Can I trust these moisture reading levels?

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max384

max384

Member
Nov 28, 2015
97
Eagle Rock, PA
I just bought a General MMD4E moisture meter. I'm hoping these readings are accurate, but I'm concerned they may not be.

I just tested some wood and here is what I got:

Newly split white oak, from a log I got from a dump pile, still has bark on: 18-20%
Newly split red oak, from a log I also got from a dump pile, with bark still on: 16-18%
Newly split white oak (I think) from a log from the dump pile, older, with bark missing: 8%
Old seasoned wood (mixed species), split and stacked four years ago: 5-7%, and some pieces would not even register readings
Newly split mixed species that are obviously very dry from feel/sound: 6-10%
I sunk the prongs into a live white oak in my back yard: 41%

The reason I am concerned that these numbers may not be accurate is because of how long it is recommended to let oak season, particularly white oak, after splitting to be properly seasoned. Virtually everything I tested was at or below 20% moisture. I know that lower is better, but I was expecting higher numbers. To be fair, I don't know when any of these trees were cut down, since I scavenged the downed logs from a shrub/branch/root/log dump. However, most of the oak trees' bark looked to be very fresh. The one thing that gave me encouragement was that the live tree read over 40%, however, I'm not sure what a normal reading on a live tree is.

What do you guys think? Does it sound accurate? Did I just luck out with scrounging wood that is already partially seasoned before splitting? Or is my moisture meter faulty?
 
What does the palm of your hand read? Should be around 33%. Dimensional lumber in your house used for framing should be less than 10.
 
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gzecc said:
What does the palm of your hand read? Should be around 33%. Dimensional lumber in your house used for framing should be less than 10.
Click to expand...

+1 on this info. I have returned a mm when I got similar readings.
 
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These moisture meters are cheap enough to try another. I just don't see getting cord wood under 10% MC without kiln drying it. Maybe I'm wrong, but something seems off.
 
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claydogg84 said:
These moisture meters are cheap enough to try another. I just don't see getting cord wood under 10% MC without kiln drying it. Maybe I'm wrong, but something seems off.
Click to expand...

I agree I have never seen cord wood below 10%.
 
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I kind of feel like 0 = 5% on mine but your 2x4 seems about right.
 
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Is there any way you can borrow one to check against yours? Or find some splits that have a known MC from someone?

An absolutely green split should be around 40, so the live oak would be fine if you got under the bark. Your palm reading is about right. The old 2x4 is about right (I just measured one here)

The only questionable readings are on the dump pile which you don't know the history of. Yes, the <10 readings are weird, but could be explained perhaps. All the other readings you have seem quite normal. The palm thing works pretty consistently (mine is 35), but could vary of course.

My guess is that you're okay, but you do need to verify on some known samples or another meter. You certainly want to be comfortable with your meter. The model is a well respected one.

Last resort, exchange it and try again... You should be able to find the same model locally from HD or Lowes maybe.
 
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Are you reading the ends or the sides? Your palm and kiln dried numbers are correct.

Are these other numbers the numbers you see when you split open a split, set the pins in parallel to the grain lines and then take a reading?

I could see not spliting splits open you might see numbers like this at the surface even if there is a bunch of water still in the middle of the split. Also, if you are poking your pins into the end of a splitm, that parts is going to dry faster than the middle too.

Anyway, your palm and KD numbers are believable, the meter is probably working OK.
 
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I'm wondering if this was user error...

I tested the sides of the split, not the ends, but I don't know if I set the pins parallel to the grain or not. I never paid any attention.

I did not re-split any of the splits. Most of what I tested was split within the last week. Should I still re-split wood so freshly split? The four year seasoned wood was not re-split.

I work until after dark today, so I'll recheck tomorrow to ensure that these results aren't the result of user error.
 
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max384 said:
I'm wondering if this was user error...

I tested the sides of the split, not the ends, but I don't know if I set the pins parallel to the grain or not. I never paid any attention.

I did not re-split any of the splits. Most of what I tested was split within the last week. Should I still re-split wood so freshly split? The four year seasoned wood was not re-split.

I work until after dark today, so I'll recheck tomorrow to ensure that these results aren't the result of user error.
Click to expand...

Yes, you need to split, and then test.
 
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claydogg84 said:
Yes, you need to split, and then test.
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+1. What you are interested in is the center of the piece. Think of the drying process being from the outside in. Any exposed surface can start to dry pretty quick, so you need to get to the inside. You need to sink the pins in a ways too, but not enough to stress the meter. The harder the wood, the less they will sink in.

So far, It sounds like the meter is fine.
 
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Sounds like the meter is fine and the user has not correctly made the measurements.

I always split the wood at the time I am going to take any measurements.
 
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Mag Craft said:
I always split the wood at the time I am going to take any measurements.
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Yeah, you just have to. This stuff can be very confusing at first. It was for me with no fore-knowledge, but after a little time with the wood and good advice like from this forum, it becomes much more clear.

The OP Max394, (the apparent crotchrocket lol) is ahead of most by being aware of the issues and getting the meter to help. I still use mine, but less frequently than I did the first few years, depending on the nature of the freebies I find....Plus I'm three years ahead now.
 
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Sprinter said:
Yeah, you just have to. This stuff can be very confusing at first. It was for me with no fore-knowledge, but after a little time with the wood and good advice like from this forum, it becomes much more clear.

The OP Max394, (the apparent crotchrocket lol) is ahead of most by being aware of the issues and getting the meter to help. I still use mine, but less frequently than I did the first few years, depending on the nature of the freebies I find....Plus I'm three years ahead now.
Click to expand...

I hear ya. I am a good three years ahead also but I still like to take a reading once in awhile I guess from curiosity and peace of mind.
 
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Sprinter said:
Yeah, you just have to. This stuff can be very confusing at first. It was for me with no fore-knowledge, but after a little time with the wood and good advice like from this forum, it becomes much more clear.

The OP Max394, (the apparent crotchrocket lol) is ahead of most by being aware of the issues and getting the meter to help. I still use mine, but less frequently than I did the first few years, depending on the nature of the freebies I find....Plus I'm three years ahead now.
Click to expand...

It's not exactly a crotch rocket. It's a Suzuki SV650 that I've turned into a touring bike. Custom seat, lowered pegs, larger bars, full luggage, automatic oiler, etc. Eventually I want to upgrade to a beemer... But in the meantime, this bike has gotten me all around the continent. I've dipped its tires into three oceans, It's gone coast to coast, and it's taken me on a lot of great trips.

I'm heading home soon, and I'll test out some more of the wood and see where we're at.

Thanks for all the help everyone!
 
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Just a theory but the wood could have been standing dead before being cut down and paced in dump. That would explain the mid teens readings. If so that would be ready to go next season. +1 on double checking tho. Once you get 4 years ahead, meaning u have 3 years to season everything, u really do not need the meter. Just for curiosity.
 
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max384 said:
It's not exactly a crotch rocket. It's a Suzuki SV650 that I've turned into a touring bike. Custom seat, lowered pegs, larger bars, full luggage, automatic oiler, etc. Eventually I want to upgrade to a beemer... But in the meantime, this bike has gotten me all around the continent. I've dipped its tires into three oceans, It's gone coast to coast, and it's taken me on a lot of great trips.

I'm heading home soon, and I'll test out some more of the wood and see where we're at.

Thanks for all the help everyone!
Click to expand...
Sounds like a terrific touring bike. Love the bike story, as I always do. My customized Sportster has only seen the Pacific waters. I envy you your trips. You can't go wrong with nearly any Beemer when the time comes. You may never go back to anything else.

Shiny side up.;)
 
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My wife had a honey do list for me, but I managed a couple readings.

White oak, not re-split before reading: 18%
After re-splitting: 26%
For year seasoned wood, not re-split: 6%
After re-splitting: 14%

It looks like not re-splitting is what Gabe me the erroneous numbers...

Thanks everyone.
 
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max384 said:
My wife had a honey do list for me, but I managed a couple readings.

White oak, not re-split before reading: 18%
After re-splitting: 26%
For year seasoned wood, not re-split: 6%
After re-splitting: 14%

It looks like not re-splitting is what Gabe me the erroneous numbers...

Thanks everyone.
Click to expand...
Looks good to me. Happy burning! And good going on being diligent about moisture content. It is important.
 
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Sprinter said:
Sounds like a terrific touring bike. Love the bike story, as I always do. My customized Sportster has only seen the Pacific waters. I envy you your trips. You can't go wrong with nearly any Beemer when the time comes. You may never go back to anything else.

Shiny side up.;)
Click to expand...

I envy my trips too. I'm married and work too much now. I'm going to do another trip within the next decade though...

Got any pics of your Sportster?
 
max384 said:
I envy my trips too. I'm married and work too much now. I'm going to do another trip within the next decade though...

Got any pics of your Sportster?
Click to expand...
I'm retired now and understand. Take advantage of your youth. I'll look for a pic.

BTW, Our motto here on this site is : "Pics or it didn't happen"... I guess it' my turn....
 
max384 said:
My wife had a honey do list for me, but I managed a couple readings.

White oak, not re-split before reading: 18%
After re-splitting: 26%
For year seasoned wood, not re-split: 6%
After re-splitting: 14%

It looks like not re-splitting is what Gabe me the erroneous numbers...

Thanks everyone.
Click to expand...

Its not that your moisture meter gave you erroneous numbers, it that it can only measure the moisture content between its tines. It is a spot measurement tool only. The readings that you got were probably all quite accurate. You are using a moisture meter to determine if the inside has dried out. You are not getting the actual content of the piece of wood as a whole.
 
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