I picked up a General MMD4E moisture meter at Lowes the other day, and was
curiously running around measuring the moisture content of various items
around our home. I'm sure this meter isn't the most accurate, but it does
give very repeatable results. Of course, this left me with more questions
than anything.

I always heard wood should be dried to 8% to 10% for woodworking.

My meter shows 12% to 14% for lumber (various species) that has been stored
indoors for over 10 years. In fact, I got that same reading from the
cabinets I have in the garage, wood trim around the doors, and even from
the sheetrock. How could I ever expect to reach 8-10 percent if everything
is at 12% to 14%?

Out of curiosity, I measured some "green" 2x4's I picked up today for a
remodel project and they came out around 14% to 16% on average too.

For that matter, measurements of my deck railings, and plywood siding came
out around 14% to 16%.

My seasoned firewood averaged around 16%.

The only wood I got a higher reading with was my rotting wood chopping
stump that registered around 30% moisture.

Admittedly, we have had a very wet spring here in the Pacific Northwest, so
maybe 12% to 16% is just to be expected?

Curious....

On 7/1/2011 8:23 PM, HerHusband wrote:

I always heard wood should be dried to 8% to 10% for woodworking.


My meter shows 12% to 14% for lumber (various species) that has been stored
indoors for over 10 years. In fact, I got that same reading from the
cabinets I have in the garage, wood trim around the doors, and even from
the sheetrock. How could I ever expect to reach 8-10 percent if everything
is at 12% to 14%?

In general, no significant dimensional changes will occur if wood is
fabricated or installed at a moisture content corresponding to the
average atmospheric conditions to which it will be exposed.

And basically that depends upon the part of the country you live in. In
the far Pacific NW you are not too far off averages, most likely within
the tolerances of the instrument itself.

Also pay particular attention to the type of wood and the recommended
calibration/offset for each type, which can really throw the reading off.

Check out this chart.

http://www.fpl.fs.fed.us/documnts/fplrn/fplrn226.pdf

Also answers some more of your questions:

http://www.fpl.fs.fed.us/documnts/fp...chapter_13.pdf

AAMOF, that whole series of government documents are a valuable resource.

--
www.e-woodshop.net
Last update: 4/15/2010
KarlC@ (the obvious)

Bake some wood at 250 degrees. Boil the water out =

Then try your meter.

Interior humidity can be higher than that depending on the
air conditioning and season.

Martin

On 7/1/2011 8:23 PM, HerHusband wrote:
I picked up a General MMD4E moisture meter at Lowes the other day, and was
curiously running around measuring the moisture content of various items
around our home. I'm sure this meter isn't the most accurate, but it does
give very repeatable results. Of course, this left me with more questions
than anything.

I always heard wood should be dried to 8% to 10% for woodworking.

My meter shows 12% to 14% for lumber (various species) that has been stored
indoors for over 10 years. In fact, I got that same reading from the
cabinets I have in the garage, wood trim around the doors, and even from
the sheetrock. How could I ever expect to reach 8-10 percent if everything
is at 12% to 14%?

Out of curiosity, I measured some "green" 2x4's I picked up today for a
remodel project and they came out around 14% to 16% on average too.

For that matter, measurements of my deck railings, and plywood siding came
out around 14% to 16%.

My seasoned firewood averaged around 16%.

The only wood I got a higher reading with was my rotting wood chopping
stump that registered around 30% moisture.

Admittedly, we have had a very wet spring here in the Pacific Northwest, so
maybe 12% to 16% is just to be expected?

Curious....

On Jul 1, 8:23*pm, HerHusband wrote:
I picked up a General MMD4E moisture meter at Lowes the other day, and was
curiously running around measuring the moisture content of various items
around our home. *I'm sure this meter isn't the most accurate, but it does
give very repeatable results. Of course, this left me with more questions
than anything.

I always heard wood should be dried to 8% to 10% for woodworking.

My meter shows 12% to 14% for lumber (various species) that has been stored
indoors for over 10 years. In fact, I got that same reading from the
cabinets I have in the garage, wood trim around the doors, and even from
the sheetrock. *How could I ever expect to reach 8-10 percent if everything
is at 12% to 14%?

Out of curiosity, I measured some "green" 2x4's I picked up today for a
remodel project and they came out around 14% to 16% on average too.

For that matter, measurements of my deck railings, and plywood siding came
out around 14% to 16%.

My seasoned firewood averaged around 16%.

The only wood I got a higher reading with was my rotting wood chopping
stump that registered around 30% moisture.

Admittedly, we have had a very wet spring here in the Pacific Northwest, so
maybe 12% to 16% is just to be expected?

Curious....

I buy quite a bit of hardwood from a SW Missouri hardwood mill and I
trust the owner. On more that one occasion he has told me he keeps
lumber in his kilns until it is in the 6% to 8% range. Then he racks
it so it can "start soaking up humidity". A lot of his racks have
wood in the 6% to 11% range. This is another reason why it is good to
keep some project wood in your shop for a while so it can acclimate to
your area. I am not comfortable with storing in my air conditioned
basement and then moving it to a warm, humid shop. Might be wrong,
but that's the way I work.

RonB

On 7/3/2011 3:25 PM, RonB wrote:

I buy quite a bit of hardwood from a SW Missouri hardwood mill and I
trust the owner. On more that one occasion he has told me he keeps
lumber in his kilns until it is in the 6% to 8% range. Then he racks
it so it can "start soaking up humidity". A lot of his racks have
wood in the 6% to 11% range. This is another reason why it is good to
keep some project wood in your shop for a while so it can acclimate to
your area. I am not comfortable with storing in my air conditioned
basement and then moving it to a warm, humid shop. Might be wrong,
but that's the way I work.

Nothing wrong about that, in fact it's smart.

A very important proviso to wood movement which is often overlooked:

"In general, no significant dimensional changes will occur if wood is
fabricated or installed at a moisture content corresponding to the
average atmospheric conditions to which it will be exposed."

CITE: http://www.fpl.fs.fed.us/documnts/fp...chapter_13.pdf

IOW, within a roughly 2% swing in moisture content, there will be no
significant movement at all.

--
www.e-woodshop.net
Last update: 4/15/2010
KarlC@ (the obvious)

On Jul 3, 3:42*pm, Swingman wrote:
On 7/3/2011 3:25 PM, RonB wrote:

I buy quite a bit of hardwood from a SW Missouri hardwood mill and I
trust the owner. *On more that one occasion he has told me he keeps
lumber in his kilns until it is in the 6% to 8% range. *Then he racks
it so it can "start soaking up humidity". *A lot of his racks have
wood in the 6% to 11% range. *This is another reason why it is good to
keep some project wood in your shop for a while so it can acclimate to
your area. *I am not comfortable with storing in my air conditioned
basement and then moving it to a warm, humid shop. *Might be wrong,
but that's the way I work.

Nothing wrong about that, in fact it's smart.

A very important proviso to wood movement which is often overlooked:

"In general, no significant dimensional changes will occur if wood is
fabricated or installed at a moisture content corresponding to the
average atmospheric conditions to which it will be exposed."

CITE:http://www.fpl.fs.fed.us/documnts/fp...chapter_13.pdf

IOW, within a roughly 2% swing in moisture content, there will be no
significant movement at all.

--www.e-woodshop.net
Last update: 4/15/2010
KarlC@ (the obvious)

The only thing I think about is we live in SE Kansas within 70-80
miles of the Ozark dealer. In fact we are both pretty much in the
Ozark weather pattern - wet!. When I store in my garage and build a
project it ends up in and air conditioned home. I think about it but
I have never had a problem.

About 10 years ago I built a couple of heavy tables (coffee and
end)for our son and both had 8/4 Red Oak tops. The Coffee table has
butcher block ends that are free to slide with expansion of the main
table top. And slide it does! He also lives in the Ozarks and is air
conditioned but also a tight a** Irishman. He runs his summer
thermostat in the 78-80 degree range. We visit from time to time and
I always check the table width with regard to the block ends. Since
the Oak doesn't move much in grain length, there is usually a little
variance in match. Sometimes the slab is a little proud of the end,
sometimes, usually winter, it is even or vice verse.

Not earth shaking info, but kind of neat to watch wood movement in
action. also the reason I attached top to frame with wood slide
blocks.

RonB