The timber is Australian Red Cedar, the insert is Birch. I used the insert as the design means approx. half of the storage compartment is in darkness.
As to the making, really no different from making a conventional bandsawn box, bandsaw the outer shape, cut two ends from the block, then bandsaw three sections following the outer shape, then glue it all back together.
(Given the interest in this design I am about to prepare a full sized Plan.)
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