I’ve written a few posts about my homemade, pedal powered boat but what I haven’t done is describe the many tribulations along the way. I’ve twice had wheels break on the trolley I use to get the boat to the water. I’ve tried 4 different ways of propelling the boat and, I think, 3 rudders. On most occasions I’ve curtailed my trip because a fault has occurred somewhere in the mechanisms. I’ve twice had to take the boat out of the water because of faults, transporting it on the fragile wheels to get me back home. It’s little wonder I named the boat “Perseverance”.
It has been a long project, beginning in January, but I’ve mainly enjoyed the process of developing something novel. Today things went swimmingly and no, I don’t mean that I had to swim! The hull was water tight from the start, it was just everything else which failed. This time, though, I went down to the 127 mile long Leeds/Liverpool canal, sailed for 40 minutes or so and returned home without a problem. Nothing broke, bent, deformed or twisted. No nuts or screws came loose and nothing fell off. In my earlier efforts I had greatly underestimated the strength and solidity which the components would need to withstand the power I could generate through my legs. Actually it’s not the power but the torque or turning force. I can easily push with way more force than my body weight in kilogrammes and by multiplying this figure by the length of the lever which I’m turning, in this case the length of the pedal crank, I will get the torque. Harley Davidson motorcycles are noted for their high torque figures and the highest output of any Harley is 131 lb feet. If I press my approx. 6 inch pedal crank with an easy to achieve 100 kg force the torque at the axle will be 110 lb feet. Fairly close and, interestingly, the same torque figure given by the new 1,250 cc model!
I’ve toughened the paddle wheel axle, strengthened the pedal system and replaced the rods which connect the 2 together with a far more sturdy option. It’s worked! I sailed further towards the city of Leeds than ever before (though it was still over 80 miles away). The pedals rotated smoothly with non of the annoying notchy feeling I’ve experienced before. Perfection! Or as near to it as I could expect in not just a home made boat but the first boat I’ve built. So now it’s going well what should I do with the boat?
Sailing along at walking pace isn’t the type of excitement I get from my other pedal powered vehicles in the form of mountain bikes. Sailing along the canal is a much more gentle activity. It’s less aerobic as a form of exercise but it does work the muscles quite well. I’m thinking that an endurance activity would be best so I need to make a more comfortable seat! I’ll give some thought to a suitable challenge.