Rudder propeller drives?

Discussion in 'Surface Drives' started by OCB, Sep 2, 2016.

  1. OCB
    Joined: Dec 2015
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    OCB Junior Member

    turning

    I read they have poor slow speed turning in harbor for #1. If it has no down falls,why do they not come on all boats? They have less moving part then a out drive.
    I have looked for surface drive where just prop turns and trims at the end of the drive. Did the sea sled have a rudder propeller?

    Thank you,

    OCB
     
  2. gonzo
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    gonzo Senior Member

    If you have twin surface drives with trim and rudders, they turn on the boat's length.
     
  3. tom kane
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    tom kane Senior Member

    Rudder propellers

    There is no rudder on the drive I posted there is a skeg to protect the prop but you do not need that if you don`t want to protect the prop from damage.

    The drive can give 30 degrees of steering from side to side (like a stern drive) and also up and down which a stern drive can not do.. And obviously a thrust bearing on the prop shaft.
    There is a shroud that can be fitted to make a surface drive safer for family boating.
     
  4. mydauphin
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    mydauphin Senior Member

    I had a very fast boat one time, we'll capable of 80 knots. It had one major problem, idle speed was like 15 knots. In order to get in a out of canal and be able to maneuver we fitted an electric trolling motor to the back, it worked great for all kindness of docking, an kept all the angry people happy.
     
  5. Barry
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    Barry Senior Member

    Price
     
  6. OCB
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    OCB Junior Member

    Surface drive 15 Knots idle speed

    Is it doing 15 knots due to high idle speed HP motor or the drive?

    Thank you,

    OCB
     
  7. OCB
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    OCB Junior Member

    Surface drive price

    Is this the only thing you don't like?

    Thank you,

    OCB
     
  8. tom kane
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    tom kane Senior Member

    Rudder propeller drives

    http://www.gerrmarine.com/Articles/SeaSleds.pdf

    jpg Hickmans sea sled.jpg
     
    Last edited: Sep 4, 2016
  9. OCB
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    OCB Junior Member

    Turning prop with sea sled design?

    Do you think a shaft out the transom with single screw inboard motor like the sea sled will work on a larger boat?
    Is that the best hull design for this type of design?

    Thank you,Tom

    OCB
     
  10. mydauphin
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    mydauphin Senior Member

    A combination of several things; boat was very light, draft was zero, high idle race motors 1000 rpms idle, very fast props, and no steering below certain speed either. It was 27 feet with 400 hp inboards. It also did not like shifting back and forth. I crashed low speed twice into boats at marinas getting fuel.I was very young and stupid, bought this boat from sheriff sale. It was an ex-drug carrying boat. I found this out after the Coast Guard stopped me l4 times for searches. The last time they even took me to the station and opened holes in floor. I asked base officer for explanation and he told me boat was on list. Go figure. Anyway going 70 knots in Biscayne Bay was fun, if ridiculously dangerous. It was somewhat legal then. I was always running out fuel too. 120 gallons did not take me far. Oh forget boat had surface piercing props and a gizmo on drives like a wing to keep drives in the water.
     
  11. mydauphin
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    mydauphin Senior Member

    Any boat with twin props, you use throttle and shifting to move around at slow speed. With surface drives, reverse is usually the problem. Consider a bow thruster for turning. A rudder should be as small as possible to avoid drag. Putting propellers on it makes drag worse. Have seen race they barely have rudders. Big ships that travel slower have bigger rudders, they need them, and can afford drag.
     
  12. OCB
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    OCB Junior Member

    Great input. I will try it with no rudder. If i want better low speed handling. Maybe a pop down rudder mite help?

    Thank you,

    Ken
     
  13. powerabout
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    powerabout Senior Member

    cant wait for a production boat builder to use a surface drive instead of sterndrive due to all the advantages of a surface drive.....
    been waiting 30 years+...
    crickets...
     
  14. tom kane
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    tom kane Senior Member

    Rudder propeller drives

    Why have you waited so long when you could have built your own 30 years ago?
    But do not get too excited about surface drive you may change your mind and wish you had a drive that can be used in S/P mode or common old subsurface drive which is the more pleasant mode for family boating.
     

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  15. powerabout
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    powerabout Senior Member

    because I drove several 30 years ago and said, ok sterndrive or outboard for me and shaft drive midmount to waterski
    A bit like jets, they have 3 very specific uses:
    1. up rivers in NZ
    2. Jet ski's
    3. high speed ferrys

    I think the time and money will be better spent on azimuth drives for all sizes such that you can remove them in the water and either have electric or shaft powered or both.
    That would be a product to beat an IPS and ZEUS drive
     
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