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Jeff Jeff is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 1,301
Default Useless propeller

Thom Stewart wrote:
Oh Boy,
a lot of double talk, off topic rambling, lord knows what amount of
nonsense theory and yet no explanation of why a 2 blade propeller is
useless.


I have two folding props and for ordinary weekend warrior heavy
weather there is no problem. However, in situations where the boat
can surf down large seas and achieve speeds greatly in excess of the
intended prop range, the water pressure will try to close the props.
However, in these cases you ordinarily would not be relying on the
engines. I've had it happen on two occasions, once when crossing Lake
Ontario with the mast down - it was downwind with 8-10 short chop
behind us and we were surfing up to 13+ knots. The other was also a
following sea - 8-10 foot swells on the beam with with 6 foot chop
from the 25+ wind on the stern. I ran the engines to make it easier
to control while reefing (my crew was quite under the weather at this
point) and again found that surfing would make the props act funny.

In cases where we've had to power against large waves, we don't
achieve the speeds that would cause this problem.



I don't know why a 4 blade fixed is a better propeller for a sail boat
(S) Guess I never will (g)


I thought this was a quiz. Why are you asserting that a 4 blade is
"better"? BC was just trolling with his post - he really has no idea.


So, rather than be a PITA, I'll retire from
this discussion.


You give up too easy.


I'll discuss Middle East Politics with my Dog. At lest we'll stay on
TOPIC (G)

Signing Off




http://community.webtv.net/tassail/ThomPage