Design Brief & Intent
The primary mission of the Sea Devil was absolute portability, extreme cost-efficiency, and user-friendly simplicity. Unlike class-restricted racing dinghies built with traditional hand-laid fiberglass, the Sea Devil was designed from the inside out to be virtually unsinkable. The core of the boat is a solid block of Expanded Polystyrene (EPS) foam, which provides positive buoyancy regardless of hull integrity. For the interior, there is no "cabin" or "fit-out" to speak of—the cockpit is a simple, shallow, open recess molded into the deck shell, designed strictly for wet, warm-weather sailing where the crew sits on the coaming or directly on the cockpit floor. This focus on minimalism meant that first-time sailors could master basic sail trim, helm control, and wind awareness without the mechanical complexity of larger, traditional pocket cruisers.
Variations & Configurations
While the fundamental hull shape remained consistent, the Sea Devil underwent critical material and branding shifts during its production run. The earliest models produced by Siltronics and early Lockley Manufacturing (which purchased the tooling in 1970) featured a protective skin of sprayed polyurethane over the raw EPS foam core. Recognizing the rapid degradation and fragility of this early coating, Lockley transitioned in 1973 to vacuum-forming a rugged ABS polymer skin over the EPS foam—a process marketed as "Armorclad".
In the mid-1970s, as the manufacturer sought to distance the product from negative branding connotations, the Sea Devil was officially renamed the "Sea Skimmer". Under this new moniker, production eventually merged into the Snark Sailboats line following Lockley's acquisition of Kransco in 1984, before ultimately transferring to the Meyers Boat Company in 1996.
In terms of rig, the Sea Devil is uniquely configured as a pocket sloop—sporting both a mainsail (55 square feet) and a small, halyard-raised jib (15 square feet). This configuration sets it apart from its single-sail sister ships, the lateen-rigged Super Snark and the Sunflower, offering a more realistic "big boat" sailing layout in miniature.
Sailing Performance & Handling
On the water, the Sea Devil behaves precisely as its featherweight specifications suggest. Weighing in at a mere 70 pounds, the boat has an incredibly low displacement-to-length (D/L) ratio of 20.55. In physical terms, this ultra-lightweight profile enables the boat to get up and plane easily in moderate breezes on flat water, delivering surprising bursts of speed downwind. However, with a comfort ratio of only 1.93, the boat offers virtually no dampening force against waves; it rides over chops like a leaf, resulting in a highly kinetic and notoriously wet sailing experience.
The capsize screening ratio of 3.15 highlights the boat’s high level of initial tenderness. Lacking any internal ballast, the crew’s body weight acts as the sole righting moment. While capsizing is a common occurrence in gusts, the solid EPS foam core ensures the boat remains floating high, and its low profile makes it incredibly easy to right, even for solo youth sailors. The sloop rig allows the boat to point reasonably well to windward compared to its lateen-rigged contemporaries, though its performance is heavily dependent on the sailor's ability to minimize drift by keeping the wooden daggerboard fully inserted and keeping the hull flat.
Known Issues & Triage
The most significant vulnerability of the Sea Devil is the structural integrity of its outer protective shell.
- ABS Skin Delamination and UV Degradation: Decades of sun exposure cause the vacuum-formed ABS polymer skin to become brittle, crack, and eventually flake off in large chunks. This UV degradation exposes the underlying EPS foam to physical damage and water retention.
- Water Entrainment in Foam Core: While EPS foam does not sink, it can absorb water over time if the outer skin is punctured or cracked. A waterlogged core can easily double the boat's carrying weight, destroying its car-toppable appeal and ruining its planing performance.
- Appendage Decay: The original daggerboard and rudder assembly were constructed of marine plywood. Over years of immersion, these wooden components are highly prone to swelling, warping, and delaminating within the daggerboard trunk.
Modernization & Upgrades
For vintage hulls, owners have developed highly effective triage and refit strategies to keep these classic board boats sailing.
- Fiberglass Skin Conversion: When the original ABS skin completely deteriorates, veteran owners strip the remaining plastic and seal the raw EPS foam core using a lightweight fiberglass cloth saturated with epoxy resin. It is critical to use epoxy, as standard polyester resins contain styrene, which will instantly dissolve the polystyrene foam core.
- Synthetic Appendages: To resolve the swelling issues of the original plywood, owners frequently upgrade to modern, rotationally molded synthetic or high-density polyethylene replacement daggerboards and kick-up rudders, which are impervious to rot and slide smoothly in the trunk.
- Control Line Upgrades: The original layout was bare-bones, often requiring the sailor to hold the mainsheet directly with a hand wrap. Modern refits often involve mounting a simple deck-swivel mainsheet block and small cam cleats to alleviate helm fatigue during longer sessions.
The Verdict
The Sea Devil (and its sibling, the Sea Skimmer) remains a brilliant testament to the simplicity of mid-century recreational design. While it lacks the refined fiberglass construction, speed, and class prestige of a Laser or a Sunfish, it offers an exceptionally low-barrier, unsinkable platform for learning the fundamentals of sailing. For those willing to overlook its plastic-and-foam build quality and its tendency to provide a thoroughly damp ride, it represents one of the most cost-effective and easily transportable pathfinders to the water.
Pros
- Extremely lightweight and easily car-topped on almost any vehicle without a trailer.
- Solid EPS foam core ensures the hull is completely unsinkable, even if severely damaged.
- Sloop rig with mainsail and jib provides an authentic training layout for learning multi-sail trim.
- Highly responsive helm that planes easily in moderate winds.
Cons
- ABS outer shell is highly vulnerable to UV degradation, cracking, and eventual delamination.
- Extremely wet ride with very little protection from spray or chop.
- No interior storage or dry compartments of any kind.
- Original plywood rudder and daggerboard are highly susceptible to rot and warping.
