[Public-List] Best prop?

[Michael Connolly]

Jonathan,
Is that 3000 rpm of the engine or prop?  3K for a diesel is kinda high, is it not?
Michael
> On 06/19/2024 10:27 AM EDT Jonathan Bresler via Public-List <public-list at lists.alberg30.org> wrote:
> 
>  
> When I got Constance #262 in 2015, the boat had installed a
> 3 blade 12RH14 propeller that worked very well with the
> Yanmar 2GM20F and its 2.62:1 gear reduction box.
> 6kts at 3,000rpm.
> 
> Jonathan
> 
> 
> 
> 
> 
> On Wed, Jun 19, 2024 at 9:57 AM Pier-Andre Bouchard St-Amant via
> Public-List <public-list at lists.alberg30.org> wrote:
> 
> > I understand. I would not have undertaken such task if Jean-du-Sud already
> > had an aperture.
> >
> > You can however reduce the featherstream size to fit a standard apterture.
> > Which size is best, then, is a question for someone else.
> >
> > Fair winds!
> >
> > Pier, #399.
> >
> >
> > --
> > Pr Pier-André Bouchard St-Amant
> >
> > Bur.: +1-514-849-3989 #3923
> > Cell.: +1-514-424-6632
> > pabsta.qc.ca <http://pabsta.qc.ca/>
> >
> > > Le 19 juin 2024 à 09:38, John Johnston via Public-List <
> > public-list at lists.alberg30.org> a écrit :
> > >
> > > Thanks, Pier for the prompt and very informative reply. Changing the
> > aperture size to accommodate a larger prop is an interesting approach, and
> > perhaps one I will pursue in the future while hauled out. What I am seeking
> > right now is an off the shelf prop that will work best within existing
> > limitations of the aperture. I don’t want to miss another Summer not
> > sailing, and I don’t have the time ( nor the heart) to do more than a quick
> > > haulout and install.
> > >
> > > All the best,John
> > > Sent from my iPad
> > >
> > >> On Jun 19, 2024, at 8:51 AM, Pier-André Bouchard St-Amant via
> > Public-List <public-list at lists.alberg30.org> wrote:
> > >>
> > >> Hi John,
> > >> I used a 13" featherstream 3 props on Jean-du-Sud. Here for the model:
> > >>
> > >> https://www.darglow.co.uk/featherstream/
> > >>
> > >>
> > >> Here for the original calculations:
> > >> https://en.jeandusud.com/repowering-an-alberg-30-part-1/
> > >>
> > >> The biggest downside of this model is the price. The upside is reduced
> > drag.
> > >>
> > >> Upon purchase, they will adjust the blades' angle to the most efficient
> > angle at peak power. You can adjust the angle at a later time, or ask them
> > for an angle specific to your calculations (peak power at low rpm, etc)
> > >>
> > >> I would pay attention to the propeller size and the rudder max
> > availlabe size while in a full turn (on both sides). That is also an
> > implicit limit on the propeller size.
> > >>
> > >> Best,
> > >>
> > >> Pier, #399
> > >>
> > >>
> > >>
> > >> Le 19 juin 2024 08 h 36 min 09 s HAE, John Johnston via Public-List <
> > public-list at lists.alberg30.org> a écrit :
> > >>> Hello folks, especially those Alberg owners who have diesel engines -
> > Can you recommend a 3 blade prop that is suitable for the aperture
> > limitations? The 14” height calls for a smaller prop to be effective-
> > >>> Thanks!
> > >>> John Johnston
> > >>> Alberg 69
> > >>> Sent from my iPad
> > >>> _______________________________________________
> > >>> These businesses support your Association:
> > >>> http://www.alberg30.org/store/A30supporters.html
> > >>> Please support them.
> > >>> _______________________________________________
> > >>> Public-List mailing list
> > >>> Public-List at lists.alberg30.org
> > >>> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
> > >> _______________________________________________
> > >> These businesses support your Association:
> > >> http://www.alberg30.org/store/A30supporters.html
> > >> Please support them.
> > >> _______________________________________________
> > >> Public-List mailing list
> > >> Public-List at lists.alberg30.org
> > >> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
> > > _______________________________________________
> > > These businesses support your Association:
> > > http://www.alberg30.org/store/A30supporters.html
> > > Please support them.
> > > _______________________________________________
> > > Public-List mailing list
> > > Public-List at lists.alberg30.org
> > > http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
> >
> > _______________________________________________
> > These businesses support your Association:
> > http://www.alberg30.org/store/A30supporters.html
> > Please support them.
> > _______________________________________________
> > Public-List mailing list
> > Public-List at lists.alberg30.org
> > http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
> >
> 
> 
> -- 
> Jonathan M Bresler
> S/V Constance Alberg 30 #262
> Annapolis/Eastport MD
> _______________________________________________
> These businesses support your Association:
> http://www.alberg30.org/store/A30supporters.html
> Please support them.
> _______________________________________________
> Public-List mailing list
> Public-List at lists.alberg30.org
> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org