Martin,
You are correct. The folding propeller is much more sensitive to the
orientation of the pin to ensure the blades fold correctly. Having a blade
hanging down is probably the equivalent of dragging your foot in the water.
At 5 knots, this can represent a fair amount of force. Even with bad
orientation, the blade will eventually be forced to fold, but will still
create some drag.
My shaft is marked so I can easily tell the pin orientation. The port
locker is empty, except for a boat hook and scrub brush. I used to climb in
and move the shaft by hand, but lately I just grad the boat hook and use it
to rotate the shaft collar.
Jake
Jake Brodersen
C&C 35 Mk-III
Midnight Mistress
Hampton VA
-----Original Message-----
From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Martin
DeYoung
Sent: Friday, August 09, 2013 9:18 PM
To: cnc-list@cnc-list.com
Subject: [SPAM]Re: Stus-List [SPAM]Re: transmissions in gear while sailing
I believe the shaft / prop pin location is more important with folding
propellers than feathering propellers. For long races (like Transpac) the
orientation of a two bladed feathering prop would be monitored.
For long offshore races on boat equipped with the non-geared folding props,
just before the start on of the crew would dive over the side to place
rubber bands around the blades to hold them closed. With two bladed MAX
props the shaft would be aligned with pre marked lines indicating the prop
was lined up with the strut.
Calypso has a three bladed MAX prop and we do not make any effort to align
the shaft. Maybe I should look into marking it to put one of the three
blades behind the strut for those light air days.
Martin
Calypso
1971 C&C 43
Seattle
-----Original Message-----
From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Indigo
Sent: Friday, August 09, 2013 5:55 PM
To: cnc-list@cnc-list.com
Subject: Re: Stus-List [SPAM]Re: transmissions in gear while sailing
Jake
I have never thought about rotating the shaft so the blades are vertical. I
had sort if assumes that once feathered, the drag would be the same
irrespective of position. You must also keep a lot less junk in the
lazarette than I - making it easy to access the shaft!
I do know that I will often shut down the engine while in neutral and then
start feeling the vibration from the spinning prop. At that point I just put
the transmission in reverse and the vibration stops. I have always assumed
that the blades would feather at that time.
--
Jonathan
Indigo C&C 35III
SOUTHPORT CT
On Aug 9, 2013, at 20:20, "Jake Brodersen" <captain_j...@cox.net> wrote:
> Jonathan,
>
> I position the prop to the blades are both retracted (i.e. the pivot
> pin is
> vertical) before we start racing. That way both blades are fully
> retracted for the lowest drag. I ran into a situation this summer
> when we were motorsailing. I shut down the engine, but the prop was
> still free wheeling at about 7 knots. I dropped the transmission into
> reverse. The prop stopped rotating, but I wonder how good this is for
the transmission.
> Maybe I should have shut down the engine in forward instead.
>
> Jake
>
> Jake Brodersen
> C&C 35 Mk-III
> Midnight Mistress
> Hampton VA
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