Drawing and Thinking

I was doing a lot of drawing yesterday, literally all day sat looking at boat designs, making modifications. It was all extremely enjoyable and eventually I had myself a set of study plans, all to scale.

It, She, The Mastodon looks good, just exactly what I want from a boat. Cabin space, deck space, simple mast and rigging (er…), easy to build (um…), small and easy to handle….damn, I think I may have failed on those last three points.

Sure, you might think that 18′ is plenty small for a boat, but when you include the outrigger (ama) then it starts to get pretty heavy and unwieldly. Pretty much no chance of paddling it if I needed to, and that’s my measure of boat size. I have only ever handled a kayak before.

Mastodon has two masts and two rigs. This was fine in my imagination before I actually started to think about how to build them. It’s a lot of canvas, rope, battens and pole to be fitting. Furthermore, the setup involves stepping the masts to the keel. What that means is the mast goes through the deck and is attached to the floor of the boat. This would mean that the part of the boat that takes the most stresses would be 9mm from the sea. Even if I reinforced it at the base, that still leaves a hole in the deck. Simple enough I guess, but not as simple as possible. Plus I would need to do it twice.

Furthermore with the building complexity, Mastodon main hull requires 9 bulkheads. That is 9 perfectly shaped wooden boards that must cross the hull to give it lateral support. That doesnt include the actual prow either. Then I would need another 5-7 for the outrigger. The whole design also requires more than 500 sq ft of plywood, including ten complicated scarf joints.

The complexity is just going up and up the more I think about it. It’s not that I think myself unable to complete the project, but I am almost certain that it would be over time and over budget.

Simplification. I need simplification.

There are some more links at the bottom that helped. It took me until past 3am but I have a plan again. Meet The Mastodon 14′! (The name is getting less appropriate! Perfect.) Click for a higher resolution image.


The red shows 9mm plywood, the blue is 48mm aluminium scaffold and the black is a photoshop job of two front ends of ‘Paradox’.  This is actually my plan, ‘Paradox’ is a well proven design, it’s the right size, and I can easily buy plans for it.

I estimate that this boat will have an unladen displacement of 200kg! Means that by herself she will probably sit about an inch in the water. With myself, my stuff, food and a few other people she might get up to 500kg, which should have her sitting a mere six inches in the water. For people who don’t know much about boats, low displacement means speed.

The simplifications are:
1: 4 foot shorter. Means 3 fewer complicated scarf joints.
2: Deck stepped mast. Its now attached to the scaffold frame.
3: There is also only one mast and rig that does not have to make holes in the deck.
4: Because I am appropriating from plans, the bulkheads will have been designed for me.

The outrigger has been reduced in length by 2′ down to 10′. I am considering trying to make it less than 8′ so the sides can be just one piece of ply. That would reduce my scarf joint total to just 3! However the downside is that I would have to fiddle with some awkward angles on my scaffold crossbeams, come up with a different attachment method at the prows, or make the crossbeams out of different  material. Any of my options, be it 8′ or 10′ adds it’s own complexity, so I will just have to see which I dislike the least.

That pretty much solves all of the issues I had with the 18′ design. As you can see it is the same shape and has the same sq ft of accommodation. There is one berth on the lee pod and up two on the floor. Also in nice weather there is the option to sleep on the decking. Actual decking dimentions are to be confirmed.

So as I was saying, I had been growing more uncomfortable about my design. My “Aha!” moment came when I logged onto www.harryproa.com and www.sansboussole.com and began looking around.

The Harryproa designs and highly unconventional and I toyed about with making my own version until that complexity demon started creeping.

Sansboussole is another very interesting site about two French adventurers who have crossed the Atlantic with no instruments of any kind, solely navigating by the stars! It was their design of Micromega 5 that made me decide that my stubby little Proa would work.

So I am back on track with a cheaper and simpler design. If you have any boar know-how please let me know your thoughts in the comment section. Or if you know anyone who would be interested then please let them know.

Thank you for reading!


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