?An RC propeller actually works very well in water.? For decades the APC brand of RC propellers were the choice of human powered watercraft not only for high efficiency in low rpm water drive applications but because there was so many sizes and pitches to experiment
with.
Mike M
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From: k-designs@... <k-designs@...> on behalf of hanszilver@... [k-designs]
Sent: Thursday, November 23, 2017 12:25 PM
To: k-designs@...
Subject: [k-designs] Re: electric motor experiments
?
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Hi Bernd,
I actually also looked in these kind of things, but it seems the flex cable gives too much friction, and is probably not strong enough for a 400 Watt electric motor.?
I'm not sure why you think the RC propeller is not good. It works better than a standard prop (the spoed is 6 instead of 4 from a? trolling motor prop), being efficient at the cost of weed shedding and robustness.? For the tiny amount of power available
my?motor does well.
I think the problem with electric boatmotors is that the power (in a? small outboard kind of setup like mine)? is very limited. And if you use "normal" kind of power (say 2 Kw or more) you need big, heavy and? expensive
batteries. The electromotor itself is relatively inexpensive.
I have thought about a longtail kind of thing like you proposed in a private mail, but chose to use a simple, more or less standard setup because of the noise (motor not silenced under water) and the "lack of power unless
you? really go for it and buy a big batterie". The motor setup would then be more expensive as my whole boat, and that is not in balance.
Greetings from Hans
