Shopsmith Forums

After many years of toying with the idea of purchasing a moisture meter, and being turned off because of the high price for a Wagner (Approx. $300) meter, I am reconsidering for a few reasons.
Up until now, I normally purchase lumber, and allow it to adjust to the temperatures in my garage for 2 to 3 weeks, if not sometimes longer before I start working on a project.
With the great information concerning moisture content, etc. that I received from Chuck, I started looking for a moisture meter that was more in my price range.
I came across one that is currently on sale for $29.95 until 09-02-08, normally $40.00, from Pennstate. http://www.pennstateind.com/store/mmeter.html
My question is has anyone purchased this particular meter, and how effective is it?
Any and all information would be appreciated!

John:D

John,

I bought this one from Woodcaft and like it very much http://www.woodcraft.com/family.aspx?familyid=20266

Jim

The MD-2G and -4G moisture meters are made in China for Handsun Enterprises, if that's relevant. The Sonin 4-in-1 Multifunction Detector from Woodcraft is also made in China by Optics Planet.

With all good wishes,

"...I normally purchase lumber, and allow it to adjust to the temperatures in my garage for 2 to 3 weeks, if not sometimes longer before I start working on a project."

Just so you know, a moisture meter won't allow you to use the wood any sooner, nor will it tell you when the wood is ready to use.

What you are doing is call "shop drying," -- a smart practice no matter what kind of meters you own. Most commercial furniture-grade lumber is kiln-dried to between 8% and 10% moisture content. This immediately begins to change from the moment the lumber is taken out of the kiln. Wood is hygroscopic -- it absorbs and releases moisture from the atmosphere depending on the relative humidity of its environment. When you bring it home from the lumberyard or into your shop from the barn, there is a difference in the relative humdity between locations. The wood will begin to absorb or release moisture and in doing so, will shrink or swell. You don't want to use that lumber until it has shop-dried, acheiving an equilibrium with the relative humidity in your shop and ceasing to move.

A moisture meter will not tell you when the wood is at equilibrium, particularly a cheap meter with an accuracy range of +/- 1%. If you had a better meter, you might be able to compare the moisture content of the newly-arrived lumber with boards that have been hanging out in you shop for a few months, but that's still not going to save you any time. You will have to keep on doing what you've been doing.

With all good wishes,

Nick is absolutely correct that a meter will not help your wood to reach equilibrium any faster than without one. However you would be able to tell the difference between just purchased wood and the stuff that's been in your shop for quite a while. For my recent project of end tables, I had to wait about 6 weeks to gain a measured EMC. The rule of thumb 3 weeks, just wouldn't have done it in this case. I had even partially sawed out some of the work pieces to make smaller pieces to lose moisture.

Exact moisture detection is a pretty nebulous thing, but a meter will tell you differences enough to avoid manufacturing mistakes. Whether pin-less or pinned, all meters have an inability to tell the difference between varying densities in a board. Also they all need to be calibrated or corrected for different species of wood.

Yes, I like the pin-less feature of the Wagner 209. No little holes to present issues. I'll have to admit mine cost about $100 less than today's price, but I found one at Rockler for $239.99.

FYI thought I'd throw in a page of FAQs re: the Wagner

http://www.wwwagner.com/faqs.php?langua ... geid=29#17

As always, I can count on receiving some great information from this forum, and sometimes more important, additional thoughts or viewpoints.
My practice of allowing purchased wood to "condition itself" is something that I learned a long time ago.
My interest in a moisture meter is for those opportunities that come by once in a while where one has the chance to pick up some free wood, such as wood rounds from tree cutting.
With purchased lumber, as stated by Nick, you are assured of a certain level of moisture. Wood taken from a recent tree cutting requires a drying process, and a means to check the moisture level.
Thanks again Nick! My search for a meter did not encompass place of orgin, and now I know.
And once again, Chuck, Thank You! I will now only consider "pointless" meters, and will consider your recommendations!

John

My problem is poor planning or bad estimation of needed supplies.
Often in my projects I figure out how much wood I need. I then go buy it and set it in my shop to acclimate. Then I begin building my project. Without fail I mess up a some wood, forgot to figure in something or otherwise end up short. I then jump in my car and run down to my lumber yard and buy an additional board or two. Now when I come home I know I should let it sit around and acclimate but I'm usually so anxious to get my project completed I just use it as I bought it.

Know what it usually works just fine and therefore I have to wonder at the everyone saying you got to let the wood acclimate.

To the best of my knowledge I have had only one failure in anything I built. I contributed it to glue starvation but everyone said I'm wrong. I know I had had to buy extra wood for that particular project so I do wonder if that was the wood or not. But even then only one failure in 20+ years of building furniture, remodels, and etc isn't all that bad of track record. I also know in almost every project I have had to buy extra wood which I used immediately in projects where I had aged my initial purchase of wood.
Ed

Guess I don't buy from the same place as Ed. I would say if the "buy and use it today" works for you - go ahead! It still is a lot safer to let newly purchased boards acclimate to your shop condition. Or compare the MC with the same species wood that's been in your shop for a while.

Most of my wood comes in an un-finished condition. Some, usually oak has been planed a little oversize on the two faces, but the edges are raw and not parallel. I swear, sometimes this stock has been air dried on the shores of the Pacific, and shipped on a rail car through the monsoons. My poplar is all 5/4 rough - moisture sometimes varies even in a single board. The good thing is - I don't have to pay the price of ripping and planing.

charlese wrote:Guess I don't buy from the same place as Ed. I would say if the "buy and use it today" works for you - go ahead! It still is a lot safer to let newly purchased boards acclimate to your shop condition. Or compare the MC with the same species wood that's been in your shop for a while.

Most of my wood comes in an un-finished condition. Some, usually oak has been planed a little oversize on the two faces, but the edges are raw and not parallel. I swear, sometimes this stock has been air dried on the shores of the Pacific, and shipped on a rail car through the monsoons. My poplar is all 5/4 rough - moisture sometimes varies even in a single board. The good thing is - I don't have to pay the price of ripping and planing.

Chuck
You made a point I didn't mention but usually when I buy a 'make up' piece of wood I buy dimensioned lumber stored under roof. I guess because of all the rain here in Florida most of the lumber yards keep their wood under cover and their dimensioned lumber neatly stacked, high and dry.

I tried to buy rough sawn wood but storage is a real problem. Either because of weather, bugs or space. First you don't want a pile of wood lying around if there is a hurricane. My friend watched 2000+ board feet of prime Cherry and Walnut float away, another watch a huge pile blow away. Second because the ground doesn't freeze bugs, especially termites love Florida so putting out a wood pile is like opening a termite ice cream store. Thirdly in Florida a basement would be an indoor swimming pools so there aren't any, therefore space is a premium. I only have storage for about 500+ board feet and it is usually such a mix I just do buy what I need for any project. Stand it on end in my garage/shop for a few weeks and begin to work it.

However even when I "stablize" my wood it is in my shop that does not have the air running all the time. So it sits in basically out door humidity and temperature until I'm in the shop with the air on and working the wood. At the end of the day I flip the air off and there it sits until the next day. Once finished it is usually moved into the house, where we use the Air conditioner almost non stop June through Sept then it gets flipped off until next June. We may turn the heat on a day or two through out Dec - Feb but usually it is off also.
I actually have more problem with wood movement from store bought furniture. Many times joints will open and I even had veneer failures.

Also here in Florida if I replace any wood on the outside of the house I usually now use either the new poly woods or cement board. I have had more door jams rot out. But the new PVC door jam and brick molding that is being sold last forever. Houses are mostly concrete block with southern yellow pine trusses and any inside stud walls use pressure treated sill plates and borax treated studs set on poured concrete floors. Some builder don't use the borax treated studs and that keeps the termite killers in business.

Wood here either inside or out is exposed to such wide swings in humidity I have got to beleive it would be impossible to get every piece of wood at the same water content at the same time.
Ed

Yeah! The unique conditions around Tampa are quite different from much of the rest of the Nation. That's for sure!

But here are some wild guesses bout your situation. Keeping in mind, I know nothing - just guessing:
I can understand why you see more problems with store bought furniture than home made. The store bought stuff was made in places where humidity is controlled to a lower degree than you have at home. I will take a wild guess that the wood inside your home has about 12% moisture content. It would vary a little according to the indoor humidity, but probably not more than a couple of percent. So you are sawing wood with a MC of around 12% to 13% and only changing that about 1 to 2% by bringing it int the house. Not the case with store bought stuff that was probably manufactured at around 8 to 9%. The adsorption would be greater than the desorption of your home made items.

Here are a couple of references if you have not seen them earlier. Both copied from the "Wood Handbook" from the U.S.D.A. , Madison, Wis.

Table 12–1. Equilibrium moisture content of wood, exposed to outdoor atmosphere, in several U.S. locations
in 1997
Equilibrium moisture content* (%)
State City Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.
AK Juneau 16.5 16.0 15.1 13.9 13.6 13.9 15.1 16.5 18.1 18.0 17.7 18.1
AL Mobile 13.8 13.1 13.3 13.3 13.4 13.3 14.2 14.4 13.9 13.0 13.7 14.0
AZ Flagstaff 11.8 11.4 10.8 9.3 8.8 7.5 9.7 11.1 10.3 10.1 10.8 11.8
AZ Phoenix 9.4 8.4 7.9 6.1 5.1 4.6 6.2 6.9 6.9 7.0 8.2 9.5
AR Little Rock 13.8 13.2 12.8 13.1 13.7 13.1 13.3 13.5 13.9 13.1 13.5 13.9
CA Fresno 16.4 14.1 12.6 10.6 9.1 8.2 7.8 8.4 9.2 10.3 13.4 16.6
CA Los Angeles 12.2 13.0 13.8 13.8 14.4 14.8 15.0 15.1 14.5 13.8 12.4 12.1
CO Denver 10.7 10.5 10.2 9.6 10.2 9.6 9.4 9.6 9.5 9.5 11.0 11.0
DC Washington 11.8 11.5 11.3 11.1 11.6 11.7 11.7 12.3 12.6 12.5 12.2 12.2
FL Miami 13.5 13.1 12.8 12.3 12.7 14.0 13.7 14.1 14.5 13.5 13.9 13.4
GA Atlanta 13.3 12.3 12.0 11.8 12.5 13.0 13.8 14.2 13.9 13.0 12.9 13.2
*EMC values were determined from the average of 30 or more years of relative humidity and temperature data
available from the National Climatic Data Center of the National Oceanic and Atmospheric Administration

And there is another "rule of thumb" table in Chapter 3 - table 3-4
http://www.fpl.fs.fed.us/documnts/fplgt ... 3/ch03.pdf

If you are so inclined, you can use the simple formula on page 3-8 (they named the formula (3-4) in the right hand column of that page) and substitute another (guessed at or measured) moisture content for the figure 30 in the numerator. It is kind of fun for weirdos like me.

Like they say - it is impossible to predict the actual shrinkage or swelling of an individual board, but you can predict averages.