Tandem Drive.Outboard + Retractable Inboard.

Discussion in 'DIY Marinizing' started by tom kane, Feb 6, 2015.

  1. tom kane
    Joined: Nov 2003
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    tom kane Senior Member

    How do you think this combination would perform? Because boating in places where no one is available to help in case of motor failure or other trouble this unit was used.
    Use both inboard and outboard running together and using the outboard to steer.
    Running just the outboard with the retractable shaft drive lifted.
    Running the inboard drive and using the outboard not running to steer.
     

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  2. gonzo
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    gonzo Senior Member

    Outboards don't steer when they are not running. The drag of the propeller acts like a brake and not a rudder.
     
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    They do steer, a little. I have trolled off a small engine and used the big one (not running) to steer, but only in very wide arcs. You certainly could not manoeuvre is tight situations.
     
  4. whitepointer23

    whitepointer23 Previous Member

    That statement Is wrong. . Most people I know lock the auxillary straight ahead and and use the main outboard as a rudder when it is not going. Works fine. Beats sitting down the back steering the auxillary. Should try it before you say anything gonzo.
     
  5. tom kane
    Joined: Nov 2003
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    tom kane Senior Member

    Tandem drive + Retractable Inboard.

    As a shallow water boating fan the outboard was used as a rudder (no rudder for retractable inboard drive) not running and not fully down but at a small angle and not locked.
    The faster you went the more the outboard tilted and reduced drag as the outboard prop was mostly above water and only the outboard skeg trailing in the water.Less drag than a fixed rudder.
    This was more pleasant to use than a conventional rudder in most cases but was not very good for sharp turns at speed ( not much worse than ordinary rudder) but good in shallows. Increasing the area of the outboard skeg improved steering but was not convenient. Very shallow water use was the object down to about ten inches in mud and sandy shallows. Certainly better than any jet or other propulsion. And you did not have to rely on dynamic lift for shallow water navigation or speed.
     

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  6. gonzo
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    gonzo Senior Member

    Most people I know have the steering connected to both outboards when trolling so they can maneuver. I have tried it and doesn't really work. If the water was perfectly flat and there was no wind, you may do large arcs. However, that is not a setup where maneuverability is safe.
     
  7. tom kane
    Joined: Nov 2003
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    tom kane Senior Member

    Tandem drive + Retractable Inboard.

    My choice for family boating and camping in those beautiful places.
    Inboard retractable Pivotal Drive in tandem with an outboard because you can have the choice of two motors with the same ability to give a good speed to go most places and do it quickly with either motors to be in the right place at the right time. And you can run both motors to tow a less fortunate boat back to safety.

    A retractable drive inboard with a small auxiliary outboard come in at second because it is less easy to handle.
    Twin outboard means twin of the same problems as with all outboards.
    An stern drive is not a consideration because of weight, cost and complexity.
    With a retractable drive you can grind you way anywhere your boat will float and have no worry about replacing props as you can make your own out of steel plate and do any repairs which may arise yourself.
     

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  8. whitepointer23

    whitepointer23 Previous Member

    I agree about maneuverability but it definitely works to steer a boat home without having to sit at the auxillary tiller. I am not talking about connected steering.
     
  9. FMS
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    FMS Senior Member

    An advantage of two of the same is you only have to work on one technology with one set of tools for it.

    An aluminum alpha drive weighs approx 120 lbs, 80 lbs for the drive plus the transom assembly. It's the engine that is heavy and with the pivotal drive there is still the major engine weight compared with a lighter outboard powerhead.
     
  10. tom kane
    Joined: Nov 2003
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    tom kane Senior Member

    Thank`s FMS If you tried to run outboards or Stern drives, jets in very shallow water for a couple of miles it can be just about impossible and ruinous to the the units. Boats with deep v bottoms can not even float in 10 inches of water let alone work.
    We have tried just about anything you can think of to make life easy in shallow water boating.
    A Pivotal Drive shaft drive can weigh as little as 25 lbs as the boat it`self is part of the unit. The weight is in the prop shaft and prop and thrust brgs and rudder.
     
  11. slow fred
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    slow fred Junior Member

    Buy an air boat.
     

  12. tom kane
    Joined: Nov 2003
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    tom kane Senior Member

    Air boats do not go well on wet sand and water for miles all that noise and fuel expense the locals would be out with their shot guns and all the wildlife would never come back then the Harbor Master...
    and the Fisheries Officials would be wanting to arrest you for operating in a Reserve.
    The same applies to cushion craft etc., as these craft do not like logs and rocks catching on their skirts as do air boats.Just about two gallons of fuel for a three day trip makes sense. Now if you said buy a Ground Effect vehicle that would be acceptable if it was reasonable quiet and could just travel in ground Effect flight wherever I wanted to go and I would love that..I am trying..I am trying to do just that.
     
    Last edited: May 2, 2016
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