Design Contest Entries  


Duckworks/Small Craft Advisor
- Design Contest #7 -

Class IV Everglades Challenger

ENTRY #5

Everglades Challenger

click to enlarge
click to enlarge

After much thought, it is finally time to pick up my computer and type in my words and, oy veh! today is the deadline! What follows is a sketch, not the detailed plans that I would build from.

This entry consists of this text file, and an acrobat file with an initial rough sketch giving a general idea of the boat’s shape.

Quick stats:

  • Length: 16 feet
  • Beam: 40 inches (3 1/3 feet)
  • Hull Depth: 2 feet
  • Empty weight: 160 to 200 pounds
  • Cruising weight: 400 to 500 pounds
  • Sail area: 100 sq. feet (or thereabouts)
  • Sail controls all lead to the cabin.

Construction materials:

  • Hull: 3 mm (1/8 inch) plywood, with canvas on the exterior, stitch and tape
  • Keel: 1x12 16 feet long
  • Masts: 2 inch aluminum tube 12 feet long, keel stepped, can also be 2 inch wood poles
  • Sails: canvas or Tyvek
  • Optional, though recommended: waterproof foam for flotation inside
  • Ballast: none, heavy items to be secured as low as possible
  • Alternate propulsion: oars for windless conditions, maybe a yulow for slower, harder conditions.
  • Interior: mostly taken up by a sleeping / living area, with a tiny stove and kitchenette along with other supplies tucked away in one end. Also included small personal hygiene supplies.
  • Cabin construction: open cockpit with a cockpit coming designed to take a canvas dodger for warm conditions. If built where conditions often cold and wet, recommended that a cabin be built with sitting headroom, 40 inches for normal people.

Longer description:

Though the contest is specifically for a boat to enter the Everglades Challenge, the boat described in this brief is actually a fair weather micro cruiser for a single person to gunk hole in sometimes shallow and narrow waterways, where the wind is sometimes blocked off by buildings or trees, where the boat can be beached, and brought up and launched from a beach by a single individual. In other words, these are the same conditions as exist for the Everglades Challenge.

The idea is to have a light weight, easily driven hull with a low, split rig on two masts to reduce heeling, then to make it as simple as possible to operate for a single sailor (actually, I’m so slender that two people my size can fit in it). The reason for easily driven is because I do not expect that there will be sufficient wind all the time for sailing, so the plan is to include a couple of oars and at a comfortable pace, one should be able to row the boat at between four to five knots. I assume that when the oars are used, there is no wind.

What I settled on is a 16 foot long (two sheets of plywood) by 40 inch beam boat with a rig based loosely on that of the recently built megayacht Maltese Falcon, though on only two masts. The construction of the hull will be out of 7 sheets of 3 mm (1/8 inch) exterior plywood for the hull, with 16 foot long 1x12 (cut out to shape) for the keel with the scrap left over from both the keel and the plywood should be sufficient for all the little details of the boat such as two bulkheads, storage bins, and so forth. The exterior of the hull will be finished with a layer of canvas embedded in paint (I don’t think epoxy is needed, but others may use epoxy instead). I figure the completed but empty hull should weigh about 160 pounds. If I add waterproof foam for flotation, that may bring the total empty weight up by 20 to 40 pounds, to a total of 200 pounds. In cruising mode, including stores, battery, stove, crew, etc. should bring the total up to about 400 to 450 pounds.

Construction is basically that of a monocoque structure, with each part helping hold its neighbors in shape and place, resulting in a light weight though rigid hull that needs a minimum of internal frames. The deck is arched between the bulkheads, while the curve for the upswept bow and stern requires a different shape. Plywood cannot take the complex shapes to combine the two into one smoothly curving shape.

The design is that of a decked sailing canoe. It will have identical fore and aft sections. The depth of the hull will be only two feet, which is not sitting height for a normal adult, so for at least 4 feet of the cabin should be higher, 40 inches for at least part of the way. How that raised top of the cabin is to be accomplished will vary by how and where the boat is sailed: if it is sailed mostly in warm and mostly sunny conditions, that raised top can be a canvas dodger that can be folded out of the way when it is not needed. But if it is sailed in an often cold and rainy area, one option may be to have a low, slightly raised cabin, topped by a plexiglass dome. For the Everglades Challenge, the canvas dodger will be used.

I am not as sure about the weights of the masts and rigging, not even the size. Once I crunch some numbers, the final shape and size of the sails will be determined; the sails look like they may be too large as pictured in the accompanying acrobat file with the drawings. They will be a cross between a Chinese junk rig and a square rig, with a somewhat eliptical shape. Reefing will be according to the Chinese junk rig practice, just lower it panel by panel. But the sails will be trimmed as on a square rigged ship. One advantage of the square rig, is that it is possible to connect the two rigs in such a way that trimming one mast will automatically trim the other to the same angle. I plan to have all controls to lead to the cabin I am not so sure about the weight of the rig, but I don’t think it should add no more than about 50 pounds to the total weight above.

The interior will consist of a “cabin” that is 8 feet long by the width of the boat. It will be closed off on both ends by waterproof bulkheads accessible only by hatches on the deck. Because I anticipate using such a small boat only for river, lake, coastal cruising that may include an occasional short jaunt at most a couple of days, so there should be no reason to access those areas when underway. One thing that can be stored in those areas is wheels to make it easier to bring the boat up on shore.

The layout of the interior of the cabin is of necessity simple. Most of the area will be taken up by sleeping / living area. The best is to design the sleeping area to extend to one of the bulkheads. For most comfortable sleeping, the bed should be slightly longer than the crew is tall. The remaining 1 1/2 to 2 foot section will have cabinets to hold the kitchenette, enough stores for a few days, and other odds and ends so necessary for comfortable living.

In closing, what I have presented here is not a boat specifically designed for the Everglades Challenge, rather a very small cruiser that can be used in the Everglades Challenge.

SAILS

EPOXY

GEAR