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 . . "
BTW, I have used LDD but always had shrinkage and warpage. I tried soaking
for 24 hours, 48 hours, no difference, still warped.
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
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.
I turn Mulberry often, and it can be a real challenge to keep it
together, even when bagged.
Crotch, tension wood and wood with knots would be better boiled, IMO.
Also use a recess rather than a tenon, the extra wood in the foot likes
to split, so keeping it thinner helps, and yes bag it, it is the first
couple of weeks that you have to try to really slow down the drying,
after that you could place it just on a low shelf.
I do check my bags every couple of days at least in the first week and
keep the CA handy, if anything looks like it might split I will put the
glue on it, the glue will be turned away when finish turning, the same
applies to mild cases of mildew.
Have fun and take care
Leo Van Der Loo
I tried bagging a few times, and it didn't yield any better results
than air drying. Of course, the relative humidity here (Oregon) is
high. In the winter, especially with difficult woods, and when I
actually have a heater in the shop, I will put the fresh bowls almost
on the floor. After a week or so, they go up on a shelf. The exhaust
for my air scrubber/filter will blow on the blanks if I aim it there,
and I am in a bit of a hurry, but never on fresh bowls, I can even dry
Madrone this way. I do turn to final thickness, and let them dry and
warp. I don't think I have ever turned thick, let it dry and then