Reply by Gary Fixler

  • Advertise with us

Posted on Does wood shrink lenghtwise when drying?

View Gary Fixler's profile

Gary Fixler

1001 posts in 3893 days

#1 posted 05-28-2009 11:45 PM

Joe – I have both of Hoadley’s books (the other is “Identifying Wood”), and they are great. He’s a scientist from MIT who specializes in the science of wood. He knows his stuff!

As for bowing of wood, this is almost non-existent in woods that are quartersawn. Here’s a handy graphic. Riftsawn is even better, but rare, because so much wood is wasted. In these boards, the growth rings are more or less perpendicular to the face of the wood, so each side is essentially the same. In plain or flat sawn lumber, you usually get one side with much more open growth ring separation than the other, and longitudinal contraction of even a small amount pulls one side tighter than the other.

In Hoadley’s books, and in all the other places I’ve read, longitudinal swelling (remember, boards also swell back up when moved to more ‘moist’ environments!) and shrinkage is considered a non-issue. It’s not entirely true, but the figures I’ve always read are 0.1%-0.2%. Still, I suppose it’s always good to build for it, just in case. Things like mortises, and floating panels give some room for things to shift a little without tearing projects apart.

-- Gary, Los Angeles, video game animator

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics