Andy Dingley writes:


[...]

One solution is to only use radial boards, which don't curve. In
medieval times this was done by splitting the tree rather than sawing
it (also easier work) to give very stable "riven" boards,
unfortunately wedge-shaped. Around 1900, the fashion was for

Which gives rise to the question why you never see boards made from
two suck wedge-shaped ones glues together to form a rectangular slab?

--
Dr. Juergen Hannappel http://lisa2.physik.uni-bonn.de/~hannappe
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Physikalisches Institut der Uni Bonn Nussallee 12, D-53115 Bonn, Germany
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