Hardtop Dodger
Shade and shelter are now required features on all my boats, and the mini-trawler was designed with a hard dodger to extend the cabin space. In the original build plan each of the cabin side panels was cut from a sheet of plywood, which would keep things simple, reduce the number of parts, and eliminate several epoxy/cleat steps. The practical problem that I needed to address once I started was how to build inside the shop, and then get the boat out -- the garage door opening provided only seven feet of vertical clearance. The build plan changed almost immediately and the dodger became an add-on.
In retrospect, that was a good decision. Keeping the boat on the trailer, rather than building on a floor frame, made it very convenient to dolly the boat around as the work progressed. And I preferred to keep the boat inside the shop for protection from the weather until I could get the transom finished and all the new plywood painted and protected. I briefly considered several variations of removable tops, and then started researching and sketching versions of “pop tops,” common on some of the smaller sailboats (like the one on our old Hunter 25.5).
I ended up with an unusual variation on a pop-top: mine has only one set of folding supports, and there is a second set of fixed supports that double as the dodger sides. The advantage of a pop-top design, in addition to being able to get the boat in and out of a normal garage door, is that the windage with the boat on the trailer would be significantly reduced. And if the wind out on anchor turns up, it might be nice to be able to literally “batten down the dodger.” Furthermore, dropping the top would also make tarping the boat over the winter months (or during any extended storage) much simpler and easier.
My pop-up dodger was designed in "3-D", not on a computer or on paper, as shown in the photo below. It uses two oak struts to support the front of the hardtop, and two vertical panels from ¼-inch plywood to support the back once the top is up. The hardtop would be supported by the wedge-shaped crosspieces, which would be secured to the rear vertical stiffener panels once the top is up. When the stiffeners are removed, for transport mode, the top scissors back and is supported by the top edges of cabin/cockpit sides. In the photo I was still figuring out how things would fit: the top wedge-shaped part in is actually on backwards, front to rear, in this photo. And the horizontal batten attached to the wedge represents the length of the dodger top.
Here’s another view once the design was a bit more developed. The top and the wedge are both still on backwards (sometimes the right design takes a while to come together...) but I was getting close to getting the basic design locked down (the panel attached to the cabin side is a mock-up for a cabin window).
The hard dodger top itself was a repurposed panel from an earlier project boat (the electric catamaran that didn’t make it in prime time and was dismantled). The front supports are bolted to the top and to cabin sides. The wide aft panels are removable. The grey rear supports are hinged at the aft crosspiece on the top, and they can swing up when the top is stowed. With the top up, the bottom ends are attached to the cabin sides, and they can fully support the top without the wide panels. But the wide panels add a lot more stiffness and strength to the structure, and give some protection from wind and spray. They give a great feeling of security when standing in the cockpit because you are surrounded by structure on three sides.
The repurposed dodger top was big enough to cover the cockpit, and it was nicely cambered to stiffen it and to shed water. As an experiment to save epoxy (and exposure to epoxy for large-area coating jobs), I had tried painting the 1/4-inch marine plywood panel, top and bottom, with a couple of coats of Titebond III before it was primed and painted. But after only a few years of exposure to sun and snow, the marine plywood had begun to check. My conclusion: Titebond is not an adequate substitute for epoxy as a sealer, at least not on my boats.
After some heavy sanding to remove the worst of the checking on the dodger top, I used polyester landscape fabric and epoxy to reseal the weather side -- another experiment to reduce costs by using it instead of glass fabric. The polyester fabric was cheap, but it was too light and rucked up instead of lying flat. I also stiffened up the fore/aft strength by epoxying cleats around the perimeter.
The outboard is one of my good old 1965 Evinrude 6-hp “Fisherman” outboards. The burned-up red gelcoat on the Cutter's topsides was sanded and primed and then roller-painted (no tipping) "work boat grey" -- one can of Rustoleum grey mixed with one can of white. The "window" is another mock-up.
Even with the beefing up and epoxy-fabric coating, the dodger top is still light, easy to lift, and the two oak struts are strong enough to support the dodger until the side panels are attached. With the struts constraining the motion to fore-and-aft, the top is always in control until the side panels are locked on. And because of the built-in camber, it’s also stiff and strong enough to support a couple of small solar panels that I will use for battery charging.
At the launch ramp it only takes a few minutes to raise or lower the hardtop. There are four screws that secure it. And when it is down, it covers the cockpit and cabin hatchway. It's high enough that I don't have to stoop when I'm standing in the cockpit, and there's enough clearance that stepping into the boat from the dock has not been a problem. However, it will be nice to have some handholds either on the top or the side.
So, you can see that I got the mini-trawler built and painted and down to the Bay by the end of October -- the leaves are still on the trees on the Bush River. No bad, not bad at all. And it didn't leak...
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