# Moisture Meters



## kmwhalley (Dec 22, 2011)

Good evening,

I am in the market for a quality Moisture content meter to help monitor drying of milled lumber. I don't want to break the piggy bank, nor do I want to ruin a bunch of lumber. Any insight to products and processes that you all have done in the past would be great.

Thanks


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## aardvark (Sep 29, 2011)

You can spend from $50-500.oo+ It all depends on what breaking the bank means.
It also depends on your use

I bought a "General" brand at Lowes for $49.oo, and for what I'm doing it is adequate. I'm drying log burls and cuts for rustic furniture. My goal is a moisture of 8 to 10%, and if possible I try and get a fresh cut measurement on pieces when I cut and work them It's a 2 pin unit that is good enough to push in a solid 1/4" plus and get a good reading. If I was drying down to 4% and for use as fine joinery furniture or cabinet work, I would say the accuracy might be a tad questionable.


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## wmodavis (Dec 26, 2010)

Lot of good info here. Hope it will help you decide.


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## Dominick (May 2, 2011)

aardvark said:


> You can spend from $50-500.oo+ It all depends on what breaking the bank means.
> It also depends on your use
> 
> I bought a "General" brand at Lowes for $49.oo, and for what I'm doing it is adequate. I'm drying log burls and cuts for rustic furniture. My goal is a moisture of 8 to 10%, and if possible I try and get a fresh cut measurement on pieces when I cut and work them It's a 2 pin unit that is good enough to push in a solid 1/4" plus and get a good reading. If I was drying down to 4% and for use as fine joinery furniture or cabinet work, I would say the accuracy might be a tad questionable.


That's the one I have and seems to work good for me. I got it as x-mas gift. Not really sure how accurate it is.


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## Jim Moe (Sep 18, 2011)

I have a Sonin which is in the $40 to $60 range and it works great. I carry a small brad nail with it and mark the end of the board with the meter prongs and then tap the nail in a 1/4' or so and put the meter in the holes.


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## aardvark (Sep 29, 2011)

Dom 
For what we do it's accurate enough.
I would step up to better if doing fine joinery but also use a 2nd for double check in that scenario.
2 readings is better confirmation.

But for what we do...adequate to good.

(cut that oak and mounted it today... what a back breaker.)


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## Dominick (May 2, 2011)

It works Pretty good. Everything is 0% lol
Can't wait to see.


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## aardvark (Sep 29, 2011)

Is dry ice 0%?
Or a dry martini (shaken not stirred)?

Ha!

(Dom...Photo's sent this morning. Today I work down the top. Interior moisture was ~22-26%..better than I had expected)


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## djg (Dec 24, 2009)

Do a search on "Moisture Meters" here and you'll find a lot of threads on the subject. What I gathered from everyone's advice when I was looking at buying one is this:

There are basically two schools of thought on meters.
Inexpensive <$30 from BORGs

Amazon.com: General Tools MMD4E Digital Moisture Meter: Home Improvement

A few people here have mixed reviews; some like it, some don't.

More expensive, but not too bad.

Amazon.com: Lignomat Moisture Meter Mini-Ligno E/D: Home Improvement

Supposedly more reliable/reproducable, but I'm not really sure.
That's just my general opinion after reading through them.

I went with the Lignomat because I didn't want to chance having to buy a second one a year or two later.


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## ETWW (Mar 27, 2011)

The benefit of a moisture meter depends on it's use. If you are air-drying lumber, it will let you know when the lumber reaches EMC. 

For storing lumber, a hygrometer is a better investment than a moisture meter and lots cheaper, too. If you know the relative humidity, you can know the EMC of the lumber after it acclimates to it's environment.

Ideally, one has both and any serious woodworker does. 

I have both the Lignomat Mini-Ligno E/D ($100) and the General from Home Depot. ($30) For pin-type meters, they do a good job and read consistently within 1% of each other with the General giving the higher reading. The General was on sale a few months ago for $19...a very good deal, indeed.

If you want real accuracy, you have to step up to a pinless in the $200 plus range or, even better, use the oven-dry method.


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## woodnthings (Jan 24, 2009)

*I use this one*

I have had a lot of lumber milled off the property over the years and air dry it under cover. This meter reads 12 -14 % in wood that has been air dried here in Michigan. After 2 weeks inside it has acclimated to below 8% in the heated shop and I have used it with no shrinkage or checking. It was not that expensive and has multiple uses.
From www.ptreeUSA.com


*Multi Functional Moisture Meter*











The *Sonin Multi Functional 4-in-1 Stud, Moisture, Metal & Voltage Detector 50215* puts time, effort, and money saving professional quality







within the reach of homeowners, do-it-yourselfers and contractors at a value price. This *Multi Function Detector* detects Moisture percentages 8 - 22%, and helps find if potentially damaging excess moisture is present. Detect wood and metal studs, beams and joists behind walls up to 3/4 inch deep and non contact voltage detection helps you trace locate live AC wire behind walls or ceilings up to 2 inches deep. The *Sonin 4-in-1 Multi-Function Detector* is a microprocessor based instrument with automatic calibration to ensure accuracy. Locate hidden metal, steel, copper pipes, and frames(both ferrous & nonferrous) behind walls up to 2 inches deep easily with this *4-in-1 Detector*. 
*No.* *Description* *Price*​ *Quantity*​ *3451* 
*Multi Functional Moisture Meter*​ *$39.99* 
​


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## aardvark (Sep 29, 2011)

wood..

It's a bit limited in it's moisture reading range, but I assume accurate in that 8 to 22% range.
The "General" brand will read down to zilch and up to 50%. Cost is similar. I assume at the lower ranges it is less accurate, however.


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## Kevin07 (Feb 19, 2009)

dont mean to hijac this but, I was told by the man who milled some logs for me that my moisture meter is wrong. He said that even though it says 8% its not acurate. He said its probably more like 14% He says i need a meter where you type in the wood species? Aparently the diffrence in density has something to do with it idk im confused. He aslo told me that my dehumidifyer kiln would not get it down the furnature grade (6-8). I think hes wrong but i dont know much about this stuff. I have the general meter.


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## aardvark (Sep 29, 2011)

Moisture meters are like your bathroom scales measuring BMI. You have wet feet, the numbers can change.
It's not measuring wood density, it's measuring resistance or moisture.
Could density change things a tad? Ok, I'll bite on that, but the variance from 8% to 14% seems quite off. 2% off, I can buy, and meters are that much off. Especially the cheaper ones.


(so if I'm wrong, correct me)


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## Longknife (Oct 25, 2010)

Moisture meters are actually measuring the electrical resistance in the wood and that is a function of moisture and density, so density is a factor that should be considered. Matthias Wandel (Woodgears.ca) has written a couple of very interesting articles on the subject, here and here.


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## aardvark (Sep 29, 2011)

Thanks for the link.

The first article is nearly stating where I was going with my statement that I could see a few % in error, and that is expected in cheap equipment. 

When testing logs or rough cut wood, and only trying to verify % down to a ~10% or so level +or- 2ish %, I think the cheaper meters are sufficient.
If you are into fine woodworking and joinery, the need to be more accurate and into % ranges of 4-8% , good equipment gets critical. That is where better verification is needed.


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## ETWW (Mar 27, 2011)

Kevin07 said:


> dont mean to hijac this but, I was told by the man who milled some logs for me that my moisture meter is wrong. He said that even though it says 8% its not acurate. He said its probably more like 14% He says i need a meter where you type in the wood species? Aparently the diffrence in density has something to do with it idk im confused. He aslo told me that my dehumidifyer kiln would not get it down the furnature grade (6-8). I think hes wrong but i dont know much about this stuff. I have the general meter.


To get the average MC of lumber, you need to check it in several different areas. If using a pin-type meter, the outside lumber shell or case will often give a very low reading while the core is much higher because wood dries from the outside-in. If you cut a sample piece at least one foot from the end of a board and then rip that piece in two and check against the long grain, you will know the core MC.

Wood density does affect electrical resistance but not to the amount you noted (8% - 14%). A dehumidifier kiln WILL get lumber down to the 6% - 8% MC needed for furniture making. You were wrongly informed there.

Three things determine the rate of drying and how dry the lumber ultimately becomes...Heat, Relative Humidity and Air Flow. Of those three, RH is the most influential in determining the ultimate dryness of the lumber. Wood stored in an area of zero RH will eventually reach zero MC. That's known as oven-dry. Heating air lowers the RH and air flow facilitates evaporation of moisture from the wood surface.

Dehumidifying is also what a vacuum kiln does. If you remove all the air present (total vacuum) then the RH is zero.


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