cordless drill powered boat racing

[sam_uk]

From what I have read the larger model aeroplane propellers are good for canoe sized boats.

 

[Even Chance]

From what I have read the larger model aeroplane propellers are good for canoe sized boats.

Yes you are absolutely correct. They are long and thin and apparently the most efficient shape for these low RPM/High thrust applications. Ive researched this for a while now before commiting myself to making a unit.

I spent this weekend playing with the idea. I sandwiched the Dremel flexi drive between two 18mm plywood side pieces. I then added the 11x5 (11" diameter x 5" pitch) plastic prop from my .40 size model planes, and the 16.8V (4s) Lipo powered battery drill to the top end.

I went down to the marina and jumped on the Mirror Dinghy, clamped this contraption to the stern, and proceeded to take a run round the harbour powered by said contraption. It showed a max speed of 2.3 knots, and reached this speed very quickly indeed. This shows that there is ample thrust, but I could maybe do with some more pitch speed. I also have 10x6 and 10x8 props to try yet to get more pitch speed.

The Dremel shaft cant take the torque developed, so I will buy some bevel gears at 1:1 gear ratio, and use them in the MK2 version. Its certainly on the right track though.

 

[Warpdrive]

After you have enjoyed the cool canoe challenge videos check out this video of long tail boats racing in Tiland
http://youtu.be/bKzyLIonf0c
Amazing stuff and not one crash on video .

 

[Daydream believer]

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