Re: Bowspirits
Thu, 6 May 1999 03:14:06 EDT

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West Wight Potter Website at URL
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In a message dated 5/5/99 9:56:05 PM Pacific Daylight Time, writes:

> I rather like the idea of picturing a Potter with a prominent
> bowspirit--and don't forget the nekid mermaid figurehead as well <grin>
> Judy B. what would that do to the sailability?
> Mary

Hi Mary,

Truth be told, I don't know what it would do to the sailability or rig
integrity. I presume you're considering moving the headstay forward and
that's what would affect the rig. I wouln't do that without careful analysis
or professional advice.

I've thought idly about it, in moments of greater-than-usual madness. I
kinda like the nekkid merMAN idea and the idea of keeping an anchor up there
(controlled in some magical way from the cockpit). It would also increase
the "J" dimension (from the bottom of the headstay to the mast) and permit me
to rig a jib-boom and a track for a self-tending jib.... but I think all
that is another boat, not my P19 :)

If all you want to do is add a bowsprit for mounting your mermaid, all you
need to consider is the load on the bowsprit. For hanging a mermaid, there's
no significant load.

But maybe you want to hang your anchor there. A bowsprit is usually
stabilized by a bowsprit shroud running to the masthead and a bobstay running
from the tip of the bowsprit down to the v of the hull below the bowsprit.
Now you're imposing loads on the mast if you move the headsail and torsional
forces on the bowsprit when you're at anchor. That would require a careful

If you're looking for a professional opinion about adding a bowsprit to a
Potter, you might pose the question on
<A HREF="">Spar Talk</A> , a
bulletin board run by a professional rigger, Brion Toss. (I have his book
_The Rigger's Apprentice_. It's interesting stuff) Perhaps Brion has
enough practical experience to give a seat-of-the-pants answer regarding the
feasibility of adding a bowsprit to a Potter class sailboat.

A sucessful rig is a balanced static and dynamic system, and if you change
anything, you have to be careful to preserve the balance of forces. Brion's
book has a chapter on calculating loads on stays and masts, figuring the
moment of inertia of a mast, etc., The math is somewhat tedious, I'm not
proficient in it yet and I'm not sure I ever will invest the time to become
proficient. I trust that Herb Stewart designed the P19 rig as a set of very
successful compromises and I don't stray too far from his desigh.

If you do install a bowsprit, let us all know and maybe I'll copy you. I'd
love to get my anchor out there and rig a self-tending jib, but I'm not brave
enough to be the first to do it.

But it might be easy enough to hang a nekkid merman there. You don't, by any
chance, know where I can buy a good-lookin nekkid merman, do you? : ^ )

Judy B

Judith Blumhorst, DC
HMS18/P19 Fleet Cap'n, Potters Yachters
1985 WWP19 #266 Redwing
Sailing on SF Bay, CA
(5-35 knot winds, 2-4' chop, 2-6' swells, and currents up to 6 knots)
Visit <A HREF="">Judy B's
West Wight Potter Pages
and <A HREF="">The Official Web Site of
the Potter Yachters