crack on keel lead cast on fiberglass santana 30

Discussion in 'Sailboats' started by marto, Jun 6, 2007.

  1. marto
    Joined: Jan 2007
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    Location: philadelphia

    marto Junior Member

    I found this keel cracks http://www.flickr.com/photos/40367953@N00/
    I found that the keel bolts were slightly loose.
    what would be the proper repair?
    also the anyone knows at how many pounds I tight the bolts.
    one of the bolts quips coming up as i tight it.
    I heard that grinding the fiber glass and laid new mat only will do it for the exterior part.
    i wanted to do some offshore sailing this summer but with this keel problem I hesitate at list until I'm sure it will keep attach to the hull in ruff weather.
     
  2. Tim B
    Joined: Jan 2003
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    Tim B Senior Member

    I suggest that you get a local boat-builder to have a look at it. You can't tell much from just the photo.

    Tim B.
     
  3. Kessica
    Joined: Oct 2006
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    Location: London UK

    Kessica Junior Member

    Im no professional boat builder or restorer, however when it comes to fibre glass repairs the key as always is preperation. Grinding out the cracks and following them through till the crack dissapears. Then its case of remoing all traces of dust, degreasing and then laying up with fibre glass mattingbuilding up layers as required and making sure there are no voids caused by trapped air and thet you also get a good penetration of resin through the matting.

    If a Gelcoat is required on the surface then in general a polyester based gel will work on most resins but its always best to try a small test piece first to be sure.

    After some sanding and working your way up to P1000 Wet and Dry you should end up with a good repair. The problem with many gels is the matching of the pigments, always difficult.

    When mixing 2 part resins and gels always follow the instructions regarding the amounts, failure to do will either make a weak mix, or a mix that get so hot, it will could do a lot of heat damage such as cracking on adjacent glass.

    If no-one can offer any advice on the torque of the bolts then looking at the size of the bolts and threads would give you a feel, but it would also depend on what the bolts went through. The last thing you want is to warp anything through over tightening. Personally I would tighten up after applying a very small dab of locktite and then watching closely as more foot pounds are applied; backing off if anything looked under a lot of strain.

    But the best advice is as Tim's post, seek out a professional :)
     
  4. marto
    Joined: Jan 2007
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    Location: philadelphia

    marto Junior Member

    thanks kessica,
    I repaired few deck core problems in the boat last year and it ended pretty good, so I'll laid mat this time.
    yours seems good advise, I will follow it.
    regardless the keel bolts, I have to figure it myself.
    I think 80 ponds will be about right.
    I been reading other forums about replacing keel bolts and people do it themselves ocasionaly, my budget is tight or no budget. just materials and my work, thats how I have put this old boat to sail again and thats how I'm planning to keep it going, some times there is no choice, but to go sailing anyway.
    how may layers seem right for you.
     
  5. Kessica
    Joined: Oct 2006
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    Location: London UK

    Kessica Junior Member

    It really depends on how deep the cracks go and the depth of the existing glass . You will discover that once you grind out the cracks. It would be best to bring up the layers to a little below the existing surface to allow for a gel or resin final coat ready to sand down to the original profile. You dont really want to spend a lot of time sanding down as it can be hard work and leaving having glass matting exposed at the surface is probably not a good idea.
     

  6. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I think you need to really have a good look at that laminate. Grind it back, little by little, checking where the cracks go and stop. If you've got fractures nearly so or clean through, you have issues. The damage looks like the result of a strike, there may be some buckling on the opposite side of the fin, which would confirm the strike damage. If this is the case, the bolts may have bent or possibly a few have sheered or cracked.

    When a set of bolts gets loose, the ballast rocks around underway, which puts tremendous loads on the laminate, bolts, nuts, etc. Things usually degrade quickly after that.

    I know you budget is tight, but if grinding reveals deep cracks or the bolts don't tighten down, accepting even torque across all, then you need to have a pro come by and look her over. This isn't something you should make "good enough" and hope for the best.

    Maybe you got lucky and those are minor stress cracks, from the ballast moving around a little, from loose bolts. You'll know as soon as you reveal the crack depths.
     
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