Most recent version of this craft is shown top, earlier versions are shown below. Some things of note,
a relatively simple layout.
Optimised for single person sailing.
Daggerboard is low aspect ratio, and tilts back to aviod damage on grounding.
Trailering beam is 8ft
Lots of decked in space, relatively little open space, making swamping not a critical issue
A nice comfortable cabin forward for protection from the elements
This is more a refined version of my present boat
Crossbeams are aligned with full width bulkheads for structural integrity
This craft is really too heavy to be dragged up a beach single handed.
Changing to a pivoting centerboard and kickup rudder is an option if lots of beaching is anticipated
This is an early tentative attempt at designing a camp cruiser. The idea is to get a boat that is comparable to some of the lightly built long and narrow skiffs that are often used for camping out for 2 or 3 days
The above hullshape was derived from the 3SD banks dory from Hannu Vartalia. I made the transom more vertical to assist in fitting conventional rudder mountings. I then scaled up the hullshape to provide more interior volume. I only did the above sketches on 17 March 2009, so it obviously still needs a lot more refinement. From start of sketching to what is seen here took approximately 90 minutes, so thus there is still a long way to go until this is up to standard
One thing of note is that the above sketches drawn in 90 minutes from start of finish were based on a requirement for a double berth. This results in a flat low main hull which is not ideal for a mulithull as it will go over waves as opposed to through them. In many respects it would behave much as my present 18ft boat does in that it would work well in modest conditions but tend to pound if forced to go to windward in steep choppy seas. Now if the users only intend on going out on fun orientated relaxed weekends in sheltered waters then this boat would do well.
Next we look at a similar setup but with improvements, and also with the double berth requirement dispensed with, what would that look like. To start with I worked on center section. I took the publicably available sketches of the Tremonlino midpoint cross-section and stretches the horizontal axis by 50 percent to increase space. Funnily enough the resulting shape looks exactly like the cross-section as depicted by Skip Johnson and his P52 proa. So that gives a good starting point.
I moved the forward crossbeam aft so that it is less likley to impact waves. I have shown a sliding mechanism with a strut. Retracted beam is 7ft 8" and extended beam is 10ft. This is a little under the P52 proa but that is a longer boat and logic suggests that beam/length ratios should remain relatively constant. The board goes into the cockpit. It is a daggerboard that rotates on grounding, this method is a combination of the ideas of Dick Newick on his Tremolino trimaran and the work of Joe Dobler and his Lissa skiff. Because the board is a fraction aft, the mizzen sail needs to be increased in area. It may be that the foot of the main hull needs to be a fraction deeper and narrower in the coble style in order to get the center of effort forward enough so that it corresponds with the center of effort from the sail plan.
Of the above 2 endview sketches, if the horizontal sliding crossbeam method, with the crossbeams placed at gunnel level as per the P52 proas was followed a workable setup would be obtained. The downside is that the retracted crossbeam would slide directly into the cabin interior. Possibly this is no great inconvenience, as cabin will of course be empty whilst being trailered. Thought may need to be given to keeping this point watertight in order to keep occupant dry. Lastly below find a few doodles of a hinged version whilst retaining the high mounted crossbeam.