IS BALSA THE LIGHTEST WOOD IN THE WORLD?
No! Most people are surprised to hear that botanically, Balsa wood is only about the third or
fourth lightest wood in the world. However, all the woods which are lighter than
balsa are terribly weak and unsuitable for any practical use. The very lightest
varieties don't really resemble wood at all, as we commonly think of it, but are
more like a tree-like vegetable that grows in rings, similar in texture to an
onion. It is not until balsa is reached that there is any sign of real strength
combined with lightness. In fact, balsa wood is often considered the strongest
wood for its weight in the world. Pound for pound it is stronger in some
respects than pine, hickory, or even oak.
SELECTING BALSA FOR MODEL BUILDING?
Most hobby shops have a large rack of balsa sheets, sticks, and blocks that
you can choose from if you are going to build a model airplane from scratch.
Undoubtably, because of the nature of balsa, the actual weight of each piece of
wood of the same size can vary slightly. When you select the pieces you want to
buy you should keep their final use in mind. Logically one should select the
lightest grades for the lightly stressed model parts (nose blocks, wingtip
blocks, fill-ins, etc.) and the heavier grades for important load bearing parts
of the structure (spars, fuselage stringers, etc.). To a large extent, this
selection is already partly done for you. Here at SIG, we purosely cut up our
lightest raw balsa into blocks, and our hardest raw balsa into sticks. Sheets
are cut in the entire wide range of density.
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