[Public-list] roller furling sail conversion

[Don Campbell]

Matthew and Mike;
    Sail shape is the main determinate of the driving force for a sail plan. The
greatest power is achieved with the foresail. I have just had a major problem
with a brand new 150 foresail, that I have been unable to trim to the shape I
have wanted when it is flying. It has not provided a smooth shape and has not
trimmed easily. Thus it has not had any power for the boat either. Since the
mian part of the driving force comes form the foresail, I have been very
disappointed. (I have even tried to have Towney solve the problem for me by
lending him the sail when he was here, and he made the comment that this was not
an easily trimmed sail and he did not like it,  but could not just put his
finger on the problem either.) The maker has been unwilling to come to look at
it on the boat,  so I have been at wits end to try to figure out where the
problem lies and have partially solved it with the maker on one hand, ( too
light a fabric)  and with help from my preferred sailmaker at Triton. After
pinning the sail to the loft floor, the arc on the luff was almost straight and
towards the head, almost inverted. Thus there is not enough material to allow
for a draft without creases in the foil surface.
    The decision to convert from hank on clips to a tape rather than buy a  sail
with a tape  for roller furling is one that I would suggest depends upon the
condition of the current sails. By that I mean how stretched the fabric is now,
compared to when it was new,  - most easily measured by the change in sail draft
depth and/or position. There may also be stretch on the luff length.  I would
suggest that when one rolls any blown out sail onto a furler to attempt to
reduce sail,  (which is not really what these units are designed for),  the
shape goes from blown out to worse,  regardless of whether the luff has had hank
on clips previously or has always had a tape.  Adding a foam pad in the luff
certainly increases the bluntness of the angle of attack, and is a performance
factor to consider because it will be there for 100 % of the sailing with full
sail, and worse when it is wound into any reefed sail luff. Since the  sail
shape is dependant upon the arc on the luff,  and if that arc is different
between the cut for hank on clips  and the cut for a tape for either roller
furling or a tuf-luff groove, I think you had better question what the sailmaker
is doing. The problem when one reefs using roller furling is that the arc that
is on the luff at the sail edge is not the same as the arc on the sail that now
becomes the leading edge where you stop for the reef. This forces an unnatural
shape into the sail and compromises both shape and performance. I reiterate that
these units are known as furling units not reefing units.
Don #528

Mike Lehman wrote:

> Matthew,
>
> I was faced with this same decision a few years ago when I too converted to
> a Schaeffer 1100 (nice system). I opted for a brand new sail rather than
> convert a hank-on to roller furling. With a converted hank-on sail the shape
> gets really bad as you roll it up. The more you furl the sail, the worst the
> shape becomes. Sails that are made for roller furling have a foam luff that
> helps keep the shape as the sail gets smaller (at least mine does). This
> does not mean you can go from a #1 to a "working jib" without loosing sail
> shape and performance, but it does mean you can go from say 150% to 135% and
> still maintain good shape. I bought mine from Bank Sails in Annapolis and
> have been happy with it. I have forgoteen the guys name, but he closed up
> the loft and I think went to work for North. For used sails, try Bacons in
> Annapolis.
>
> Mike Lehman
> ~~~_/)_/)~~_/)~~~
>
> ----Original Message Follows----
> From: "Matthew Hay" <haymatthew_ at hotmail.com>
> Reply-To: Alberg 30 Public List -- open to all <public-list at alberg30.org>
> To: public-list at alberg30.org
> Subject: [Public-list] roller furling sail conversion
> Date: Thu, 16 Feb 2006 18:20:34 -0500
>
> Matthew Hay #314
>
> I am installing a Schaefer 1100 series roller furler on my 1969 alberg 30.
> In your experience what is more cost effective: to convert an older hank-on
> sail that is in semi-good shape or to buy a new/used jib (perhaps larger
> then I have) that is already furler ready?  If the latter, where would you
> purchase such a sail  (preferably used to save money).
>
> Thank you very much.
>
> Matthew #314 "Renard"
>
> _______________________________________________
> These businesses support your Association:
> http://www.alberg30.org/store/A30supporters.html
> Please support them.
> _______________________________________________
> Public-list mailing list
> Public-list at alberg30.org
> http://alberg30.org/mailman/listinfo/public-list
>
> _________________________________________________________________
> Don’t just search. Find. Check out the new MSN Search!
> http://search.msn.click-url.com/go/onm00200636ave/direct/01/
>
>   ------------------------------------------------------------------------
> _______________________________________________
> These businesses support your Association:
> http://www.alberg30.org/store/A30supporters.html
> Please support them.
> _______________________________________________
> Public-list mailing list
> Public-list at alberg30.org
> http://alberg30.org/mailman/listinfo/public-list


 1140199478.0