Re-epoxy hull?

Discussion in 'Wooden Boat Building and Restoration' started by samhaskins, Mar 21, 2014.

  1. samhaskins
    Joined: Mar 2014
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Guernsey

    samhaskins New Member

    Hello everyone!

    I have a lidguard 10m sloop. She is double diagonal Kauri wooden boat with an epoxy hull, and a fiberglass plywood deck

    She was neglected for a short while, and needs some TLC.

    Some of whats involved list:
    Re- fiberglass the plywood deck.
    Apply antifoul
    Paint topsides
    Repair (seemingly) small area of rot at transom/deck joint
    New Deck hardware & lines aft
    Replacing all thru hulls

    Now one thing I'm toying with is applying another coat of epoxy to the hull. Apparently the was a very small amount of weepage at the back end of the keel. I think that's the only real reason i'm even thinking about it (that and i'm thinking of applying a dark colour to the topsides, and her fairing is not the best!).

    My questions are:
    Should I be doing it at all?
    Should I not just leave it, 2 pack the topsides and then patch the keel, and other spots (removing a an old fairing block) etc?
    Do I take it right down to just past the epoxy primer?
    I'm assuming I apply just Epoxy (no cloth)?
    The (lead) keel looks like it would love an epoxy. So maybe just the keel, and the keel-hull joint?

    Any advice is more than welcome!

    [​IMG]

    Album Linkhttp://www.myalbum.co.uk/Album=FDMMLUVN
     
  2. pauloman
    Joined: Jun 2010
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    Location: New Hampshire

    pauloman Epoxy Vendor

    you would want to use a flexible epoxy paint (if you do use epoxy) and not the brittle marine epoxy intended for use with fiberglass cloth


    Paul Oman - MS. MBA
    A.K.A. “Professor E. Poxy” - “Old Goat” - “Epoxy Guru”
    www.epoxyfacts.com
    www.everything-epoxy.info
    www.epoxyguru.com

    epoxies since 1994
    Member: NACE (National Assoc. of Corrosion Engineers) -- SSPC (Soc. of Protective Coatings)
     
  3. PAR
    Joined: Nov 2003
    Posts: 19,133
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Welcome to the forum.

    I disagree in the use of epoxy paint, except as possibly the finish.

    There are several issues at play here and no single product is going to get them all. So, break the jobs down and address each as necessary.

    If you HAVE to re'glass the deck, do so, but don't make more work for yourself, if you don't have to. Most of the time, you just need to take care of bad spots, which means patches, instead of wholesale resheathing. If the deck is real bad, rip up the cloth or make patches to fair the bad area(s) level with surrounding surfaces, then use Xynole or Dynel instead of 'glass cloth. These are far more abrasion resistant and cost about the same as 'glass cloth.

    Applying antifoul is simple enough, assuming the prep is sufficient.

    If your current epoxy primer is in good shape, just touch up what needs to be fixed, saving some effort, money and preserving an other wise intact coating.

    Just applying epoxy alone really doesn't do much, but add a very thin plastic coating. Fabrics and fillers are what makes epoxy so effective as a coating, so if needing to "improve" something, you'll need some sort of fabric and/or fillers too.

    Since you're in the mood, drill out all the fastener holes in the hull, including the thru hulls. Back fill these oversize holes, with thickened epoxy and let it cure. When cured, drill out the fastener holes to the thread size and insert the fasteners with slightly thickened epoxy, which will bond the fasteners in their holes, but more importantly, because the holes are coated with epoxy, no moisture can get to the surrounding wood.

    Lead ballast casting are just fine with just antifouling on them. Epoxy isn't going to help it in anyway. If the casting to hull joint needs addressing, this is a different story, but if the joint is tight, just paint the ballast and call it a day.
     
  4. jehardiman
    Joined: Aug 2004
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    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Sounds like possible grounding damage. Is the front/forefoot of the keel dinged? If the keel was levered back into the hull there could be hull and/or floor damage. Anyway, if the keelbolts are weeping, the keel really should be dropped, bolts checked, and the faying surface re-caulked or new irish felt laid.
     
  5. samhaskins
    Joined: Mar 2014
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Guernsey

    samhaskins New Member

    Grounding

    Thank you all for the replies!

    With regards to grounding- yes that is my impression too. A surveyor looked at it before I bought it (for the previous owners) and told them not to worry about it. That said I am wanting more bluewater sailing, so will want piece of mind. It seems logical to me that if indeed there was any weepage (i didn't noice any) then you need to inspect the bolts to check they haven't corroded. So I will grind back, and investigate a bit more, probably biting the bullet and dropping the keel- which i really dont want to do!

    Parts of the deck had cork on which was removed rather brashly, leaving an uneven surface, which requires prep to make good and add some kind of non-slip paint/surface. I was also was planning on replacing the somewhat tire and beaten toe rail, leading lines aft, fixing new winches, travellers etc. All that said, I have reassessed whether I NEED to redo the whole deck- and you're right I don't think I need to do the whole thing. I will stick my new moisture meter on, get a second opinion and go from there. The problem here is that there are very very few wooden boat builders (none in fact), making it hard to find somebody with the knowledge I require!

    In relation to the thru-hulls- that's a nice way of doing it, thinking about it though, shouldn't you add one step? Where you do the same, but for a wooden block, which you can then screw into with the seacock, meaning you aren't damaging the hull each time you change, but the (sacrificial) block.
     

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

    PAR Yacht Designer/Builder

    I don't use wooden backing blocks any more, but prefer G-10 or metals. These have less issues, particularly G-10.

    The idea with bonding fasteners and all hull penetrations, is to form an epoxy ring around the wood, fasteners/item (thru hull for example) interface. In this way, even if the bedding fails and it leaks, the wood surrounding the fasteners or item penetrating the hull, will be sealed and protected from moisture. Most folks can live with a minor leak, knowing the surrounding wood is safe. You can deal with it at the next haul out and let the pump(s) keep up in the mean time. Lastly, you can tap (thread) G-10, which is a handy thing (assuming you have a 1.5" tap for a thru hull). I don't even use wood screws any more, just machine screws or bolts. They hold better (amazingly enough according to testing) then sheet metal or wood screws, if bonded into the substrate.
     
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