Building A Boat - Page 10 - The Return Of The Snow Pea
By Mike on Sunday, September 6, 2009, 22:43 - Permalink
September 2009: Owing to the conspiracy of a number of different factors in my life and circumstances, I'm ashamed to say that the Snow Pea languished in my garage not only for the winter of 2007, but for the whole year of 2008 and most of the summer of 2009.
However, this is about to be remedied...
I've cleared out a lot of the clutter that was preventing me from even taking down the boat from its hanging position, and more importantly, I've done some work to try to correct what I think is the major remaining flaw - directional stability.
The Problem
It might just be down to lack of familiarity with handling, but I did find it just a little difficult to keep the boat tracking in a straight line - the reasons for this are, I think, twofold:
- A short hull, and with the upswept ends, an even shorter length in contact with the water
- The outrigger - effectively increasing the width of the boat
A Proposed Remedy
I'm going to add a long rudder - it will be a steering rudder, but I anticipate using it primarily in non-steering mode - that is, just to keep tracking straight
The rudder post is made from a sandwich of thick waterproof ply tongues, affixed to a reclaimed maple centre
Strong vine eyes are driven into the maple to act as one half of the hinge mechanism
The counterpart vine eyes are driven into the stern post and the assembled mechanism is held together by a large bolt
It swings freely through almost 180 degrees. Later on, I will add some elastic cords to keep it centred unless otherwise deflected.
The rudder blade is a long piece of waterproof ply in a rounded triangular shape
It will be bolted in place between the two protruding tongues of the movable rudder post - swinging on a single bolt, the rudder will be able to flip up if it strikes an obstruction or when the boat is beached (as opposed to just breaking off otherwise)
The blade will be sprung into the downward position by elastic cord and pulled up by hand using a short rope handle
Steering will be effected either by a pair of lines attached to the rudder horns, or by a rigid pole attached to one of them
A Turning Point
If you'll pardon the pun, the addition of this rudder marks a turning point for the Snow Pea...
If It Works
If it works, I will spend the winter equipping the boat with a small mast and sail (can't really do sailing without a rudder anyway) - as well as some sort of leeboard.
In the early summer of 2010, I'll transport everything to a suitable area of safe, calm inland water and see if I can teach myself to sail (I fancy I understand the basics, but recognise there's a difference between theory and practice)
If It Doesn't Work
If after the addition of a rudder, the Snow Pea is still too hard to handle, I will draw a line under it all - dispose of it and start again - building another, simpler boat from an established, stable design.
25th Sept 2009 - It's all done (pics to follow soon) everything is set for a test launch this weekend - I plan to be down at Botley Quay about 3pm on Saturday 26th to test out the new rudder modifications...
26th Sept 2009 - Here's a picture of the finished rudder assembly - in the end, we used it in this upper position all the time - it didn't need dropping any further and would only have snagged on weed or submerged branches
A long curved pole is attached to one of the rudder horns, curved (laminated from two pieces - the same as the outrigger pylon supports) - the curve allows the front seat passenger to steer - going around the person at the rear
Pushing on the pole causes the rudder to flip to the right and pulling it does the opposite
Directional Stability
The rudder makes as significant an improvement in directional stability as the outrigger did to general stability - it's easy to track in a straight line and very responsive in turning
It's even possible to paddle on the side opposite the outrigger and set a slight bias on the rudder so as to still go in a straight line
Handling the boat on my own is now tricky, although I think this could be overcome by fixing the rudder control pole so I can lock it in any given position - I'd still be able to effect a turn by braking with the paddle
What Next?
Well, there might be time for a proper trip down the river in the warm days of Autumn... we'll see...
My project for the winter will be the construction of a sailing rig and leeboard - I plan to make this as yet another bolt-on module
In fact, I'm starting to like the idea of bolt-on accessories for the Snow Pea- I also have in mind (longer term) a pedal-power option - either driving a paddle wheel or a screw propeller. I will use chain drives or some other method to direct the rotary power up and over the gunwale, so that there is no need to perforate the hull