Design Ideas
For design inspiration I began looking at small fiberglass cruising boats. I have always admired Ranger tugs, especially the older models (www.rangertugs.com/previous-models-1.aspx), for their looks and sea-keeping abilities; but the smallest Ranger is 21-feet in length. The C-Hawk Sport Cabins (chawkboats.net/welcome-2/product/222-sport-cabin) are also very appealing. William Least Heat-Moon, author of the epic “Blue Highways,” re-crossed the United States a few years later (“River Horse,” Penguin, 2001) using canals and rivers in the east and then following the route of Lewis and Clark in “Nikawa”, a 22-foot C-Dory (www.c-dory.com/boat/22-cruiser). But these examples were all more complicated than what I had in mind, and much bigger than the hull that I had to work with. Though all of these bigger boats are towable, launching them single-handed would be significantly more difficult. And, as every small boater knows, bigger boats cost more money to maintain, operate and tow.I next looked for cruising boats that are smaller and simple to build, but the closest designs I could find were Paul Fisher’s 16-foot Whooping Swan (www.duckworks.com/product-p/sel-16whoopingswan.htm) and Karl Stambaugh’s classic, Chesapeake Bay-inspired 18-foot Redwing (www.cmdboats.com/rw18.htm) which has a cabin and an aft helm station.
I took rough lines off the Cutter hull and started sketching up several cabin designs. I started with a small cuddy cabin, one berth and sitting headroom for overnight cruises -- enough to get out of the weather. And I wanted a hard dodger for shade and more living space. The hard top would also be an excellent place to mount a couple of solar panels for battery charging. The Cutter’s tailfins were a design challenge because nothing I looked at had anything like them. But simply cutting them off would just make more work and add expense. Since all of my outboard motors have pull-starters, it made sense to stay close to where the motors are and design a clear, simple aft cockpit -- similar to a sailboat -- instead of the more common forward helm on powerboats.
Eventually I carved an inch-to-the-foot solid model of the 14-foot Cutter’s hull to get a better feel for the design. After several iterations of drawings, I built a cabin and dodger from card stock that mated to the hull model. For a sense of scale, the dodger top, shown below, is 4-½ feet long. The cabin is six feet in length, and there are about two feet under cover at the helm station. It’s about 4 feet from the rear cabin bulkhead to the transom. That’s a lot of cabin for a small 14-foot boat, but it all seemed to work in 3-D. And I thought that the cabin-trawler combo looked pretty salty, just like a working boat should.
In designing the cabin and cockpit dodger, I tried to base the dimensions on full sheets of plywood. The side “strakes” are approximately eight feet long. Similarly, the width of the cabin top is about four feet. While the model above shows the cabin top assembled from three planks, it will be quicker to build the top as one piece, with a slight bow. Curves in the plywood, like those in the cabin top, greatly stiffen the sheet. And the cabin sides have a slight bow, from top to bottom, once the cabin top supports pull them in. I drew many versions of the hard dodger, some with side windows, some without. For me, sketches, plans and models are the starting point and a building guide, but the actual construction requirements -- the materials at hand and my more-developed, real-sized needs -- dictated many of the final design elements that I built.
Propulsion
Although I only put enough detail into the model to flesh out my sketches, I planned to hang at least two low-power outboards on the transom. Why carry more than one? My wiseguy answer: The last time I visited the power boat show down in Annapolis, the coolest-looking boats had at least four outboards hanging on the transom. And if you think that boat is a bit over the top, I just watched some video from the Miami boat show which highlighted a 56-foot Cigarette with six 450-hp outboards (www.youtube.com/watch?v=ZMLa7pdd1T4).
As a result of Federal regulations to improve water quality, 2-cycle outboards began to be replaced in the 1980s with 4-cycle motors that have better fuel efficiency and lower pollution. When I retired I brought my car tools down to the Bay and began to work on old outboards instead of old cars. The “bible” that got me started was Max Wawrzyniak’s book, “Cheap Outboards” (Breakaway Books, 2006). I’ve worked on a bunch of antique outboards -- Johnsons, Evinrudes, Neptunes, and Caille; and I have my own collection of post-war outboards. And the auxiliary power on my sailboats are “vintage” 2-cycle outboards that are reliable and easy to service. Even though they might be less efficient than modern 4-cycle outboards, they are low-cost and low impact -- I burn less than 10 gallons of fuel during a typical season. And since the mini-trawler will only be used for occasional cruises, I don’t anticipate using more than a few extra gallons of fuel per year.
Good old outboards are easy to service and keep running. And parts for 50-year old Evinrudes and Johnsons, such as ignition points and water pump impellers, are still available and low cost. In contrast, when an ignition module on a 4-cycle outboard fails, even though it’s a rare event, it fails catastrophically -- there is no “limp home” mode. Assuming you can even find a replacement, it will be expensive. Note that all outboards, old and new, are still dependent on regular impeller replacement (the rare exception is the smallest air-cooled Honda). It’s easy for me to carry spare spark plugs and a set of points, an impeller, and even a spare rebuilt gearbox/water pump when I’m far from home. Of course, every boat still needs some form of back-up propulsion, and the mini-trawler is small enough and will be light enough to be sculled effectively with a yuloh (for info, see Ben Fuller’s articles, e.g., in "Messing About in Boats," Vol. 17, Issue no. 14 and 15).
Although I only put enough detail into the model to flesh out my sketches, I planned to hang at least two low-power outboards on the transom. Why carry more than one? My wiseguy answer: The last time I visited the power boat show down in Annapolis, the coolest-looking boats had at least four outboards hanging on the transom. And if you think that boat is a bit over the top, I just watched some video from the Miami boat show which highlighted a 56-foot Cigarette with six 450-hp outboards (www.youtube.com/watch?v=ZMLa7pdd1T4).
As a result of Federal regulations to improve water quality, 2-cycle outboards began to be replaced in the 1980s with 4-cycle motors that have better fuel efficiency and lower pollution. When I retired I brought my car tools down to the Bay and began to work on old outboards instead of old cars. The “bible” that got me started was Max Wawrzyniak’s book, “Cheap Outboards” (Breakaway Books, 2006). I’ve worked on a bunch of antique outboards -- Johnsons, Evinrudes, Neptunes, and Caille; and I have my own collection of post-war outboards. And the auxiliary power on my sailboats are “vintage” 2-cycle outboards that are reliable and easy to service. Even though they might be less efficient than modern 4-cycle outboards, they are low-cost and low impact -- I burn less than 10 gallons of fuel during a typical season. And since the mini-trawler will only be used for occasional cruises, I don’t anticipate using more than a few extra gallons of fuel per year.
Good old outboards are easy to service and keep running. And parts for 50-year old Evinrudes and Johnsons, such as ignition points and water pump impellers, are still available and low cost. In contrast, when an ignition module on a 4-cycle outboard fails, even though it’s a rare event, it fails catastrophically -- there is no “limp home” mode. Assuming you can even find a replacement, it will be expensive. Note that all outboards, old and new, are still dependent on regular impeller replacement (the rare exception is the smallest air-cooled Honda). It’s easy for me to carry spare spark plugs and a set of points, an impeller, and even a spare rebuilt gearbox/water pump when I’m far from home. Of course, every boat still needs some form of back-up propulsion, and the mini-trawler is small enough and will be light enough to be sculled effectively with a yuloh (for info, see Ben Fuller’s articles, e.g., in "Messing About in Boats," Vol. 17, Issue no. 14 and 15).
My intended purpose of this vessel is to cruise on the bay, on canals, and maybe even in near-coastal areas, such as Core Sound. For cruising on the Erie Canal, with a 10 mph speed limit, one small outboard is plenty of power on a 14-foot boat. But to get the boat to plane I will need more power -- at least two 6-hp outboards if I keep the loaded weight down to a minimum. My actual reasoning and rationalization for twin motors is that the youngest small outboard that I have was built in 1969. With airplanes, more than one motor is a safety feature. So I’ll carry at least two -- and maybe three -- outboards for varying sea conditions and redundancy (and for that Miami Vice look). Short-shaft 6-hp Evinrudes weigh about 50 pounds, so swapping out a motor, even on the water, is not that difficult, in contrast to the Yamaha 350s shown above. For the boat designer, imagine the challenge of trying to balance the 3,000 pound weight of those four outboards on anything less than 30 feet of hull.
If you read this and think that I'm crazy to put more than one little outboard on a small boat, then take a look at this YouTube video...https://www.youtube.com/watch?v=RkVJBw7Vgyk. I like it!
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