Three rudders, three screws.

Discussion in 'Propulsion' started by Kun2112, Oct 22, 2010.

  1. Kun2112

    Kun2112 Active Member

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    Has anyone ever run this setup before? I am looking at building an O class battlecruiser this winter for Treaty and have been thinking about trying to run all three rudders off one servo using differential steering on the outer two as shown here www.rcnavalcombat.com/Forum/tabid/5...fault.aspx (page four of the thread)
    I am thinking about looking for an extra long double horn and running the center rudder rods on the bottom side of the horn, halfway out and putting the outer rudder rods on top of the horn at the ends.
    Does anyone have any input into my proposed method?
    Am I mad? Should I just get a Y harness and run two servos?
     
  2. Kotori87

    Kotori87 Well-Known Member

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    My Spahkreuzer had three shafts and three rudders. They were linked parallel, with one tiller connecting the servo to the central rudder (perpendicular to the centerline), and three tillers (one per rudder) linking the three rudders together. This setup kept the rudders parallel at all times, but Spahkreuzer could still out-turn any warship on the pond.

    I'm not sure how well the differential steering will work with your proposed setup, though. The pictures you linked to show the tillers overlapping each other, which you cannot do when you have a third rudder in there. I say go for it, but be ready to modify you design or even link them parallel if necessary.
     
  3. NickMyers

    NickMyers Admin RCWC Staff

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    Sounds complex. Assuming your rules allow it, I would link them up parallel but angle the outside rudders out a few degrees. It'll increase your drag going straight slightly (just like the drag discs do but to a lesser extent) and it will give you an effect close to what you are looking for.
     
  4. Kun2112

    Kun2112 Active Member

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    Line drawings here: s11.invisionfree.com/shipbucket/ar/t1966.htm
    Actually, I had an I dea at work today... Taking two horns, and connecting them with spacers on the inside holes where one is directly above the other, then drilling out the center "collar" on the top one to allow the screw and drive to pass through...
     
  5. froggyfrenchman

    froggyfrenchman Well-Known Member

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    I have never seen it done before. But it sounds like it should work. And I look forward to seeing how it works out.
    I do think it would be a great ship. And I hope that you build her.
    Mikey
     
  6. Tugboat

    Tugboat Facilitator RCWC Staff Admiral (Supporter)

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    Dustin, do you have a frames drawing for the O-Pro?
     
  7. Kun2112

    Kun2112 Active Member

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    Clark, I am just at the planning stage right now. I haven't gotten anything for the build yet--I need to tweak my Richelieu first.
    I have found some plans online that are in 1/350 for the ribs and 1/700 for everything else - them actually being in scale are very suspect at this time.
     
  8. Kun2112

    Kun2112 Active Member

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    So the Stike Models plan set shows the outside rudders at a slight angle: about 5-10 degrees off vertical. This will add some additional complexity to what ever I decide to do. I need to finish my Kongo class forst though...
     
  9. froggyfrenchman

    froggyfrenchman Well-Known Member

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    The H-39 rudders are also angled out.
    But it appears that we will install them straight up and down to keep things simple.
    Mikey
     
  10. WaterSide

    WaterSide Member

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    Are all 3 screws rotating in the same direction? I know with larger boats 1 screw operates in a counter clockwise rotation , being a rookie I dont know if it makes any difference. for these boats.

    Phil
     
  11. glaizilla

    glaizilla Active Member

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    One of the outboard props turns opposite of the other two props.
     
  12. glaizilla

    glaizilla Active Member

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    The Hindenburgs rudders are now angled outboard as shown in plans, the overall turning radius has changed very little, but the time in which it took to come about, has been reduced significantly.