On Sunday June 23rd my friend Kevin and I took the Chameleon to Lake William for it's first trial since the gearbox failure of last summer. There have been a few changes since then.......
I had the original gearbox switched from 2:1 to 1:1 because I was concerned about reliability. Well this boat was designed to be used with one or two riders so when it came time to make up the drive train for the second rider I chose to buy two new gear boxes and went with 5/8 shafts and 1:1 ratio. I will use the other box for the single hull version. Each drive system is completely independent of the other and installed on a 2 x 2 tube with the gearbox on the inboard side of the tube. From there a 10 foot aluminum shaft goes back to an airplane prop with the only support being a 1/16 wire to a small steady bearing. (which could and will be smaller at some point) The wire is just to stop the shaft and prop dragging on the bottom when pedaling stops. It is also a way to lift the prop free of the water when not pedaling and to clear weeds, lobster pot lines etc. The shafts are both turning clockwise when viewed from the stern so that they tend to move in the same direction when getting on and off the power. The props are also designed to turn in one direction only. Plus, the shafts are different lengths to reduce the chances of them hitting each other.
There is a spring loaded idler wheel on the chain which has a limiting bar so that the drive train can be pedalled in reverse. One prop is a 16 x 14 and the other is 16 x 12 right now.
The frame has been lengthened one foot and an extra set of anchor brackets has been added to both hulls. The two piece deck is cedar and is now only as wide as the frame without the extensions. I had grand plans about having enough deck space for a carnival, hot tub, and float plane but........things are heavy enough as it is!
I made two seats from aluminum tubing and covered them with red mesh. The blue is just temporary!!!
The rudders are raised and lowered by the levers on both sides of the deck and I can reach them both if I am using the boat on my own and sitting in the middle. The steering control uses wire in a plastic jacket and is set up so that it can be moved depending on the number of people pedaling. The left rudder is always connected and the right one is only to be hooked up for sailing or rough water.
So on Sunday morning the boat was fully assembled on the shore and carried to the water, clearly this thing has been eating well over the winter because it is a LOT heavier than the ideal...........Anyway, we paddled away from shore and dropped the props in while the boat was drifting, I started to pedal and it felt like the boat felt like something was dragging on the bottom......I looked back and realized the prop was turning the wrong way and we were in reverse!!! At some point I got the gearboxes on the wrong side doh!! An easy switch and off we went again, this time it worked well. It was quickly evident that we were going to have to come up with a way to increase the rpm of the prop because the boat was certainly not at full speed when we were pedaling as fast as possible. But everything worked okay and the props did not hit even during hard turns.
Things needing attention,
I have made two 90 tooth props to replace the 52s on there now. Much cheaper than replacing gearboxes etc. Also made two fixtures to go in the ends of the frame extensions with 12 inch wheels on them so the whole boat will be easier to manage, plus I can move it myself.
The method of raising and lowering the rudder works well but the steering is unsatisfactory. Too many lines and shackles etc and the steering effort is too high. I can do things to make it a bit more efficient but I am thinking about doing it using hydraulics. Single action cylinders could be built quite easily, double acting are more work but certainly possible. Plastic cylinders, stainless rods, plastic lines.....More complication but a fun little side project....
At some point the seat mounting brackets will have to be made easier to adjust but will do for now.
Tomorrow I will get at least one mega sprocket installed ( don't have another crank with the appropriate offset at the moment ) and now I am just waiting for a break in the rain to try it again!
