Soaked Uncovered Stack moisture content Readings.

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bigealta

Minister of Fire
May 22, 2010
1,839
Utah & NJ
Interesting Results here on Ash CSS 4/2023.
Tested at 38F so some adjustment in numbers is called for.
It's been rain and fog for many days in a row. Stopped raining yesterday.
Temps were mostly in the 40's F. for the rain / fog days.

This is the uncovered stack here in shade in NJ. The tested split was on the top row.

The 1st 3 readings are on the exterior 31, 11,16.
The rest are on the just split. Notice the last 16.3 right next to the soaked slightly punky layer.

3699CA16-8392-4C05-AD11-ECE113F087F8.jpeg CF760D66-C9A5-4526-B09D-D20603CF61A7.jpeg C21412D8-926D-4E62-A314-CBDBD920B2A9.jpeg EC63DFE0-7E49-452A-8AD0-8EE0DA339F43.jpeg E632E726-1739-4050-A2A9-B50D4CE06BB3.jpeg EACBF52F-481D-4D5E-A6CB-0E2AA7D53F4C.jpeg 9A294502-91BC-4F4D-98B2-461E31E1970A.jpeg D104B3BB-9838-4FA7-A649-4230164940E9.jpeg 200DB0B4-4404-4F64-B88A-70FD44BB5231.jpeg E568CA14-F627-4A64-907E-E64D916A3306.jpeg
 
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I've got the splits next to the stove now to dry the outside soft layer. Will report back how it burns when dried out. Tomorrow.
 
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Here is the same test with Oak.
CSS 1/2022
Again, the 1st 3 pics are Exterior readings.
Last 6 are on the fresh Split surface.

3E2CC92F-BEB2-4F62-92B9-428242F0B513.jpeg EE850079-9BFC-4E69-9612-7BF5C09C49F6.jpeg 61552239-4A88-4534-B9BA-77A7D70BBF2E.jpeg 7B68D157-D67A-4F40-B70B-71583F762E42.jpeg AC6C401E-844E-4BD0-BEE7-76ACF18A5FC3.jpeg 6AB8BEE8-DDC7-4167-A382-BD314F8DDD8A.jpeg 3DA308AC-565C-4CB4-9BF1-6B1F25B8B107.jpeg D1224444-4C88-463D-A0F2-F5ABF035275F.jpeg 76D47B5F-696D-41A1-9ADF-1E60EEADBE39.jpeg 062AAFA1-D848-4333-B1E9-DADA0D7D74F2.jpeg 53A7AA33-9F46-4D9C-8013-CA5443FE1344.jpeg 3BB2A4C5-448F-434E-A678-6369C11BF66D.jpeg
 
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Your pins are barely in imo. They need to be fully in for an appropriate reading. This was about the ash. I get the pins in completely and it makes a big difference for me. (In oak it's hard to get more than 2/3 of the pins in).
And the 16.7 reading crosses growth rings.
 
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Yes you are correct. Here is the ash pushed in about as far as can go without breaking pins.

63023DD2-D7E2-4397-BFD2-5F2AB233C05C.jpeg 3583CC4A-0B7D-4E0D-BEE5-0B582A1FF4DE.jpeg
 
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I had a large wet piece of oak that was on the end of a top covered stack. Brought it in and let it dry for two days. Resplit it and it was 19.2 so back in the stack it went until next year. I really want my oak in the 12-16% range. I recently had a large split that was 21%. Both of these splits were IMO too large to begin with.
 
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I have three 40 lbs 8"+ square maple pieces in my shed. I'm 4 years I'll weigh the again and hopefully burn them...
 
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Oak is the destroyer of moisture meter pins, it's impossible to get them all the way in. Over the years I've stopped trying. I've used so much oak and maple I just know what dry feels/sounds like. Its just obvious once you pick one up or bang them together and the stove will provides instant feedback on reloads to confirm.

Once in a while I'll take out the meter to test how a stack is doing and share the results here but that's more for fun than anything else.
 
Yeah i posted this thread to show what results can be with uncovered stacks. Just adding info to help make stacking type decisions.
 
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Oak is the destroyer of moisture meter pins, it's impossible to get them all the way in. Over the years I've stopped trying. I've used so much oak and maple I just know what dry feels/sounds like. Its just obvious once you pick one up or bang them together and the stove will provides instant feedback on reloads to confirm.

Once in a while I'll take out the meter to test how a stack is doing and share the results here but that's more for fun than anything else.
Yup nothing like the hollow ring tone on the driveway from seasoned oak.

I do feel the moisture meter works well on a fresh spilt and pins do not have to be very deep. Moisture from a fresh split in the center will be present for the meter to read. I take my reading immediately. Anything 19% or over will get another year in the stacks.
 
Yup nothing like the hollow ring tone on the driveway from seasoned oak.

I do feel the moisture meter works well on a fresh spilt and pins do not have to be very deep. Moisture from a fresh split in the center will be present for the meter to read. I take my reading immediately. Anything 19% or over will get another year in the stacks.
I've often wondered why people recommend driving the pins in as far as possible on the face of a fresh split. That's why you test on a fresh split, right?
 
I did see the readings change by 1 to 2% on those reading from "pushed in just snug" to pushed in
"as hard as possible" without breaking pins.

So the above readings of 17.2% and 17.9% were actually 19.2% when pushed in hard.

The take away for me is most readings are probably a couple % below what the actual moisture content is, as most people including me are not jamming their meters in to the breaking point with every read.
 
I've often wondered why people recommend driving the pins in as far as possible on the face of a fresh split. That's why you test on a fresh split, right?
Agree you are testing the pins in the center already. Sometimes I think we over think things. I do feel you should test the split right away.
 
I did see the readings change by 1 to 2% on those reading from "pushed in just snug" to pushed in
"as hard as possible" without breaking pins.

So the above readings of 17.2% and 17.9% were actually 19.2% when pushed in hard.

The take away for me is most readings are probably a couple % below what the actual moisture content is, as most people including me are not jamming their meters in to the breaking point with every read.
my splits are in the house for two days before testing and I take the reading immediately. My pins are in but I don’t jam them in. No need to.
 
Agree you are testing the pins in the center already. Sometimes I think we over think things. I do feel you should test the split right away

my splits are in the house for two days before testing and I take the reading immediately. My pins are in but I don’t jam them in. No need to.
In the ash it made a difference. I took readings immediately after split. I saw the readings change with my own eyes. Ok i'll do a video.
 
Don’t need a video since your variables might be different than mine. I know what works for me. Again I think we are overthinking this. I want my wood 18% and under which leaves a margin of error or 2%.

Also Ash drys much quicker than oak.
 
Yeah I'm not saying jam them in full all the time. A fresh split face is just that, the surface is an appropriate place to measure.

I just think in general as you get more experienced burning you don't need the meter anymore. It just becomes obvious to you. It's a nice tool to confirm your knowledge though and for when you really want #s for sake of discussion or an experiment like a new stacking method etc.
 
Yeah most of us here know dry wood by feel and how it burns. But there are a bunch of new guys that don't have this experience yet. And even us old guys can dial in our game or just confirm or reconsider our long held beliefs.
 
Yeah I'm not saying jam them in full all the time. A fresh split face is just that, the surface is an appropriate place to measure.

I just think in general as you get more experienced burning you don't need the meter anymore. It just becomes obvious to you. It's a nice tool to confirm your knowledge though and for when you really want #s for sake of discussion or an experiment like a new stacking method etc.
100% agree with you.
 
Yeah most of us here know dry wood by feel and how it burns. But there are a bunch of new guys that don't have this experience yet. And even us old guys can dial in our game or just confirm or reconsider our long held beliefs.
I'm never wrong. Just ask my wife...😂
 
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I agree with not needing the MM much; the wood was under a roof for three + years. If the roof is good, the wood is good.

The reason for the pins needing to be in (for a more accurate measurement) is two factors.
1. Contact resistance. A two-point measurement is susceptible to the influence of the resistance between metal and wood. (A four probe measurement would not be.)
This resistance is in series with the resistance of the wood. I.e. it adds.
The smaller the contact area is (shallower pins), the higher the contact resistance. The higher the resistance of the circuit the lower the moisture content read out. So shallow pins give an artificially low incorrect moisture content.
2. Spreading resistance. The more the measurement is two-dimensional, the higher the spreading resistance in the wood. The more 3D the measurement is, the lower. This has to do with the electric field distribution in the wood.
The deeper the pins are, the more 3D the measurement is, and the less the spreading resistance adds to the measured value.

Bottom line, the deeper the pins the better the measurements (less systematic error that suggests drier wood than it is).

After all the pins are there for a reason. Otherwise they would have made a surface contact probe without pins to push into the wood.

Regardless, it's not going to add 10 pct to your moisture. A few percent yes.(and then a few percent if you measured at 32 F rather than 70 F as per the calibration).
 
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I agree with not needing the MM much; the wood was under a roof for three + years. If the roof is good, the wood is good.

The reason for the pins needing to be in (for a more accurate measurement) is two factors.
1. Contact resistance. A two-point measurement is susceptible to the influence of the resistance between metal and wood. (A four probe measurement would not be.)
This resistance is in series with the resistance of the wood. I.e. it adds.
The smaller the contact area is (shallower pins), the higher the contact resistance. The higher the resistance of the circuit the lower the moisture content read out. So shallow pins give an artificially low incorrect moisture content.
2. Spreading resistance. The more the measurement is two-dimensional, the higher the spreading resistance in the wood. The more 3D the measurement is, the lower. This has to do with the electric field distribution in the wood.
The deeper the pins are, the more 3D the measurement is, and the less the spreading resistance adds to the measured value.

Bottom line, the deeper the pins the better the measurements (less systematic error that suggests drier wood than it is).

After all the pins are there for a reason. Otherwise they would have made a surface contact probe without pins to push into the wood.

Regardless, it's not going to add 10 pct to your moisture. A few percent yes.(and then a few percent if you measured at 32 F rather than 70 F as per the calibration).
1000001354.gif


😉. It's out of love. Good explanation!
 
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Now here is the proof for Stoveliker's explanation.

 
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And a follow up on the soaked ash after 1 day by the woodstove. Fresh resplit results.

Ext. went from 30.6 to 5.5, but this is soft wood so the 5.5 seems questionable. It's dry though no doubt.

Interior readings 19 and 20.7. Greater than yesterday but probably because i could sink the meter deeper on this split.

So my take away is i'll stay with my uncovered single row stacks.

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I suspect the outside is just a bit rotten and throwing the meter off. You can't get 5.5% wood outside naturally unless you're in a legit desert. The ambient humidity is just too high here. I think 12-16% is perfection in the northeast.
 
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