Comparing moisture meters

An assessment of the performance of pin and pinless moisture meters made by major manufacturers. July 11, 2000

I need some help selecting a moisture meter. I just got a new bandmill and plan on milling a lot of lumber. I also plan on air-drying quite a bit of wood.

My main use of the meter will be in measuring rough lumber, but I am still concerned about the pinholes showing though, after planing the wood. I am debating between the Wagner L606 (pinless) and the Delmhorst J-2000 (pinned). They are the same price.

Are these good meters? Any others I should consider? Is there one that is both pinless and pinned?

Forum Responses
Electrophysics. They have a dual mode (pinned and pinless) meter for $330. Anyone have experience with it?

Do I understand that you will be using these meters on air-dried lumber? Why? What will you do with the info?

I think that you will have very expensive meters but the need for accurate data is limited. When you go into the kiln, you will have to cut normal moisture content (MC) sections. If you use a solar kiln, then the entering MC doesn't matter. In short, I do not think that you need a meter for air-dried lumber.
Gene Wengert, forum moderator

From the original questioner:
After the lumber is air-dryed, I want to bring it into the shop (which is the same temperature and humidity as the house) and let it finish drying.

I want to use the meter to see how far along in air drying it is, and then how dry it is once it has been in the shop for a while.

Gene's reply:
In that case, it seems that knowing the MC gradient would be especially critical for you, so the pin meter would be a good idea.

Actually, if you can afford both, you will find them both to be useful -- I like to suggest that about $200 is the minimum price to pay for a good meter. I also suggest that you get one that lots of other people use, to help in learning how to use it, special techniques, etc.

I have one of the Wagner pinless meters, and I'm using it to monitor MC in the yard, the solar kiln, the storage barn, and the furniture workshop. It's easy to use, has been accurate the few times I've had a way to check its calibration and the adjustment tables, and leaves me feeling confident in the MC of anything I'm about to use.

Regarding Electrophysics' moisture meter: I have both a pin and pinless. They are very reasonable in cost (under $200). My company also has two Delmhorst meters.

I have had very good results with the Electrophysics meters. They are fast, easy and reasonably accurate. In some cases, I have found them more accurate than the Delmhorst, when compared to oven samples.
I would be interested in hearing other comments. Currently, I only use the Electrophysics for quick checks, but would consider using them for more if they were industry accepted.

I did compare over 150 kiln-dry samples with the pin (Lignomat and Delmhorst) and the pinless (Wagner) meters. Although any one reading could be off, on the average all three meters were very close.

For example, the error was .5 percent, .7 percent, and -0.1 percent MC for the three meters on hard maple; .6, .5, and 1.2 on red oak; and .3, .9, and -0.1 on walnut.

See the Forest Products Journal Vol. 47, No. 6, pp. 60 - 62 for details. (These results are very good considering that the pin meter measures in a specific spot, the pinless in one half of the thickness, and the oven test in a large piece.)

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor J:
Many people seem to think that meters with pins are more accurate. They would be suprised to learn that pinless electromagnetic wave technology is more acurate and does not damage the wood. It is also easier to use in professional and private atmospheres.

Comment from contributor M:
The pinless or inductive moisture meters are more subject to interference (from things like metal) and are not reliable when used in any construction that involves nails, screws, pins, metal fasteners, etc. So, except for measuring moisture at the lumberyard, they are not a first choice. Also, I've seen widely divergent readings from inductive MM in the same location when taken one after the other. I'm not really a fan of Pinless either.