Seams corked only below the waterline, but not above.

Discussion in 'Wooden Boat Building and Restoration' started by Sather, Jun 13, 2015.

  1. sdowney717
    Joined: Nov 2010
    Posts: 852
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    Location: Newport News VA

    sdowney717 Senior Member

    I did not take out the cotton except in a few places to show the seams.
    The planks are 7/8 inch to 1 inch thick, the tiny cotton thread is packed between the planks far back, the white linseed oil putty is on top. Egg Harbor put very little cotton threads in the hull planks.
    I replaced cracked and broken dried out putty with a hard rubber. If it affected the hull in some negative way, I certainly dont notice that in the way it goes through the water. In this boat, one wood edge is square, the plank on top of seam, the other on bottom of seam has a slight bevel cut which is about 1/4 deep. Then the plank edge is square further back. If you examine a dried piece of Dynaflex, it is quite stiff and hard. It takes a good month to fully cure to that state. It is very loose coming out of the tube, it shrinks as it cures and harden up a lot. There were some places I had used that Dynaflex in between the planks from the prior haulout 5 years before, I found it very difficult to remove. I either used a thin blade kerf in the saw or used a utility knife to cut the seam. Dynaflex is elastomeric a little I suppose, but not very. The old linseed oil white putty certainly was doing nothing to prevent planks from sliding past each other which is why every seam was cracked like it shows in the picture.

    This hull before I did that had quite a few areas showing sunlight between the planks, especially up in the bow area which is the driest area of the hull planks. Now all that is gone, sealed up with caulk and paint. And it looks very nice seeing the plank definition.

    Here are another couple views
  2. whitepointer23

    whitepointer23 Previous Member

    Nice finish. I like the look of exposed seams. Mine are invisible except when one side dries in the summer.
  3. peterjoki
    Joined: Sep 2008
    Posts: 57
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    Location: Turku, Finland

    peterjoki Junior Member

    Thanks for the pictures. What a nice boat.

    Carvel plank construction is very different on both sides of the Atlantic.

    Here in Finland a "good" carvel planking fit is so tight that no light gets through. I understand that in the US a bevel and gap is left intentionally for caulking.

    This is why I don't build carvel. Do not have the practice to fit these planks in a cost efficient time frame.

    Gonzo does have a valid point but I wouldn't dismiss this fix yet. If the fastenings and frames are tight enough you probably wont notice any problems. The elongation properties of the elastomer you used will also be decisive.
  4. sdowney717
    Joined: Nov 2010
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    Location: Newport News VA

    sdowney717 Senior Member

    Truly, nothing unusual has happened and I wonder what would happen if it did happen? Boat has been in use since last October 2014. We just made last week a very rough bay crossing with the bow getting buried and then the stern getting buried in waves, and came back with out any hull troubles. Got really slammed around very hard. I now have to repair the oven door, it came crashing down and the hinge got bent. Anyhow, that was very unusual boating weather for us to be out in.

    On this boat, when new, the planks are tightly fitted and the caulking bevel used to stuff in very thin strands of cotton like kite string multiple straight strands. AFAIK, as the planks age and rub and swell and shrink the edges can be compressed and wear away. Planks will also dry and show light and swell up and not show light above the waterline. Evan a new plank will shrink.

    Also I have had this boat since 1998 and have done extensive hull repairs. I replaced transom 6 months after I got it. And other repairs 5 years later, look at this from earlier days.
    Just a few broken frames, LOL. Why they built so poorly? I made many hull structural improvements such as sawn frames behind the bent frames.

    I had every bottom hull plank off the boat at one time or another. And also the aft sides. Did repairs in quarter hull sections.

  5. waikikin
    Joined: Jan 2006
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    Location: Australia

    waikikin Senior Member

    Lots of people like the look.... some glass boats have seams molded in.

    Here is a timber boat, splined, wrapped in DB & epoxy ....... then seams detailed into the fill coat......

    We laid 3mm masking tape over the glass above splines, then skimmed 2.5mm epoxy fill over & stripped the tape while still green, after a little fairing ran some folded paper along the "seams" & there you have it.. fake detailed seams on a timber boat.....

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