Rudder Removal Problem

Discussion in 'Sailboats' started by MMNet SEA, Jun 21, 2007.

  1. MMNet SEA
    Joined: Feb 2007
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    Location: Thailand

    MMNet SEA Junior Member

    48ft Steel 35 year old Dutch built Ketch.

    Conundrum , Please help,

    In reverse collided with ???
    Steel Rudder is now miss-aligned 15° with the quadrant.
    here are pics of the problem :-
    At the top of the rudder the shaft from the quadrant is held in place with a
    single nut - cannot see how this nut is retained once tightened up ?
    Once the shaft enters the top of the rudder - is it tapered ? Is it keyed ?

    How to Remove ?
    Here are a pix to illustrate :-
     

    Attached Files:

  2. Frosty

    Frosty Previous Member

    It looks as though the nut should be removed and then the shaft pulled up into the boat leaving the rudder to jiggle out of its lower bearing /support and off.

    It should be tapered and keyed yet if not could be the cause of your misallignment.

    If the shaft is tapered then it would be tight in the rudder. I would drive wedges inbetween the shaft and the rudder of the nut access hole.

    Are you sure this is all necessary? I would think the quadrant woud be the weakest link to take a reverse hit.

    It looks like you are at the boat Lagoon? Are you?
     
  3. MMNet SEA
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    MMNet SEA Junior Member

     
  4. alan white
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    alan white Senior Member

    Compare the diameter of the shaft top and bottom---- if the same, probably no taper. It would then be a straight key. I would cut the nut away with a die grinder/1/16" wheel rather than force it. It may be that the threads were purposely munged (hammered flat) to ensure the nut would stay on. Add some crevice corrosion, and that nut will be a bear to remove.
    Guess is the key sheared, but at least that would mean the shaft isn't frozen in place any more if it was.

    Alan
     
  5. MMNet SEA
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    MMNet SEA Junior Member

    Hello Alan,
    Thanks for the feedback, Unfortunately one cannot see the shaft as it enters the top of the rudder - nor is one able to see its diameter before it is threaded for the nut. So the question regarding taper and keyway remains unanswered.
    Do not want to cut the nut away as we need the shaft afterwards.
    We still are perplexed as to what stops the nut coming off - there is no sign of a split pin - cotter - split washer whatever. It has been on there for 35 years in salt water.
    Plan A is 1. remove the quadrant from the shaft; 2. remove the nut; 3. Wedge /lever the shaft up some 6 inches to clear the top of the rudder; 4. Lift the rudder off the skeg pintle; check/repair whatever . Replace everything and commission. Touch wood.

    Thanks
     
  6. alan white
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    alan white Senior Member

    Can't you cut the nut away without damaging the shaft? A diagonal cut from the side weakens it (careful to limit depth of cut), and then drive a cold chisel upward into the cut or attempt turning it. Nuts are cheap, shafts are not.

    alan
     
  7. MMNet SEA
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    MMNet SEA Junior Member

    Thanks ,
    We may have to do some thing like that. Unfortunately the photos don't show
    how little space there is.
    Will report progress .
    Cheers
     
  8. MMNet SEA
    Joined: Feb 2007
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    MMNet SEA Junior Member

    Progress report,
    Got the nut off ! Hooray!
    Could not lift shaft out of rudder with wedges and pry/wrecking bar.
    Made up "screw lifter" - placed in the space below the bottom end of the shaft - (unscrewed the bolt until shaft was freed) No problems with shaft or rudder bush.
    In the above process lifted Quadrant enough to see that the Key that had moved the keyway in the quadrant (could not see that before) Removed quadrant rebushed and cut new keyway. Reassembled the whole system - now all in line.
    Thanks everyone for the input.
     

    Attached Files:

  9. alan white
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    alan white Senior Member

    Nice drawings, by the way.
    Glad to see it all done. Confused about what you meant by the key/keyway in the quadrant------ if the quadrant has a keyway, how can it move? I can only guess the quadrant has a press-fit hub, which got spun.

    A.
     
  10. MMNet SEA
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    MMNet SEA Junior Member

    Sorry my nomenclature rusty. What I meant to say that the rudder's key in the
    top of the shaft had turned with the shaft, enlarging the keyway in the quadrant. This meant that the quadrant was about 15 degrees out of it's original alignment. here's a rough sketch
     

    Attached Files:

  11. alan white
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    alan white Senior Member

    I guess the quadrant is some soft material. Thanks for the clarification. Better for the system to have the "weak link" accessible and easily removed.(and a tiller to fit on if necessary).

    A.
     
  12. Frosty

    Frosty Previous Member

    I dont want to say I told you so --but-----
     
  13. MMNet SEA
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    MMNet SEA Junior Member

    Frosty ,

    Unfortunately the keyway and key are not visible from the top of the quadrant - this quadrant is also clamped - all the nuts/bolts were painted, no
    cracks in the paint.
    Therefore, it was a wise precaution to check out the rest of the rudder, eliminating all other potential faults one by one.
    This rudder has been operational in salt water for over 35 years giving faithful service - 5 atlantic crossings - a circumnavigation - South Pacific to the North Pacific. A little TLC goes a long way.

    Now looking at adding a skid roll bar, 1" solid steel round bar ; one end welded to the forward end of the bottom of the skeg and the other end welded to the aft end of the bottom of the keel. What thought do you have on that ?
    --------------------------------------------------------
    Alan,

    Do have emergency tiller that fits over the squared top of the rudder shaft that protrudes above the quadrant - this is operated blind in the aft cabin at the aft end of the double bed once you have got all the bed linen - the mattress - the boards off. Never had to use it , but I suppose a single-hander could steer using a fluxgate or a GPS with an external antenna.
    From a positive point of view, better than standing out in the sleet and rain trying to read the binnacle compass.
     
  14. Frosty

    Frosty Previous Member

    A bar connecting from the rudder skeg to the keel is a must in these waters. Fishing nets and carelessly discarded ropes are common place. The bar will assist these objects in flowing freely out and under the boat without snagging.

    Not to mention strenghtening the rudder skeg for those days when you reverse into things.
     

  15. MMNet SEA
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    MMNet SEA Junior Member

    Not to mention strenghtening the rudder skeg for those days when you reverse into things.[/QUOTE]

    Are you trying to put a hex on ?
     
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