Building a trolling motor

Discussion in 'Propulsion' started by magnumcalib, Mar 12, 2011.

  1. magnumcalib
    Joined: Mar 2011
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    Location: Lansing, Michigan, United States, Eath, Milky Way,

    magnumcalib Junior Member

    First time posting here, hopefully this is the right place! Anyway;

    First off, I am building a small light weight Cateran/pontoon boat type boat (have a little bit of fun cash so I'm going to try my hand at building something) I got a good deal on a motor head (Link to the item on ebay) I am going to be attaching this so it is stationary on the stern of the ship (and will control it via a rudder) what I am asking you all here for is how should I control the actual throttle of this motor? It is off of a 5for.(3 rev.) speed motor and does not have the "grip". any suggestions are appreciated, thanks!

    Magnumcalib
     
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I'll let the others talk about speed controllers, but steering with a rudder is clumsy at best. You should steer with the motor, which is much more responsive.

    Lastly, a 45 pounds of thrust motor is about the same as a 1/2 HP outboard. Worse then this is the prop, which will prevent you from going over 3 MPH, even if the little motor had the guts to push you that fast.
     
  3. magnumcalib
    Joined: Mar 2011
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    Location: Lansing, Michigan, United States, Eath, Milky Way,

    magnumcalib Junior Member

    key isn't speed, this is more of a work boat. Short but can handle a bit of weight
     
  4. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    A 45 pounds of thrust trolling motor can barely handle it's own operational (batteries) weight.
     
  5. pistnbroke
    Joined: Jan 2009
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    Location: Noosa.Australia where god kissed the earth.

    pistnbroke I try

    well you were robbed on the price ..way too much for half a motor and no prop...dont run it out of water you will burn the shaft seal ... these small ones often run best on 24v ...just look up a speed controller on google and build a mosfet based controller for max efficiency ...

    otherwise \i agree with par ... slow and steady wins the race unless the current is against you ( at over 3 mph !!! )
     
  6. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Have a look at the size motors are fitted to similar size vessels to give you an idea. Electric motors are not really cheaper and require maintenance especially the batteries, heavy and expensive and continuous recharging.

    Fuel motors are not so expensive, it just sounds that way, but at least while you have fuel you have full power. The electric cannot offer the same amount of work as the fuel. Be patient, we're working on it ;)
     

  7. pistnbroke
    Joined: Jan 2009
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    Location: Noosa.Australia where god kissed the earth.

    pistnbroke I try

    looking at your photo you will find that there is a negative or common wire and a main thick positive wire ...the others are thinner resistive wires to vary the speed ( not efficient) ..you could easy connect a simple multi pole switch to move the pos from cable to cable and just spin it 180 deg for reverse...put some oil on the seal where the shaft comes out if you want to run it out of water...best is to use the oil seal expander fluid sold for leaking gearboxes and the like as it soakes into the rubber expands it 3 % and is a good lubricant.

    remember model aero propellers are the most efficient at the 1200 rpm you have ..about a 12 x 8 is ok.....get a strong one .

    look up the post on here ...efficient electric boat
     
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