: those are good articles... though they seem to be more concerned with
: resistance and speed more than I am...
: but, my line of thinking was this: if I take a conventional design as a
: starting point, then alter it to make it more suited to fishing rather
: than just paddling, what effect would it likely have on stability.
: I suppose it would be easy to make a highly unstable boat!
: If I took a design and shortened it, then widened it - what would that do to
: stability. if I lowered (my) center of gravity - would it help.
: does a square stern really affect anything? and so on?
: any opinions?
Speed doesn't mean fast. It usually means the speed a particular hull is most efficient at. For higher speeds, a longer, slimmer hull is better. For lower speeds, shorter, wider hulls. Ther are upper and lower limits to this, where the increase in one type of drag exceeds the benefit of the decreasing other type of drag.
Shortening and widening a conventional design would increase its initial stability somewhat, but not all that much over the original. The entire hull provides stability so widening a hull would increase its initial stability in proportion to the change in beam. Shortening that hull will decrease its initial stability because there's less hull to resist heeling. You can end up with the same level of stability you started with.
Lowering your center of gravity in a canoe is always good, but you still have to get your paddle over the gunwale comfortably.
The effect of having a square stern varies with how it's is done. The Ridge River seems to just have a square stern at the gunwale level with a normal canoe stern, presumably to mount an outboard. This would have no effect on the water drag as it's all above the waterline. However, to support the weight of a motor, the hull has to be wider aft than usual.
Most canoes are fairly ok for fishing, a neighbour of mine uses his 14-15 foot canoe for rod fishing. He just casts sitting down. It's a generic plastic canoe.
How short do you want to go? How wide? What class of water do you plan on using the canoe on? How far do you intend paddling to get to the fishing area? The answers to these is a good and necessary starting place for starting a design.
Hope this helps,
South West Cork