No experience in canting rudders. Except on echelon model new geometry. The rudders and leeward ama are precanted to anticipate heel angle while under sail. Same with Geoproa model to a different degree.
Todd
--- In harryproa@yahoogroups.com.au, Gardner Pomper <gardner@...> wrote:
>
> Todd,
>
> Are you speaking from experience with canted asymettrical rudders? I keep
> wanting to build ones like what you have shown in your videos of your
> daysailing proa, but haven't gotten to it yet. They don't look like they
> "rake" (thanks for the correct terminology, Rob).
>
> - Gardner
>
> On Fri, Sep 9, 2011 at 12:22 PM, tsstproa <bitme1234@...> wrote:
>
> > **
> >
> >
> > Like what Rob said. Keep them vertical while sailing at optimal speed
> > range. Canting only if your trying to create negative or positive lift.
> > Sweeping rudders fore or aft to me is to much of a hassle. changes flow over
> > boards and forces felt in tiller. The less you have to deal with the better.
> >
> > Symmetrical vs Asymm. Asymm will bite sooner and harder grippier more lift
> > more drag. Symmetrical run free'er and not so forgiving to aoa changes less
> > bite less lift less drag ,better at higher flow rates.
> >
> > That's just the general notion.
> >
> > There's alot more to it than What I'm capable of explaining correctly.
> >
> > I'm thinking a more toned done asymm foil now. Just to see where it goes
> > from there. 6%/12%, 5%/10% balanced proportions instead of my 0%/10%
> >
> > Todd
> >
> >
> > --- In harryproa@yahoogroups.com.au, Gardner Pomper <gardner@> wrote:
> > >
> > > Rudders continue to be my main concern on the harrys. I am enamored of
> > the
> > > asymmetrical setup that Todd has demonstrated on his proa daysailer, but
> > I
> > > am also concerned about the instability issues that theory seems to
> > predict
> > > on the rudders (from Tom Speer and others).
> > >
> > > My question is what effect it would have to cant the rudder a small
> > amount,
> > > while keeping the axis of rotation vertical. Does this effect the
> > stability
> > > at all (plus or minus)? How would it effect the lift? I don't seem to be
> > > able to come up with a thought experiment that would give me a clue about
> > > what effect, if any, this would have. Does anyone know something that
> > would
> > > help predict this?
> > >
> > > - Gardner
> > >
> >
> >
> >
>