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Dead slow ahead....

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  • Dead slow ahead....

    I've been working on the side on a brushless conversion of a "target" that I've run with the brushed setup. (Dumas Dauntless, with Dumas 12v pittman motors). I note that the slowest possible rotation speed of the brushless motors is considerablly faster than that of the brushed motors. Now, this isn't an issue with a go-fast, but on something scale I'd rather be able to just tick the prop over and idle along. I note that the brushless MSD is the same way, the slowest possible speed of the motor is still fairly fast. Until I get the target and the 688 in the water and gain some experience, this is just an academic observation and comment, and it's not like I expect to be jockying a 60" long single screw submarine around a dock...
    "It does not take so many words to speak the truth" Chief Joseph

  • #2
    Originally posted by a1965l View Post
    I've been working on the side on a brushless conversion of a "target" that I've run with the brushed setup. (Dumas Dauntless, with Dumas 12v pittman motors). I note that the slowest possible rotation speed of the brushless motors is considerablly faster than that of the brushed motors. Now, this isn't an issue with a go-fast, but on something scale I'd rather be able to just tick the prop over and idle along. I note that the brushless MSD is the same way, the slowest possible speed of the motor is still fairly fast. Until I get the target and the 688 in the water and gain some experience, this is just an academic observation and comment, and it's not like I expect to be jockying a 60" long single screw submarine around a dock...
    https://www.bing.com/search?q=coggin...lvar=0&PC=MSE1

    I agree with your observation. The brushless motors don't like the lower end of the RPM curve. And when very slow do a lot of cogging as the armature poles stutter past the rotor magnets. But, in-water, with the added torque load of the running gear and water, that should burden the motor enough to produce you're silly-slow turning wheel.

    Stop over-thinking this ****er, and get it in the water!

    David
    Last edited by He Who Shall Not Be Named; 05-29-2020, 09:58 AM.
    "... well, that takes care of Jorgenson's theory!"

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