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Old May 26th 09, 11:43 PM posted to rec.aviation.homebuilt
Charles Vincent
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Posts: 170
Default Bamboo Propellers

Stealth Pilot wrote:
On Mon, 25 May 2009 12:32:15 -0500, Charles Vincent
wrote:
I know the British preferred mahogany for their propellers, but as I
recall, mahogany had some serious knocks as prop material. I can't
bring them to mind at the moment though.

Charles


mahogany was used by the brits, to quote lattimer-needhams engineering
text,
"mahogany is largely employed in the manufacture of airscrews, and the
variety that grows in honduras is favoured for that class of work. The
suitability of honduras timber is due chiefly to the fact that its
liability to shrink (after efficient seasoning) is only very slight
and that it possesses particularly satisfactory glue retaining
qualities. it is a strong, hard, straight grained wood and is not
difficult to work."


I found the reference. It was in Martin Hollman's Modern Propellor and
Duct Design book. It just notes that mahogany tends to splinter easily
and is therefore not a good choice. In any event, mahogany doesn't
grow here in Texas, at least anywhere near me. Bois dArc does though
and has ridiculous strength in compression - double mahogany (I have a
house built on Bois D Arc stumps, the tree is so ugly, termites won't
touch it) I have the compressive strength numbers since it is a common
foundation material, but do not have the normal engineering values for
the rest. I need to find them.

Charles