Originally Posted by
tedsander
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There was a "fad" at one time to either cut out holes in the foam cores, in the balsa skins, or both to save weight. In my cases, the weight saving were very, very minimal, considering all the extra work.
Much of the small weight saving probably came from using less glue. I suppose it isn't necessary to have glue everywhere. Just a pattern that doesn't have very big gaps.
Elsewhere, difficulties getting very light balsa have been discussed. A popular solution has been to use thinner sheets of heavier and stronger balsa.