I've been thinking about a folding SOF expedition rowboat for quite a while now. I have a SOF folding kayak I made, thoughts around trying a rowboat are based on the idea that you can go bigger and wider once you're not restricted by the need to keep it as narrow as possible for a paddling stroke.
So, my design brief is:
Big enough to take two people, either both rowing or taking turns, big enough for one to sleep in at a pinch, big enough to put a (folding?) bicycle in. Still a good size for solo rowing. Small/light enough to tow behind the bicycle to the beach, pick up and get on the water on my own. Capable of being taken apart, put in a bag to go on an airplane, a bus, the back of a motorcycle or in a car boot. (No, I don't anticipate being able to fit the motorbike in this boat)
With sliding seat and outriggers. If possible as seaworthy as a sea kayak with a zip/velcro on fabric deck - i.e. capable of doing a multi day trip along an open coast. Reference point as to what is possible would be Colin Angus's row around Vancouver Island, though I realize that, as with a sea kayak, there's a lot of experience and acquired skill in managing a row boat or kayak along such coasts.
Very similar aims to what Colin Angus has already achieved with his rowboats, but lighter and fit in a bag capable.
I first fiddled with my kayak design making it bigger and wider, changing this and that, but was never happy with how it looked so I left it for a while. Some inspiration came from Dave Gentry's Ruth, I thought about a similar Whitehall with transom, just a bit bigger and wider? I had a play, but transom plus skeg or a wineglass transom started to look like too much of a pain in the butt to manage in folding SOF, so I went back to double ended.
A Norwegian Faering like Clint Chase's Drake or Iain Oughtred's Elf? Problem is, especially in folding SOF it's hard to maintain too much of that beautiful upward curving sheer line.
I finally spotted some pictures of the Finnish rowboats, those I saw were more like the picture I had in my mind - the right size, nice clean lines, chine and gunwale lines that can be bent from a stick, so I had another go at drawing. Results are here, still some fiddling to do, but I'm getting closer to being happy with the looks and lines than before.
6100 mm (20 feet) long, 1120 mm wide, so about the same size as a big double sea kayak. A bit more rocker at the front than the Finnish rowboats, but keel line reasonable straight at the back for a bit of a skeg effect. First chine moved out quite a way compared to the Finnish Rowboats, so less deadrise and a wider beam at the waterline for more stability and load carrying capability. Profile still reasonably low for less windage - I'll rely on a deck to keep the water out in rougher conditions rather than the upsweep at the bow and steer of the Faerings and Iain Oughtred's double enders.
It'll be some time before I can build it, in the meantime I'll work on a "virtual build", see if I can get all the structure defined in CAD with a view to getting the ply cross frames CNC cut and the plastic snap in connectors between the cross frames and the stringers done on a 3D printer I have access to.
More on construction methods soon in another post.