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Checking-a narrow crack occurring usually at the ends of boards due
to shrinkage of the wood or excess exposure to sun and heat-can be a
very serious matter, especially on outdoor projects where water may
seep in. Exposure to hot sunlight may cause further shrinkage and extend the checking so that it may eventually split the board. If the
checking is severe, it is best to cut off the board as far as is necessary to
eliminate the checking. Then treat the ends with wood preservative before building it into your project. If checking is minor, filling the cracks
with waterproof glue mixed with sawdust will usually suffice to prevent
further damage. Work the mixture into the cracks well with a putty
knife. Fence post checks should be thoroughly brushed with a wood
preservative and, in addition, the below-ground parts should be well
tarred to fill all cracks and prevent decay organisms from entering the
wood. On the top of the posts, cap blocks an inch or more larger in all
directions will cover the ends and prevent further damage.
. . . measuring and ordering lumber
Ordinarily, lumber is sold by the board foot. While it is not really
necessary to know how many board feet you are ordering, the definition
of a board foot may be useful information to possess, because lumber
is priced according to the board feet it contains and your dealer will
sometimes figure it this way in billing you.
A board foot is a piece of wood 1 inch thick, 12 inches wide, and 12
inches long. Naturally, not all lumber you will be purchasing will be 12
inches wide, but it will be a portion of a board foot and figured and
priced accordingly. Let us take an example. Suppose you are using
2X6 lumber: each twelve inches of length will be a board foot. On
1X6 lumber each two feet of length will equal a board foot. Thus, a
2" X6"X 12' would equal 12 board feet, while a 1"X6"X 12' would equal
only 6 board feet.
. . . actual versus nominal size
To the novice, perhaps the most puzzling aspect of woodworking and
wood ordering is the question of "Actual Size" versus "Nominal Size."
In "the chart at the head of this section you will find a comparison of
these two sizes. You will use the Nominal Size in ordering and that is
what you will be billed for. This is approximately 3/8 inch greater than
the actual measure of the lumber in all pieces below 8 inches in width,
and 1/2 inch more than the Actual Size of lumber over 8 inches in width.
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