A few questions from a newbie

Discussion in 'Wooden Boat Building and Restoration' started by clamdigger, May 28, 2009.

  1. clamdigger
    Joined: May 2009
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    Location: Barnegat bay

    clamdigger Junior Member

    I am restoring a 19' all cedar, barnegat bay garvey. I am replacing the planked transom with 2 pieces of 3/4 plywood screwed and epoxied together. I also need to replace the gunwales and some of the battons holding the side planks together, as well as replace any of the bad fasteners holding the good battons and bottom planks on the boat. was debating whether i should use nails or screws for this. In the days of when this boat was built everything was nailed. when it comes to the battons they used a 2 man operation and a nail that was 1/2" longer than the thickness of the sides and battons, with one man using a nail set from the outside and the other man peening over the excess length with a mawl on the inside creating a crude "locknail". I believe this was because it was all they had at the time. As far as material goes, is there a benefit of silicon bronze over stainless? Cost is a minor issue.

    I have been looking around at center console deigns and am debating on what design to build, I have a basic design in my head and would like to add a seat foward of the console with a storage area/possible livewell beneath it but would like to add some type of electronics box where i can put my gps/depth finder and see it while running. Does anybody have any pics of consoles they have built with or without measurements?

    I will be using plywood for decking in the boat, but unsure of what thickness to use. Was thinking 3/8" or 1/2" but open to suggestions. The floor will be well supported. Would epoxy coating the plywood be enough or should i lay some mat down as well. i would also like to put some type of non skid in the paint. any suggestions on that?

    Thanks in advance
     
  2. clamdigger
    Joined: May 2009
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    Location: Barnegat bay

    clamdigger Junior Member

    Maybe Restoring is not the right word for describing what im doing to this boat. Putting some life back into the old girl and updating her a bit is more accurate. She was a work boat powered by a 50 horse outboard with a lever/cable steering setup in the stern behind a single bench and the rest of the cockpit was wide open and used for clamming and net fishing over the years. its got some family history tied to it so i dont mind putting the work into it. she had a spongy deck and a rotten transom when i got it, most which has been gutted and currently is being stripped down to bare wood which is some of the prettiest looking cedar i have ever seen..or smelled. I'll try to post some pics when i get a chance.
     
  3. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    You described clench-nailed construction. Actually a good way to hold a boat together. The nails were probably galvanized and if you replaced them you might just use the same thing to avoid mixing metals. Some stainless here and there would be okay however.
    If the deck isn't a walk-on surface, and there's some crown, and enough framing, go with 1/4" plywood, maybe AC grade fir (unless you can find some decent marine ply locally) with a layer of light glass cloth over it set in epoxy.
    Otherwise, 3/8" isn't too much more weight, and it can stand being treated roughly better than 1/4".
    Sounds like you're on the right track. I think PAR will probably sniff out this thread. He'd be a good source of advice regarding most aspects of that boat, especially the transom.
    Sounds like the planking is carvel, but flat. Those battems as you call them... do you mean frames? Is the framing set up dory style?
     
  4. clamdigger
    Joined: May 2009
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    Location: Barnegat bay

    clamdigger Junior Member

    Thanks alan, by deck i meant the floor in the boat, sorry for the confusion. I'm up for any advice that i can get as this is my first major project, most of my work being in the engine room of much larger sportfish boats and yachts. I have done my share of stringer repair and glass work, nothing as large scale as laying a whole hull with mat though. I know a few guys who do fiberglass work for a living and they will help me through that stage. Im not sure on the carvel planking, the sides of the boat consist of 3 cedar planks that run from bow to stern, appox 1"x10", which are held together by 1"x3" boards that i was told by my grandfather who built a few of these boats, are called battens, or battons perhaps? I guess they could be called frames. I've never paid much attention to a dory's construction but this boat has 2 solid oak stringers approx 4"x6" in the center of the hull about 2' apart, and down each side of the boat is a 2"x3" board that follows the curve of the sides. The battons are sandwiched between this board and the inside of the side planks. The bottom is planked with 6"x1" planks and get smaller toward the bow.

    After grinding and peeling and picking many years of glass patch up jobs, i discovered that the transom was a pile of black mush under the glass, and the only thing holding it to the boat were 2 metal angle brackets attached from the stringer to a newer piece of plywood through bolted to the motor plate for the outboard. Along with the transom, the first 3-4" of the side planks are a little black and soft.

    My plan is to support the inside with temporary bracing so the boat doesn't go floppy when i cut/shovel out the old transom, then making sure it is "square",(not in shape, as nothing is square on a boat lol) Follow the old line and remove 4" to put me back on good wood. Then create a template out of some scrap 3/8 ply before i go cutting the expensive wood. I will then cut my 2 pieces of 3/4 ply with a slight overcut to allow for fine tuning, epoxy and screw them together. After some sanding to get a tight fit i will screw it in through the sides and bottom. Not sure if i should filet the corners with epoxy or run a 2"x3" block in the corners to get me away from the edge of the side planks.

    Sorry for the long post, any and all advice is appreciated.
    Matt
     
  5. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    The clenches were probably copper, which is the traditional material. Galvanized is generally too stiff to bend well.

    The method your boat is built with is called batten seam and was a common technique, before plywood became popular. Batten seam construction has longitudinal battens, that back up each plank seam and often conventional frames as well. On small craft (like yours), most, if not all of the frames can be eliminated (the designer's choice) and athwartship stiffness carried by furniture and bulkheads.

    On a 19' boat, you'll want 1/4" or 3/8" decking, not 1/2". Generally a heavy duty boat will have decking the same thickness as the planking. A light duty version about 30% less.

    Powerboats have these 2 bilge stringers. They disperse bottom loading to the remaining hull shell. They are usually at least 3/4's the length of the boat, kind of dieing out near the bow. They are the strength of the boat.

    Use a 2x4 or two to brace the transom opening, so that when you spoon out the transom goo, it'll stay where it belongs.

    Figure out what type of fasteners you have. They'll most likely be bronze (except for the copper clenches). If they're bronze you have to keep using bronze (or copper). I suspect you've had some dissimilar metal issues, which has wasted away the fasteners. The metal brackets at the transom are steel I'll bet, which would be the culprit (or one of them). This is a common problem, people just don't know and it causes untold difficulties. You can't mix different metals. What happens it you create a battery and the fasteners literally dissolve. You'll find out when it's time to pull a few and they crumble.

    I wouldn't fillet the transom corners into the boat, use a nailer along the edge, with the transom bedded in polysulfide. This type of construction doesn't get along with plastic coatings very well, just way too much movement for it to be effective in repair situations.

    Post some pictures Matt, so we know what we're dealing with.
     
  6. clamdigger
    Joined: May 2009
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    Location: Barnegat bay

    clamdigger Junior Member

    Thanks PAR for pointing me in the right direction. I'll try and post some pictures later today.
     
  7. clamdigger
    Joined: May 2009
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    Location: Barnegat bay

    clamdigger Junior Member

    Also, what kind of wood would be good for replacing some of the rotted battons? The originals were cedar, but cedar is hard to come by around here unless you have it milled. i was told douglas fir might be an option, any thought on this?
     

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

    PAR Yacht Designer/Builder

    Douglas fir will be 50% heavier then cedar. You could reduce the dimensions of the battens, but this could be problematic.

    Some of the spruces in your are will be fine, I'd recommend white or black spruce. White spruce should be fairly common.

    Try to find a species that is similar in weight to the stuff you pull out.
     
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