Hollywood wrote:
> Really? I didn't think a 28 footer was that bad.
Well, I didn't say it was *bad* it's not a practical approach to getting sailing. If the goal is to
build a nice boat, then a 28 footer is likely to be more economical and attainable than a bigger one,
sure. Building a 28 footer from scratch is likely to take less time & money than say restoring an old
10-Meter starting with just a battered hull...
> The one I'm looking at is a Mark Smaalder's
> design called a Wynfall.
Not familiar with it... any links?
> You can buy tupperware by the ton here but wooden boats seem to be in very short supply.
heh heh heh think about the reasons for that. It ain't that wooden boats are beeing carefully hoarded
by the Secret Elitist Sailor's Bund. I was going to suggest that if you really wanted an old-fashioned
boat, that there are a fair number of early fiberglass models that would suit you and provide an outlet
for plenty of labor... and you could go sailing in the meantime. Say a Cape Dory or Allied, or an older
(pre-1970) Pearson or Islander.
> ...
> finding a boat in the classifieds is just a little daunting.
It's no picnic finding one in the real world, either. The internet is a tremendous aid in sorting out
the chaff. I happen to like Yachtworld and Boats.com which both have good screening search functions.
You can select only boats in a give area, of a given material (aluminum, wood, fiberglass, ferrocement,
whatever you fancy) and of a given vintage. If the pickings are too slim you can always widen your
search.
A problem is that the type of boat you are looking for is the type that is least likely to be listed on
the internet (although it is freakin' 2004, almost *everything* in the world for sale is listed on the
internet!) so calling around to brokers and boatyards may yield some prospects. I happen to enjoy
driving to boatyards and poking around the back lots, my wife indulges me a lot but oddly enough her
enthusiasm wanes after a bit. We found our current boat on the internet.
>
> >The diagonal is supposed to show that the body plan is "fair" ie a smooth continuous surface,
> >hopefully capable of having planks laid along it without humps, shoulders, or needing to steam the
> >planks to the rigidity of week old spaghetti.
> >
> Now how does it show that? Is the diagonal at 90 degrees to the frame at that point?
Not necessarily. Some are.
> I guess
> that's what is confusing me. The buttocks are parallel to a line along the length of the keel
> and the water lines are parallel to a plane at the base of the keel and perpendicular to it,
> but what is the source of the diagonal? At what point does it show me a fair hull?
It's not at a point, it's along a line... or more accurately, it is the plane intersection with the
hull along a non-normal axis. ANd this is exactly what you need to know if you're going to try & lay
planks along the thing.
It may be easiest to consider an already built hull. Let's take a long springy batten and lay it along
the hull... we'll hypothesize some extra long arms and extra hands to do this, keeping the batten in
contact with the hull at all points...
We can lay the batten parallel to the waterline at any place from garboard to keel, and the ends of the
batten will poke out past the stem & transom. We can lay it parallel to the centerline, so that the
ends poke out above the gun'l, this would be the buttocks. Now let's hold the batten at a skewed angle,
somewhere between the axis of buttocks & waterlines. We are using an already existing hull, so of
course it lays along smoothly. **BUT** if you are considering a hull that is nothing but lines on
paper, you don't know that yet! It is quite possible to draw a set of hull lines, frames & waterlines &
buttocks, that look great in these three axis but form ungainly humps or hollows, or even
discontinuous, along a skewed axis... and this will make it very difficult to plank. A smart designer
will lay out a set of diagonals to avoid this, and the smart boatbuilder lofts these diagonals as a
check on his mold stations.
I just finished lofting a 9 1/2 footer, and did two diagonals. It was a PITA... but I did tweak the
lines a little bit and it'll be better & prettier because of that.
>
> >Bend the frame tight against the inside of a set of ribbands.
>
> ?!? Shows you where I'm at. I was under the impression that the frames were bent on molds, then
> placed inside the ribbands.
You could do it that way, but usually there are more frames than mold stations. Setting up the molds,
then laying on ribbands, then bending in the frames, allows more frames than stations. Also putting the
frames on the molds would create an offset from the hull plan to the hull skin.... most designers draw
what they want the hull to look like, not the shape of the inside of the frames. Designs intended for
wood construction often provide for "to the inside of the plank" which of course would be on the
outside of the frames.
>
> Actually, I must be denser than lead because I have been reading Chappelle as well as Larry
> Pardey (now that's the kind of boat I'm talking about) and while they both talk a lot about
> diagonals, they don't really explain where they are getting the information to lay it down or
> where the staring points are
Hmm, I don't have a copy of Chappelle handy right now but IIRC he covers diagonals about as well as
anybody ever has. The starting points are given along the base line for the hull lines plan. The
diagonals are dimensioned in the table of offsets and laid down with the rest of the lines.
FWIW there are a number of Lyle Hess designs similar to Seraffyn and Taleisin that were built as
production boats. They are usually pretty expensive unless in very crappy condition.
Fresh Breezes- Doug King<!-- ~MESSAGE_AFTER~ -->
>> Stay informed about: Diagonals in lofting 
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