Hi
I am not sure as to how to call you as you haven't signed your email
but hi anyway,


I have thought some similar things and discussed some of them with
Mark for the Harry I plan to build.
There doesn't seem to be any particular reason not to flare the ww
hull inwards except for ease of building but how much extra space do
you really get. I have wondered about having the dimensions of the ww
hull similar to a Farrier tri but the theory is to keep the
length /width ratio reasonably high to reduce wave drag. I am not
sure if Rob has tried a fatter ww hull to contrast it. These boats
can carry a fair load for their width and depth as there is very
little rocker. The limit of the ww hull on the Harry is largely due
to legal towing widths. There is actually quite a lot of
accommodation in these boats, especially for the weight and cost.
My idea for getting extra space in the cockpit and turning it into a
decent saloon is to put the sleeping areas sideways with the feet
under the outside seats. There is a problem of heel which has to be
addressed.
I also liked the idea of flaring the inside of the lw hull, a la some
of the Schionning designs, to both give extra accommodaton and also
to reduce the point loadings on the crossbeams but Mark pointed out
that there are added complications in the engineering for the torque
on the lw hull. There is also the interference with the rudders. I
still think it worth a try. There is already enough room in the
Visionarry for berths in the lw hull but the Harry is a little narrow
for comfort but possible.
Unfortunately, with extra accommodation the boat starts to get
heavier.
The lack of headroom on the bridgedeck is primarily to avoid
excessive windage but it is comfortable sitting down and you can
always put in a pop top for relaxed cruising and at anchor.
All these extra complications add to time and effort in building that
may be better spent on building bigger or finishing earlier and
sailing more.
Seeing these boats in the flesh gives a different perspective on
their roominess. I would contrast accommodation/weight ratios to get
an understanding of their value.


Robert

--- In harryproa@..., "jocroome" <jocroome@y...> wrote:
> Hi All,
>
> I have been researching multi designs to build for a while now
(Wharram, Woods, Kellsell,
> Shuttleworth & Farrier) and really like the Harryproa concept. It
just seems to me that there
> is not much space in them for their size. So I have a few questions
regarding their design.
>
> Why does the accommodation hull need to be so narrow down low?
Could a Harryproa be
> built with an accommodation hull like the centre of a trimaran, or
at least more flared.
> There would be little more wetted area, but bouyancy would be
improved as would living
> area inside. Is it because of slamming or wake interference between
the two hulls?
>
> The bridgedeck area from what I have read is not of standing head
room height. Could the
> height of the mast boom be raised to allow for more height in the
bridge deck or would
> this adversely affect windage and or righting moment?
>
> Could the lee hull be flared more at the top to provide more
useable bunk space when
> visitors are aboard or for crew if the boat were put to charter
work?
>
> Sorry if these have been canvassed before, it's just I couldn't
find the info.
>
> Love the designs, just love the simplicity, keep up the good work.