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Darrell Feltmate Darrell Feltmate is offline
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Default To Bag or not to Bag

I like to use Anchorseal on the endgrain outside of the bowl and let it dry
on a shelf.


--
God bless and safe turning
Darrell Feltmate
Truro, NS Canada
www.aroundthewoods.com

"George" wrote in message
. ..

"Dr. Deb" wrote in message
...
I just turned a piece of mulberry (about 11.5 x 6.5d) to rough shape and
have set it back to dry. I heard somewhere that it was better to put the
piece in a brown paper bag than to leave it just set out in the open air.

So, (with apologies to the Bard) "To Bag or not to Bag, aye, that is the
question . . "


It's all relative. Humidity, that is. If you have high relative humidity
right now, say 70% or better, even a nasty wood like mulberry could be all
right. If not, you might want to create a microenvironment inside a
container which will keep the relative humidity at or above that level
until the water has a chance to leave the wood for a while.

Paper bags are a particularly advantageous medium, because they're
basically delignified wood. As such they will adsorb water to roughly 30%
moisture by weight inside, and then lose it slowly to the outside air.
With a short distance for the water to travel, they aren't the same as
storing in shavings (dry, in my preference) or a bag of shavings. I like
cardboard boxes. Makes for a slow come-down. It's the differential
drying rate between the surface and the interior that you fear most. If
the surface doesn't check, there is much less chance that the checks will
grow to destroy your piece.

If you don't have one, buy a hygrometer. That's where the valuable
information lies. That, and
http://www.fpl.fs.fed.us/documnts/fp.../fplgtr113.htm chapter
three. Look at figure 3-3 for the direction of warp, and compare to your
piece. The curvature and annual ring interval are big determinants of
success.

I'm boxing everything at 40% RH right now.

Did I mention there's no such thing as a free lunch? Keeping the wood at
high relative humidity for fairly long can grow some ugly black mildew.
Spin the water out, blow it out, and don't bag until the surface looks dry
if you can't tolerate re-turning a lot of wood away.