A 22 1/2 foot Cruising sailboat design

There are many excellent programs available now to help you design your own boat. It's much easier than when I first looked into doing this nearly 30 years ago. The main tool I have used is FreeShip plus. This is a boat design tool that is totally free and open source. It is powerful but unfortunately a bit buggy and crashes regularly (so save often!). However it allows you to design a multi chine plywood hull and generate plots of the plywood panel shapes that you can use to build the boat. This last feature is invaluable if you are working in plywood and want to make a hull where you can fiberglass tape/epoxy the whole thing together using the stitch and glue technique.

Here are some initial plans for my boat:

Lines plan of the proposed boat

The first picture shows the boat from the side, back, front, and overhead. Not shown is the centerboard and skeg below the waterline. The design is similar to a stretched simplified Welsford Penguin.

Side view showing windows and other interior details

One of the really useful features of modern boat design CAD software is the ability to view a 3D visualization from any angle. I made a short video of rotating one view of the proposed design.

It will be a while before I begin construction of this but I have printed out templates for the plywood sheets that make the outside of the hull and the interior supporting bulkheads at 1:12 scale (1 inch - 1 foot) to test out if it looks OK in 'real life'. I tried to assemble these using cereal boxes and light bristol board with limited success but I did confirm that the boat will likely come together from the dimensions that the CAD software produces.

One of the really fun things about the design process is learning stuff that you would not normally be aware as a sailor or even a boat builder. For example how does one determine how stable your design is. Where should one should locate the mast to help avoid excessive weather helm, and what shape and size a centerboard should be. I have learned that most boat designers when creating a design begin with a proven similar design rather than completely starting from scratch. One piece of advice I see on boat design forums is to have a look at what has worked before and start there. Good advice!