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The Double Paddle Dory
Design By Einsteen einsteen@yahoo.com

Using these plans, you can build a boat whether you have boat building experience or not. If you’re boat oriented and have read a bit about boat building, you probably won't need any supplemental help. If you're a casual boater with little experience, you may need to read up on the some of the building techniques I talk about. The libraries are a good source of boat building books, as are most well stocked bookstores. The book that you may find most helpful for this project is "Build the new Instant Boats" by Dynamite Payson, published by International Marine. There are quite a few others. (Editors note: Dynamite Payson sells his books directly to the public at 207-594-7587 or at his Website "instantboats.com". They may also be purchaced by credit card at my site, smallboats.com ) But don't put off a project like this if it's something you've always wanted to try. I’ve seen and talked to too many people who spend their lives waiting for some almost mythical event to take place, whether it's finding the right book, buying all the right tools, or getting finished with all the chores around the house. If truth be told, the chores will never be finished, you may never find the right book, and the tools you currently own will probably do the job quite nicely. So get off your duff, buy some boat building materials, and build a boat!

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The motivation for this design was my desire for a light, inexpensive, easy to build one person boat I could use mainly as a tender for my 1936 Baltzer cruiser. I wanted something I could keep on my cabin top and use while cruising alone, for the occasional forays ashore and the mandatory explorations of thin waters where the 2 1/2' draft prevents the Baltzer from treading. I wanted the boat to be

extremely light so I could lift it up onto my cabintop alone without having to resort to mechanical means. I have always striven to keep things as simple as possible, and an extra mechanical system to break down was not something I wanted to deal with unless absolutely necessary.

I also wanted something truly car-topable, for those times when local rivers and lakes beckoned. I have a 12' canoe that weighs in at about 55 pounds, and while that's relatively light. I find it a bit of a chore to lift up onto my car, especially in windy conditions, let alone portage any distance. Something around 30 pounds seemed about right to me. For that weight I wouldn't have to be too concerned with ultra-light construction materials or techniques. I could use 1/4" ply, which in a boat of this size adds the necessary heft to give me a feeling of security. Other hull options didn't work out quite so well.

A frame covered with heat shrink dacron or the like would have fit the bill in terms of weight, but I can't get used to the idea of a hull material I can see through, and the fear of holing it on the first sharp stick or rock that happens along leaves me very uneasy. Using 1/8" plywood in lapstrake fashion would work well also, but I didn't want the project taking any longer than necessary, and that is a very labor intensive technique.

The boat I designed fit my criteria to a tee. The finished weight was 28 pounds, the total time to build was about 16 hours, (not counting time to let varnish or resin dry), the total cost was around $75.00, and the finished boat is sturdy, works well, and very important to me, looks good. (Every time I've had her out I've gotten favorable reviews.)

She takes a pounding well, be it wave or rock, and can be powered by oars, (if a seat is added to give a bit more sitting height), or a double paddle. She's not quite as fast as a kayak, but a good bit more stable. The stability comes at the expense of speed, because to get the stability, I designed in a fairly typical dory "tombstone" transom. This gives extra bottom width aft, hence the stability, but since the rocker was kept small in order to give directional stability, (to prevent fishtailing while paddling with a double paddle), the boat drags a bit more transom than it should for optimum speed. It's hard to get any real speed in boat this short anyway. As with any boat design, compromise is the evil villian with whom we must do battle. There are no perfect solutions, hence no perfect boats. But this one does what I set out for it to do, so for that I raise my beer stein in a hearty salute.

This is the perfect project for a first time boat-builder. For very little cost you can get your feet wet, (figuratively speaking), and have a handsome, usable, and fun boat for your trouble. This is a good introduction to taped seam construction, and the skills you hone here can be applied to larger craft in the future. I'm currently finishing up a 12' dory style skiff for use with a 10 horsepower or so outboard. It's also an inexpensive foray into the boat building arts, and should prove to be alot of fun. I'll make plans available if it works out as well as I think it will.

Lofting

As with any boat, the first step is lofting. I use the term very loosely, for the panel outlines are drawn directly on the plywood and can't be easier to lay down. (see sheet 1) I used a 10' sheet of exterior luan plywood and thus saved myself the trouble of scarfing a piece of plywood onto the end of a standard 8' sheet. The 10 foot sheet of plywood can be ordered at most lumberyards and will be a bit more expensive than buying two standard size sheets, but the boat is so inexpensive, I felt it was worth the cost in saved labor time. Sheet 4 shows a detail of a standard 10:1 scarf, if you want to go that route. What scarfing entails is planing and sanding the last 2 1/2" of each sheet of plywood to be joined, so that the edge view looks like an elongated wedge. The two wedges are then epoxy glued together to form a longer piece. If you're scarfing a piece onto a standard 8' sheet, remember to make the extra piece 2' 2 1/2", not just the 2' you might think you need to bring the length up to 10', because you lose the 2 1/2 extra inches when you glue the two sheets together. If you need a bit more guidance for the scarfing, most boat building books will give very clear instructions with pictures. The procedure isn't as complicated as it might sound.

The toughest part of the lofting is getting a fair line for the curved hull side. After you draw in the stem and stern lines for the first hull side, you spring a batten between points A, B, and C as shown on sheet 1. A batten is just a thin strip of wood held against two nails at points A and C and "sprung" downward at point B, (the midpoint), untill the 13" mark is hit. Pencil in the line and you should have a fair curve. What I used for the batten was a 1/2" strip I ripped off the 12' 2" x 4" specified in the materials list. I later used this strip as one of the gunwale strips. Buy the clearest, straightest grained 2" by 4" you can find. Knots bigger than about 1/2" aren't acceptable.

Building

After you draw the panel outline for the first hull side, cut it out with a saber saw and fair up the edges with a sander. This boat can certainly be built without the use of power tools, but figure on at least double the 16 hour construction time I talk about.) You can then use this hull side as a pattern for the other hull side.

The next step is marking, cutting out, and sanding the transom.

Now you want to construct the hull form, and because this is a throw away after the boat is completed, use whatever you have laying around. I used for the original boat an old 1" x 2" furring strip and it was more than adaquate. Glue and screw the form together as per sheet 2.

Now tack the hull sides to the form at the midpoint of each hull side. You can use a pair of saw horses or whatever might be convenient to hold the boat up at a convenient working height. Tie the bow together with a few pieces of wire passed through pre-drilled holes, then tack on the transom. The wire and the tacks, (1" brads), will be left in place until after the wood flour/resin mixture and fiberglass tape are cured, then removed. You can leave a bit of each brad sticking out so you have something to pull out. As for the wire, just snip it off on the outside of the hull and pull it through. After you’ve got everything to hold together, turn the boat over so you can work on the inside joints.

You're now ready to fill the two transom joints and the bow with a mixture of resin and wood flour. I like to use wood flour because of its appearance. It's a pleasant match to the wood when left bright.

("Bright" means stained and varnished or just varnished, as opposed to painted.)

First mix up some resin and hardener. Start with about 8 oz., and paint the three joints with the resin. Now mix in some wood flour until it's the consistency of peanut butter. Spread this mixture into the joints with a plastic applicator which is normally sold for auto body filler work. Cut a radius into the applicator. You want to form a rounded fillet a couple of inches across, and maybe " thick in the center. See sheet 3. While the wood flour mixture is still wet, bed some strips of fiberglass tape into the fillets, then mix up and apply some new resin to wet out the tape. Be careful to press out any air bubbles that might occur during the wetting out.

After this has cured, turn the hull over and lay on the remainder of the plywood. Tack it down and check the hull for fairness. (The curves should look true and "right" to the eye. From underneath, pencil in the outside line of the hull sides onto the plywood, then use a saber saw to cut out the hull bottom. Tack the bottom back on and carefully turn the hull over. Now finish the two fore and aft seams with resin, the wood flour mixture, and tape. Allow to cure.

Next, carefully sand the hull bottom where it sticks out from the sides, and round the edges of the bottom so the fiberglass tape will lay properly. Tape the outside seams. You’ll only need to use a wood flour mixture where there are gaps, or to fill holes in the hull where you tacked during earlier procedures. To tape, first coat the wood with resin in the area the tape will go, lay on the tape, then wet out the tape with more resin as you did earlier over the fillets of wood flour. Let it all cure.

Now, rip two " strips from the 2" x 4'. These, along with the strip you earlier used as a batten, will form the gunwales-the strips of wood running along the top of the dory on the outside of the hull. These serve to stiffen the structure of the boat. Attach the gunwales to the outside of the hull and fasten them from the inside of the hull with 5/8" brass or bronze wood screws. Round headed screws are a nice touch. The screws should be spaced around 8" or so. Attach the first gunwale strip whole, then trim the ends. Attach the second strip and do the same. Thetransom strip should go last.

The attaching of the gunwale strips, the fitting of the thwart, and the last step in the actual construction, the fitting of the skeg, are the only areas of the project requiring any real joinery work. Since this is the case, try to take some care here, but remember, on a project like this, microscopic tolerances aren't necessay or called for. However, fits that are too sloppy will detract from the appearance of the boat, and more importantly, since the boat gets much of its stiffness from the gunwales and the thwart, a sloppy fit could also detract from its seaworthiness and longevity.

The point is, don't let a lack of woodworking ability or experience stop you, but use some care. And let's face it, if the worst thing that happens is that you have to spend another $4.00 on a 2" x 4' because you screwed the first one up, we’re not talking major loss.

A problem I think most people have who would like to try a project like this but don't, is that after looking at projects done by amateurs and professionals in the glossy boat publications, they're scared off, because they don't think they can recreate the perfection seen in the magazines. To that I say, well maybe not, but you can turn out a reliable and functional boat anyway. And there is something very rewarding about doing it yourself. As for appearance, if you use some care I think you'll surprise yourself.

Now rip a 1" strip off the 2" x 4" for the thwart. It's installed midship through the gunwales with a couple of 1 1/2" wood screws. See sheet 1. The thwart appears midship as a short line connecting the two hull sides. Countersink them and fill the holes with a wood flour mixture. The thwart should be around 34" long and beveled on the ends to fit the contour of the hull sides.

Use the remainder of the 2" x 4" for the skeg. The skeg is strip of wood extending downward from the bottom of the hull, starting around 2" from the stem, running backward down the middle of the hull bottom, and ending around 2" from the transom. The skeg helps to give the boat directional stability and adds stiffness. Cut the piece of wood to length, then plane the sides so they angle up from what will be the base. The base will be around 3/4" wide 1 the top portion of the skeg around ". (See the cross section of the skeg on sheet 4.) You'll also have to plane a bit of height from the skeg, leaving the finished skeg somewhere in the neighborhood of an inch high. Attach this from the inside of the hull with 1" woodscrews bedded in a bit of calking.

Step back now and admire your handiwork. You're now standing in front of a boat! To finish things up, you'll want to sand both the interior and exterior of the boat and seal it all with a coat of resin. Sand again, then give the boat a couple of coats, (sanding between), of U.V. inhibiting polyurathane. To get a mirror finish will require a bit more work at this point, but the boat will look good as is.

There you have it. A handsome, useable boat with under twenty hours and about $80.00 invested. Use her with care and with pride.

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Materials List

1. 1 sheet 4' x 10' exterior luan plywood $32.00

2. 1-12'x 2" x 4" (douglas fir it available) $5.00

3. 1 gallon polyester resin $16.00

4. 16 yards 4" fiberglass tape $11.00

5. 30 5/8" brass woodscrews & 4 1 1/2" brass woodscrews & 10 1" brass woodscrews $6.00

6. 1 quart U.V. inhibiting exterior polyurathane $10.00

7. Sandpaper

8. 1" brads

9. a few feet of uninsulated wire

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Plans

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If you have any questions, e-mail me, einsteen@yahoo.com

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