Subject: Re: [harryproa] Beam mounts and tillers |
From: "Rudolf vd Brug" <rpvdb@freeler.nl> |
Date: 3/10/2011, 5:34 AM |
To: |
Reply-to: harryproa@yahoogroups.com.au |
----- Original Message -----From: Rob DenneySent: Thursday, March 10, 2011 12:49 AMSubject: Re: [harryproa] Beam mounts and tillersRudolph,
Did it sail bow down with the old rudders? Was there any noticable
change in trim with the front rudder raised? Did it make any
difference upwind or down? Do the new rudders steer ok downwind?
Sorry about all the questions, but the more I know, the more able I am
to sort it out.
Ben,
There is no question it is sailing bow down and no doubt this affects
the steering. The question is why is it bow down? I suspect it is
because the rudders are turned at a big angle. The only other change
is the keel. If it is the rudder angle, the next question is why are
they at such an angle? Obviously a clr/coe balance problem. But if
you lift the front one (or align it with the flow), the coe is ahead
of the clr of the aft rudder which should provide lee helm. The keel
will influence this, not sure how much. If you reduce the sail area
aft of the coe (reef the main, the lee helm should be even more
pronounced. Apparently (Rudolph?) it wasn't.
I have found that once any of the boats are moving, the helm is pretty
easy (see the various videos). BD is the exception to this. The
time when it can be tricky to steer is coming out of a shunt. That is
when big rudders and no fixed foils work best, in my experience.
All very perplexing.
rob