keel wobbles

Discussion in 'Sailboats' started by alex folen, Jan 8, 2009.

  1. alex folen
    Joined: Jan 2009
    Posts: 43
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    Location: Green Cove Springs, Florida

    alex folen Flynpig

    Hello, my keel wobbles. It took some time to notice because we had to stare at it thru the trunk as the boat bounced against dock (...a minimum bounce with nice expensive bumpers placed just rite). The bulkhead members in the trunk area are not visably broken/ cracked. The keel does not SWAY slowly left and right, yet it is a wobble, a frequency 2 per second I’d say. When it wobbles it appears the whole underside emanating out from trunk flexes but dissipates about 1.5 feet from center trunk, as if the design allowed for it. If i were to estimate the distance of sideward travel at the bottom tip of the keel based on the wobble, +/- 2 inches? The boat, a Coronado 1969 - 30, has the fin keel, 5'6 draft, 8500# and keel weighs 2700# and i luv her.

    Was told several things by non experts.... Is a flex in the fiberglass near keel common? Oh, and the wobble? And if not, thought about applying copious glass to the flexing area. Some said the keel should not move at all. Gona pull her out and add to the list if need be.
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    The keel shouldn't move at all. You could have broken or loose bolts, possibly more serious issues. Have it inspected by a surveyor, while it's on the hard.
  3. alex folen
    Joined: Jan 2009
    Posts: 43
    Likes: 2, Points: 0, Legacy Rep: 25
    Location: Green Cove Springs, Florida

    alex folen Flynpig

    Thanks for the response, my thoughts exactly. However, I do know all the bolts are snug and there is no delamination in the trunk area. The keel seems to be firmly attached. The wobble is coming from the fiberglass which makes up the keel trunk area. It is hard to notice also as described. Just want to know if anybody has seen similar issues, and if it may be a design flaw as it is hull # 6.

  4. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    Much damage in the form of stress cracks could spell disaster down the road. I bought a Carter 33 a few years ago that had a design flaw that had already been repaired---- the keel root (deep fin keel) wasn't beefy enough, and the floors were made of foam which deteriorated when it got wet.
    The flexing caused leakage and the repair was to build up the fillet around the hull/keel area with a lot of fiberglass and resin, with mechanical fasteners holding the glass on as well. The floors had to be replaced too, with mahogany, I believe, bedded and glassed with epoxy rather than polyester.
    A lot of glass was laminated and when the job was done the boat sailed a few thousand miles offshore with no problems.
    Your best bet is to find a forum for your boat if possible to see what others have experienced. Otherwise, look at the problem as soon as you can, and as PAR mentioned, get a good survey of the problem.
    If your floors have let go, cracked, rotted, etc., that damage will even be obvious to a novice. Get into the bilge and see if you can find cracks. Drill holes in floors and see if the material inside is water-logged.
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