DIYbanter - View Single Post - Okay...I give...when WILL my pine table top quit moving??

wrote:
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I had the lumber acclimatizing in my shop for about three weeks. I
first rough-dimensioned it, then let that sit for another 3 - 4 days in
case it moved again. Finally, I four-squared it to its final
dimensions and glued it up.

Only to find that, after gluing-it up to near perfection (straight,
flat, I was damn proud!), ONE of the four boards has cupped AGAIN and
warped the tabletop.

Granted, I'm using crappy plainsawn knotty pine, but is that my only
mistake here?

It will stop moving about six months after you put it into an
chamber with constant temperature and humidity.

You can minimize movement by sealing it all around with shellac.

If one board is giving you a bigger problem than the others, and
it is not exposed more (or less) to the ambient atmosphere or
spilled moisture or some such than the others it is probably
what is technically referred to as a 'bad board'. Seriously
that particular board may be reaction wood cut from a leaning
trunk or maybe it has asymetrical grain or something.

If you replace that board and seal the whoel tabletop (sides top
and bottom) with shellac you may be happy with the result.

If you can find used bowling alley, a cheap solid core door,
or a small butload of used hardwood flooring you'll probably
be happier with those in the long run.

A number of people have had success with using Doug Fir for
their benchtops. The availabliity of Doug Fir dimensional
muber varies wildly. It is very rare and expensive in
Suburban Washinton DC, but 8' 2x4s in DOug fir used to
cost $3.50 each at Hechingers, when there still were
Hechingers here.

--

FF

to be not