Repairing wet strip planks.

Discussion in 'Wooden Boat Building and Restoration' started by simon, Sep 24, 2009.

  1. simon
    Joined: May 2002
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    simon Senior Member

    Hi,

    my boat is WRC strip planked. Around some of the skinfittings there seems to be some water entering the wooden core due to unproperly bedded fittings. The moisture meter shows elevated content in direction of the strips, measured on the inside of the hull.
    We are going to peel off the outer fiberglass layer around the fitting in the way of the strips to get an idea of the condition the wood is in. If the wood is in good condition, I was planing of letting it dry out and then put the glass back into place with epoxy. The wood around the skinfitting will be sealed with epoxy, so that if will not happen again.

    I would be gratefull for some feedback about the proceeding. Is there any adherence problem if the wood was soaked with salt?

    Thanks

    Simon
     
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Your plans seems good, get the glass peeled back and dry out the lumber. I like to bond hull penetrations, so this doesn't happen again. Bonding doesn't mean glue things on. What it means is you mold an epoxy "ring" at the penetration point, so if there is a leak, it's just a leak, not soaking into the wood.

    In a nut shell what you do is drill an over size hole, wet out and fill with thickened epoxy, let dry. Then drill for the correct size hole, but within the confines of the epoxy. Now a leak will just be a leak and the wood is protected by the epoxy.

    Scuff up the surface and wet out the wood, before putting on the 'glass patch, the epoxy will work fine.
     
  3. simon
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    simon Senior Member

    what about the tactics west system is suggesting, drilling 5mm holes every 25mm through the outer laminate into the core, drying out the area and then filling the holes with epoxy?


    Simon
     
  4. TeddyDiver
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    TeddyDiver Gollywobbler

    You can try that first and take new moisture readings after a while.. This proces could be boosted vacuum pumping on the other side and having vent holes on the other..
     
  5. rwatson
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    rwatson Senior Member

    If you apply vacuum over the holes - it will remove a lot of the moisture.

    A vacuum is the equivalent of freeze drying
     
  6. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Simon, West's technique is more to repair compromised cores. This core is just wet, so far as we know. Using duct tape, plastic sheeting and a dehumidifier can expedite the drying out process too.
     
  7. Herman
    Joined: Oct 2004
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    Herman Senior Member

    Western Red Cedar is a very durable wood species (40 years in ground contact durability) so I would not worry too much about the planks. Now just get them to dry using the above suggestions.

    The ingresspoint can be rinsed with fresh water to get rid of the salt. When dry the epoxy should bond without problems.

    If all else fails, there are types of epoxy that adhere very well to wet wood.
     
  8. simon
    Joined: May 2002
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    simon Senior Member

    Thanks for the advices.

    We have stripped the glass where there were elevated moisture readings. After 3 weeks, the readings were low enough to allow putting the fiberglass back on again. The cedar was still good enough, so that it could be left in place.
     

  9. Herman
    Joined: Oct 2004
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    Location: The Netherlands

    Herman Senior Member

    Good to hear all worked out well.
     
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