We're in danger of straying rather a long way from the point. With a sea mileage somewhere in excess of six figures (gallantry prevents me from saying how many decades this has been spread over), Annie has a very clear concept of what kind of boat she is happy to live on, and what kind of boat she can build, and afford to build, and she has laid down a clear list of her requirements.  The task she has set us is to design a boat that covers as many of those requirements as we can manage. 3 tons of displacement, on a LOA of 26ft and a LWL of say 22ft 6in, gives a very wholesome and live-able D/L ratio of around 260. A longer boat at this weight would be more lively than is desirable, as a permanent home, and would require a higher tech structure than Annie wishes to build and than she wishes to afford.

Now that I have Freeship to work with, I've been able to model the hull and deck, and check some of the figures for my design:

Length over all : 7.958 [m]
Beam over all : 2.962 [m]
Design draft : 0.510 [m]
Midship location : 3.980 [m]
Volume properties:
Displaced volume : 2.968 [m3]
Displacement : 3.042 [tonnes]
Total length of submerged body : 6.950 [m]
Total beam of submerged body : 2.502 [m]
Block coefficient : 0.3346
Prismatic coefficient : 0.5733
Vert. prismatic coefficient : 0.4931
Wetted surface area : 13.501 [m2]
Longitudinal center of buoyancy : 3.938 [m]
Longitudinal center of buoyancy : -0.610 [%]
Vertical center of buoyancy : 0.336 [m]
Midship properties:
Midship section area : 0.745 [m2]
Midship coefficient : 0.5837
Waterplane properties:
Length on waterline : 6.950 [m]
Beam on waterline : 2.502 [m]
Waterplane area : 11.802 [m2]
Waterplane coefficient : 0.6786
Waterplane center of floatation : 3.708 [m]
Entrance angle : 7.579 [degr.]
Transverse moment of inertia : 4.148 [m4]
Longitudinal moment of inertia : 30.165 [m4]
Initial stability:
Transverse metacentric height : 1.734 [m]
Longitudinal metacentric height : 10.499 [m]
Lateral plane:
Lateral area : 2.558 [m2]
Longitudinal center of effort : 4.230 [m]
Vertical center of effort : 0.296 [m]
Approximate weight of hull and deck 0.851 tonnes

Sectional areas:
| Location | Area |
| [m] | [m2] |
|-----------+----------|
| 0.950 | 0.096 |
| 1.900 | 0.371 |
| 2.850 | 0.622 |
| 3.800 | 0.747 |
| 4.750 | 0.671 |
| 5.700 | 0.473 |
| 6.650 | 0.161 |
| 7.600 | 0.000 |
|-----------+----------|

Robert Biegler wrote:

Annie Hill wrote:I like to be able to tack instantly when I'm headed in a confined area and there is no way I want to play with a balance jib.  I can see the appeal of a proa, but not for me.

Well of course, make a suggestion of your own: this is what the Sib-Lim Challenge is all about!!

I find it doesn't meet your requirements.  I was thinking of a monohull proa, stabilised by a foil to windward instead of a hull.

PS. Yey, finally the WA editor  works with Chrome/Android! 

I received this as part of a Christmas message from a Dutch friend:

That might just be appropriate for JR design. 

David Tyler wrote:

There are the hydrostatic calculations to do, and the bow needs to be modelled, virtually or as a hard model, as I can't be sure of exactly how the shape should be, on the basis of the 2D drawing.

David

Have you considered a 'pram' bow?  Makes for easier construction and fits nicely with the 'Chinese' aesthetic.

Peter S

Copper on the bottom is not in the running? Expensive initially, but then no more buying bottom paint… And the five panel hull would make copper sheathing so easy!

Shemaya