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Jim Richardson
 
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On 03 Sep 2004 11:57:24 GMT,
JAXAshby wrote:
jim, redefine any and all words you can to "prove" (to yourself and
any doubters out there) that your spending $2,200 for a prop to make
your boat go 1/10th knot faster was one hell of a smart "investment".


Why do you insist on claiming I bought an autoprop?

the word "feathering" can not be used in the context of a corkscrew
prop such as an auto-prop. except by "investers" mentioned above.


Then why did you post a definition of feathering, which fit the
autoprop?

an auto-prop is an auto-prop. the blades twist a little under high
power/low speed, twist a little differently under low power/low speed,
and twist something differently under no power/any speed. the drag on
the prop is still very high indeed (as a percentage) compared to a
genuine feathering prop. auto-props are sold (by the manufacturer at
least, if not always by the dealer) as a variable speed transmission.



Fact remains, the blades on the autoprop swivel to be inline with the
shaft, and present less drag than in the forward or reverse direction,
how is that not feathering?

keep in mind that props don't drag all that much anyway. according to
the MIT data, even a fixed 3 blade only pulled 170# on a boat at 5
knots, or about the equivelent of 2-1/2 hp.


Not relevent to the issue. It may mean that the autoprop wouldn't be
worth the cost, don't know, haven't bought one, don't plan to. Although
we will be replacing WindWalker's prop this next year, it's likely going
to be a fixed prop, simply because of cost. Some possibility of a
maxprop, but that's only if we think the cost is affordable.


--
Jim Richardson http://www.eskimo.com/~warlock
Does Emacs have the Buddha nature? Why not? It has bloody well
everything else