I've had SOME luck in reversing the process--wetting the concave side to
expand the fibers, and aggressively drying the concave side. Reduces the
cupping, anyhow. The Furniture Doctor book recommended putting cupped
boards concave side down on the lawn for a few days. Let the moisture from
the earth hit the concave side and the sun bake the convex side.

Then you've got to sticker/anchor/weight the boards while they dry to
equilibrium so they don't jump back as they were. I don't know if that
induces some residual stresses that will show up when you use them.

It's a shame to waste all that fine wood, hope something works.

Another thought--is the convex side the bottom (unfinished) side of the
tread? Might be a chance of it flattening out when the unfinished side
dries to the same moisture content as the finished side.


Walt C



"Lars S" wrote in message
news:2005031311554816807%larsstole@gsbuchicagoedu. ..
I recently acquired over a dozen 42"x12"x1-3/4" white oak stair treads from
a rennovation site of a 100-year-old greystone. This would be a gloat,
except I already spent a day getting them from the construciton site,
pulling nails, and cleaning them off. And, the biggest problem, most of
them are significantly cupped from being exposed to a few onths of rain and
melting snow. The cupping is about 1/2" to 3/4" across the 12" width of
most of the treads.

Here's my question. If I sticker the treads for a while (how long?) will
the cupping reverse over time? If not, I can easily plane off 1/2" of
material and make some very nice, flat 1-1/2" boards (I'm thinking two
side tables and a matching coffee table), but I don't want the planks to
reverse-cup once I've made a nice table top. I'm a bit impatient, so I
would prefer not to wait a year to use the wood.