMtnGriz

Burning Hunk
Apr 19, 2019
122
SW Montana
I had the opportunity to cut a little bit of wood over the weekend. Since the idea was for this wood to go straight from the forest to the furnace, I was close to the house with a warm furnace room, and able to do some moisture meter temperature correction experimenting. This is all lodgepole pine, standing dead for 5+ years, on a south facing slope in full sun. This is the driest time of the year here for standing dead here if it's on a south slope, except maybe during the peak week or few of fire season.

For what it's worth to you, here's what I found, by approximate temperature:

Tree top: 40 deg - 4%, 70 deg - 6%
Tree trunk: 40 deg - 8%, 70 deg - 11%

Different tree:
Base - 2nd round up: 45 deg -13%, 70 deg - 16%

I thought that was interesting! It's too small of a sample, but the difference sure was consistent! I wonder if the difference would hold in wetter wood, and I'm going to take a guess it probably wouldn't across species.