What moisture meter

What is best for testing moisture content of wood, a two pin or a four pin tester?

Andy.

Reply to
handy-andy
Loading thread data ...

"handy-andy"

How about no pins...

formatting link

Reply to
RzB

Good grief! That's $300 for a hobbyist grade moisture meter.

No wonder the Brits are so pale ... they're being bled to death!

Bill

-- Time you enjoy wasting, was not wasted. John Lennon

Reply to
Bill in Detroit

Four pin will give more comparable results. Two pin is much more dependant on probe condition, and contact with the wood, four pin - ideally - should not depend on this.

A sharp plug cutter, an oven at 100C for an hour, and a sensitive scale is of course the best way.

Reply to
Ian Stirling

It seems especially expensive because of the weakness of the dollar.

Reply to
Andy Hall

I am guessing, but do 4-pin meters work on the same principle as those BFI bathroom scales? Sort of "Does my beam look big in this" affair? ;-)

Reply to
Graham

True enough for planks. With the TDT (Turn, Dry,Turn) process, a moisture meter is absolutely unnecessary. The meter relies on continuous long grain, something not found in many places on a standard bowl form. The base or "foot" is the only place I can think of.

Better to stack such things to dry, pull when you think they should be, and then weigh them. If they weigh basically the same after a week, they're ready to turn. It's equilibrium, not absolute numbers that count.

Absolutes aren't even that important in flat work except as trend indications. If the hygrometer says the wood should be at equilibrium at

12%, and the meter shows 18, you need to wait. Of course you still follow good practice in construction, building loose with dry wood, tight with wet to accommodate seasonal changes. For me, in a heated home, that means 14% in summer and 6% or less in winter.
Reply to
George

You mean weight loss on drying?

Reply to
Aidan Karley

The basic theory of the two wire probes is similar to measuring the springyness of a spring, with two springy probes. It's hard to measure the springyness (resistance) of the spring, seperately from the probes, which tend to vary a great deal.

If with the four wire probes, you apply a constant tension with one set, and then measure with the other, you can get an accurate figure.

The body fat scales use a similar sort of idea - though they are designed to accurately -sort-of- measure the resistance of the thighs.

Reply to
Ian Stirling

...

formatting link
or
formatting link
(which is what I have, I use it to compare known "dry" with un-known)

Reply to
Ralph E Lindberg

A Wheatstone bridge?

Reply to
Graham

No, that's somthing slightly different. It would work if you could guarantee that the two feet pads made identical contact, but you can't.

formatting link
is a not very good article on it.
formatting link
may be more revealing.

Reply to
Ian Stirling

Works for me - actually a resister,two small alligator clips, two brads, a bit of wire and a multimeter.

Deb

Reply to
Dr. Deb

Try these for answers.

formatting link
formatting link

Reply to
George

Even at a 1:1 ratio, it would still be expensive for hobbyist use. I'm not going to get into a transatlantic whizzing contest, but simply note that I got mine (2 pin hobbyist grade) for about $40 .. not even 20 pounds. The only obvious lack is that it doesn't shut itself off.

If those on the far side of the pond think that ~150 pounds is an okay price to pay for a hobbyist grade moisture meter, then, by all means, be my guest.

Bill

Reply to
Bill in Detroit

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.