Repairing a small section of my boat sole

Discussion in 'Materials' started by belsitj, Aug 13, 2011.

  1. belsitj
    Joined: Jul 2011
    Posts: 15
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: North Olmsted, ohio

    belsitj Junior Member

    Hello
    There is a small wood section of the sole on my 94 Aluminum Lund that is really rotten. I am only planning on keeping the boat for another 5 years so instead of going through the pain of removing the consoles and replacing the whole floor I am thinking about just cutting out a section, maybe 2' x 2' and replacing a piece of the sole. Of course when I do that if I find more damage I will probably have to replace the whole sole.

    My question: Someone told me if I used regular plywood to replace that section I should first dilute resin with acetone and brush it on so the resin soaks into the plywood. Then coat it again with a thick layer of resin(undiluted). Does that sound right and do you think that would be good enough to last 5+ years?

    Joe
     
  2. tunnels

    tunnels Previous Member

    Diluting resin just soaks to the first glue line so wont penetrate a much as you think !!
    Use ply with less plys!! that are thicker plys!!! and yes thin the resin (what resin are you refering to ????) but dont over do it !!
    Edges and top and bottom surfaces will soak at differant rates so keep applying to it till it wont take any more !Specially the edges !!!:p
     
  3. belsitj
    Joined: Jul 2011
    Posts: 15
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: North Olmsted, ohio

    belsitj Junior Member

    Thanks Tunnel.

    Not sure what type of resin, new at this and need to do research. Someone said epoxy resin in a few of the threads. Not sure if that is what I would use or not. Do you have any suggestions on the proper mixture for diluting the resin? Once it does not absorb anymore I assume I coat it with undiluted resin?

    Thanks for your advice and the knowledge of your experience.

    Joe
     
  4. Stumble
    Joined: Oct 2008
    Posts: 1,913
    Likes: 73, Points: 48, Legacy Rep: 739
    Location: New Orleans

    Stumble Senior Member

    Bel,

    Never, ever thin down Epoxy. It destroys the mechanical properties of it, and acomplishes nothing. A surface bond of epoxy to wood is stronger than the wood itself, so deep penetration acomplishes nothing. And there is little credible evidence to believe that thinned epoxy penetrates significantly deeper than unthinned. In addition the solvents used to thin epoxy create either pockets inside the mass of volatile compounds that can become caustic, or as they evaporate create micro-fissures in the mass that allows water to intrude.

    Typically the recomendation is 3 coats of neat (unthickened) epoxy on all exposed wood (including the old sole you cut into). I usually start with a slightly thickened base on the edges of the plywood to fill any gaps, say about ketchup consistency, wait for it to cure, then three coats of neat epoxy. All of this can be done off site, it is just material prep. Then install the encapsulated board. Remembering to fill any fastener holes as you go with neat epoxy as well.





    For completeness only... There some very small and far between exceptions to this, but unless you are a chemist, or professional boat builder they don't apply.
     
  5. BATAAN
    Joined: Apr 2010
    Posts: 1,614
    Likes: 101, Points: 0, Legacy Rep: 1151
    Location: USA

    BATAAN Senior Member

    Stumble has it right and his technique will give satisfactory results. You can cut out your 2x2 section of sole and replace it, but be sure to support the edges. Usually some strips of ply epoxied and fastened under the edges of the hole give firm support. Treat strips same as the patch, 3 coats epoxy to seal before installation, then fasten in place with thickened epoxy and screws.
     
  6. belsitj
    Joined: Jul 2011
    Posts: 15
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: North Olmsted, ohio

    belsitj Junior Member

    Thanks Stumble and Bataan. Will be starting tomorrow and I will let you know how it comes out when I am done. Wish me luck!!!!
     
  7. BATAAN
    Joined: Apr 2010
    Posts: 1,614
    Likes: 101, Points: 0, Legacy Rep: 1151
    Location: USA

    BATAAN Senior Member

    Don't fit too tight before coating, as it builds up.
     
  8. Stumble
    Joined: Oct 2008
    Posts: 1,913
    Likes: 73, Points: 48, Legacy Rep: 739
    Location: New Orleans

    Stumble Senior Member

    Bataan here makes a good point, you should install a flange under the existing sole to rest the patch on. Follow the same encapsulation process as for the patch, but use 4" strips of plywood around the edge. Recessing the strips half way.

    This way you have a physical support to hold the patch in place. Then once the initial epoxy is cured, come back and add a filler coat of thickened epoxy to the edges where the patch is to make it flush with the existing sole.
     
  9. belsitj
    Joined: Jul 2011
    Posts: 15
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: North Olmsted, ohio

    belsitj Junior Member

    great suggestions, thanks
     
  10. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Since your patch is on top of the existing sole, bevel the edges to make toe stubbing a non-issue, but more importantly to ease point loading around the perimeter. Also consider what will happen to water that has boarded. It'll need channels to drain aft and a slightly curved front edge will also help too. The channels can be simply not permitting the patch, to run out directly against the hull shell, seating, etc., but leave a 2" or so path way, so the water can drain aft and not dam up against the patch.
     
  11. belsitj
    Joined: Jul 2011
    Posts: 15
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: North Olmsted, ohio

    belsitj Junior Member

    Thanks PAR. I am going to cut out the rotten part of the old sole and put in a new piece (epoxied as the guys above suggested). Most of the bad parts are right below the two front seats. I am thinking about putting like a small platform over the replaced sections and if I do that will keep these tips in mind. Going to start today so I will have a better idea what I am doing once I see how much damage there actually is.

    Thanks
    Joe
     
  12. belsitj
    Joined: Jul 2011
    Posts: 15
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: North Olmsted, ohio

    belsitj Junior Member

    Well, spent most of the day doing it but have half the floor out now. The other half should go a lot faster now that I know how the floor is tied and I know what the heck I am doing. Next is the dry fitting of the new floor and the resin.

    Two questions:

    Is there a particular type of resin I should ask for?

    Do I coat the top and bottom of the floor with the resin or just the bottom and sides. I am going to put vinyl on it and not sure if the vinyl will stick to the resin?

    Thanks
    Joe
     
  13. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Any wood going into this boat needs three full coats of straight epoxy applied to it. This includes screw holes and cutouts. You can kill two birds with one stone by using one or more of these coats as part of the bonding process or tabbing. For example if you have only a single coat on the wood, but you'll apply two or three layers of tabbing fabric, then under this fabric will receive the necessary "film thickness" needed for true waterproofing. This is the bottom line, film thickness. You need enough to insure it's waterproof, which three coats will provide.

    You'll save some money buying on line. Bateau.com and other reformulaters offer small quantities of epoxy for about $60 a gallon, retail. Unless you buy bulk (why) you're stuck with this price, but the major brands are in the $100 a gallon range so be grateful.

    Vinyl will stick to the epoxy, just tooth it up with some 100 grit before you apply it.
     
  14. belsitj
    Joined: Jul 2011
    Posts: 15
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: North Olmsted, ohio

    belsitj Junior Member

    Thanks PAR but I am a little confused. So you are saying I should put one coat of straight epoxy, let it dry, then put a 2nd and 3rd coat and while it is wet put the vinyl over it. I am sorry, just confused.
     

  15. BATAAN
    Joined: Apr 2010
    Posts: 1,614
    Likes: 101, Points: 0, Legacy Rep: 1151
    Location: USA

    BATAAN Senior Member

    Coat the item and where it goes, 3 coats is best but 2 will do. Let it dry. Install it. Possibly install it with thickened glue and screws. Let it dry again. Treat it like any floor after that.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.