Best moisture tester

[bruns333]

Do folks have a favorite moisture tester for a newbie. I have been reading many post and you all say the moisture content of my wood will make our first heating with a wood insert less troublesome.

Thanks for the info,
Matt

 

[Pagey]

For firewood, you can really get by with about any 2-pin meter. Some say that the 4 pin models are a little more difficult to use, as you need to achieve contact with 4 points on a not so smooth surface.

http://www.amazon.com/PSI-MMETER2-D...ref=sr_1_3?ie=UTF8&s=hi&qid=1251726341&sr=8-3

 

[mellow]

(broken link removed to http://cgi.ebay.com/Moisture-Meter-Wood-Woodworking-Timber-NEW-only-2-Pins_W0QQitemZ220472858737QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item335534d871&_trksid=p4634.c0.m14.l1262)

I just bought one of those last week and have been busy trying it out, works great so far and the guy ships them out quick.

 

[Wet1]

This is all you need...

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=67143

 

[thewoodlands]

My moisture meter just came in , HQRP MD-4G Wood / Firewood Moisture Meter. Will test some Beech,Maple and Cherry after work and post results.

Zap

 

[thewoodlands]

Here is the Moisture Meter that I purchased, it came in today.

Zap

 

[thewoodlands]

Here is another reading from some beech.

Zap

 

[North of 60]

Here is another reading from some beech.

Zap

Zap your gonna have to split that wood and check it from the middle to get any useful reading. Testing from the ends like that is not gonna tell ya much.

 

[maplewood]

Resplit any piece to measure the moitsture on the newly opened face. You'll be surprised that a previously split piece will read much lower than a round that is split for the first time.

 

[thewoodlands]

Will resplit some splits and take a reading tonight.


Zap

 

[wolfram]

Check out the following USFS article. You may already have a suitable "moisture meter" at the house.

(broken link removed)

With the table in the article, a common handheld voltmeter / ohmmeter will do the trick for most firewood applications. The article gives electrical resistance as a function of wood species and moisture content. Nice explanation of moisture measurements. Also addresses some questions regarding temperature dependence.

 

[Sleepy]

Check out the following USFS article. You may already have a suitable "moisture meter" at the house.

(broken link removed)

With the table in the article, a common handheld voltmeter / ohmmeter will do the trick for most firewood applications. The article gives electrical resistance as a function of wood species and moisture content. Nice explanation of moisture measurements. Also addresses some questions regarding temperature dependence.

Thanks for the great resource!

Ever compare readings from a moisture meter to an ohmmeter?

I was thinking about buying a moisture meter, but I already own a good ohmmeter.

 

[bruns333]

Thanks for all the great info. I just purchased a two pin model this morning from the ebay person.

Matt

 

[Hurricane]

I noticed in the article it says that you will get different readings if you stay with the grain or go across the grain. I tested this with my multimeter and it is true. How many people do it the same way all of the time and is it across or with the grain ? Against the grain I got a lower moisture reading.

I tested some pine that I split in Jan/Feb with moisture splashing out while splitting and it is now at 17% and also tested some oak I cut and split in Dec from a tree that was blown down for a few years and it is still at 27%. The tree was not sitting on the ground the root held it up off the ground. The other interesting thing in this article is the difference between different species of wood. Take black ash and red oak the same resistance reading of .6 M ohm's on ash is 20% moisture and on the oak it is 25% moisture.
How do the moisture meters compensate for this ?

 

[wolfram]

Hurricane, great comments and experiments. Most inexpensive "moisture meters" do not correct automatically for species. Some might come with a correction table, I think.

At the higher end, the Wagner MMC220, for example, includes a built-in lookup table for species and does the correction internally. But wow, is it expensive. I would rather buy a multimeter and use the Forest Service table. That way, I get a more accurate moisture tool that is also useful around the house and shop.

 

[Todd]

Still doesn't beat the bubble test. Take some liquid soap and smear it on one end of a split, turn it around and lock your lips on the other end and blow. If you start to see bubbles it's good to go. I'm not kidding! It works! Just don't let anyone see you doing this, it may be hard to explain.

 

[Hurricane]

Still doesn't beat the bubble test. Take some liquid soap and smear it on one end of a split, turn it around and lock your lips on the other end and blow. If you start to see bubbles it's good to go. I'm not kidding! It works! Just don't let anyone see you doing this, it may be hard to explain.

Can you post some pictures or maybe a video of the correct method of this test

 

[RustyShackleford]

Check out the following USFS article. You may already have a suitable "moisture meter" at the house.

(broken link removed)

With the table in the article, a common handheld voltmeter / ohmmeter will do the trick for most firewood applications. The article gives electrical resistance as a function of wood species and moisture content. Nice explanation of moisture measurements. Also addresses some questions regarding temperature dependence.

Wow, that's cool. More than you wanted to know ! I have a nice Fluke ohm-meter at home.
It would be nice if you could buy an electrode attachment for it, that gives the specified
penetrations of 5/16" spaced 1.25" apart; I guess you could make your own.

Also, remarkable how it varies by species - do the commercial moisture-meters have some
way of inputting what species it is that you're measuring ??

 

[wolfram]

Rusty, check out, for example, the spendy Wagner MMC220 (I think Amazon has them listed). You can input popular species.

Making your own fixture is the way to do. Two thru holes and two set screws will give proper spacing and depth.

 

[Nonprophet]

Check out the following USFS article. You may already have a suitable "moisture meter" at the house.

(broken link removed)

With the table in the article, a common handheld voltmeter / ohmmeter will do the trick for most firewood applications. The article gives electrical resistance as a function of wood species and moisture content. Nice explanation of moisture measurements. Also addresses some questions regarding temperature dependence.

Wow, that's cool. More than you wanted to know ! I have a nice Fluke ohm-meter at home.
It would be nice if you could buy an electrode attachment for it, that gives the specified
penetrations of 5/16" spaced 1.25" apart; I guess you could make your own.

Also, remarkable how it varies by species - do the commercial moisture-meters have some
way of inputting what species it is that you're measuring ??

If you read the text of the article it says that moisture content only varies 1-2% between the tree species found in the U.S. (in terms of calibrating the meter)--so to me 1-2% really doesn't seem worth worrying about......

I like the idea of using my voltmeter (I too have a nice Fluke) but the article also states that 5/16" penetration of the probe points into the wood is required to get accurate readings, and my existing prongs won't do that........Given that a decent digital moisture meter can be bought for $20-$30, that seems like the best bet to me.....

NP

 

[RustyShackleford]

Check out the following USFS article. You may already have a suitable "moisture meter" at the house.

(broken link removed)

With the table in the article, a common handheld voltmeter / ohmmeter will do the trick for most firewood applications. The article gives electrical resistance as a function of wood species and moisture content. Nice explanation of moisture measurements. Also addresses some questions regarding temperature dependence.

Wow, that's cool. More than you wanted to know ! I have a nice Fluke ohm-meter at home.
It would be nice if you could buy an electrode attachment for it, that gives the specified
penetrations of 5/16" spaced 1.25" apart; I guess you could make your own.

Also, remarkable how it varies by species - do the commercial moisture-meters have some
way of inputting what species it is that you're measuring ??

If you read the text of the article it says that moisture content only varies 1-2% between the tree species found in the U.S. (in terms of calibrating the meter)--so to me 1-2% really doesn't seem worth worrying about......
NP

Oh yes, I see. If you read down a given column, there seems to be huge variation among
species. But if you pick a certain resistance, say 20-megaohms, and see what moisture
level that corresponds to for the typical firewood species, it's NOT that big a variation:
it corresponds to 14 +/- 1 percent for hickory, oak, maple, ash.

Making your own fixture is the way to do. Two thru holes and two set screws will give proper spacing and depth.

You'd want something a lot sharper than any kind of screws, no ? Something very sharp yet durable.
And of course the fixture housing would have to be completely non-conducting.

 

[Sleepy]

I tried the ohms test on some wood I brought home Saturday. It was cut into 8' logs over a year ago and left on a pile on the ground. After cutting and splitting, I got out my good ohmmeter and the chart. Trouble was, the reading would not stay constant. The resistance reading slowly climbed and I really had no idea what I actually had.

So Sunday I ordered a moisture meter from Harbor Freight.

 

[Nonprophet]

I tried the ohms test on some wood I brought home Saturday. It was cut into 8' logs over a year ago and left on a pile on the ground. After cutting and splitting, I got out my good ohmmeter and the chart. Trouble was, the reading would not stay constant. The resistance reading slowly climbed and I really had no idea what I actually had.

So Sunday I ordered a moisture meter from Harbor Freight.

I would think that using an ohmmeter would be problematic because the ends of most probes are not sharp enough to fully penetrate the wood. I have a nice Fluke--I'll give it a try but I think my $30 feeBay moisture meter will do the job just fine!

 

[Sleepy]

I tried the ohms test on some wood I brought home Saturday. It was cut into 8' logs over a year ago and left on a pile on the ground. After cutting and splitting, I got out my good ohmmeter and the chart. Trouble was, the reading would not stay constant. The resistance reading slowly climbed and I really had no idea what I actually had.

So Sunday I ordered a moisture meter from Harbor Freight.

I would think that using an ohmmeter would be problematic because the ends of most probes are not sharp enough to fully penetrate the wood. I have a nice Fluke--I'll give it a try but I think my $30 feeBay moisture meter will do the job just fine!

I thought the same thing. No way can you push the probes in 5/16" as recommended. I ran two screws in 1-1/4" apart across the grain and had the same problem. The Harbor Freight meter was only $20 shipped. I hope it works.

 

[wolfram]

"You’d want something a lot sharper than any kind of screws, no ? Something very sharp yet durable.
And of course the fixture housing would have to be completely non-conducting."

Yes, sorry about that. I meant to imply that a suitable fixture could be designed & built to hold properly constructed sharp probes at the stated spacing. Set screws, among other methods, could be used to hold the sharp probes at the proper spacing and depth. Might even design the fixture to be tapped in with a mallet against a hard stop to ensure proper probe depth. Lots of things to try/play with.

Regarding buying a moisture meter, by all means. I just like to tinker and wanted to alert the group to the US Forest Service article. I believe that most store-bought moisture meters work on the same principle of measuring resistance and converting to a calibrated moisture percentage. The same issues remain in that the moisture meter probes need to be sharp/durable so as to be pressed to the proper depth to conform to the manufacturer's moisture calibration.

At the risk of sounding like a complete geek, it would be fun to run a controlled test of several lower-cost moisture meters to see where they stand. Maybe a project for a future winter!