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Jeff Morris
 
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I'd have to agree that there are good and bad props. I'd also agree that
reverse performance is not necessarily poor with a good folder. I have two
Volvo folding props on my catamaran and I've had little problem in reverse. But
then, I have two diesels and the boat is under 10,000 pounds.

On the MIT/Practical Sailor test for reverse thrust, the Gori ranked somewhat
better than the Martec folder, but substantially worse than almost all of the
other props. At a given rpm, the folders only had a third to a half of the
thrust as the fixed props that were tested. I suppose there could be a fixed 2
blade that's worse than the Gori, but its pretty clear there are some that are
much better in reverse.



"Lauri Tarkkonen" wrote in message
...
In "Jeff Morris"

writes:

I'd agree with some of your conclusions, especially that a folding prop is
perhaps not useful for the OP's Westsail. Since a 2-blade fixed can be lined

up
in the aperture to minimize drag, there's little reason to sacrifice reverse
capability with a folder. I can't imagine trying to "crash stop" a Westsail
with a poor performing prop.



There are good props and bad props in folding and unfolding category.
A good folding prop is better on reverse (and thus in stopping) as a bad
fixed prop. I have tried it, when I lost my folding prop (GORI) and had
to settle for a fixed one with equal diamerer and pitch. Wit my folding
prop there was never any trouble in reversing or stopping the boat, the
fixed one could not get me out from a berth against a 25 knot breeze.

- Lauri Tarkkonen