Design Brief & Intent
The core mission of the Cal 35 Cruise Ketch was to provide a comfortable, dry, and liveable home on the water for long-term cruising couples and families. Unlike its contemporary rival, the sleek and narrow-stern racer-cruisers of the early 1970s, this design prioritized interior volume and load-carrying capacity. Lapworth achieved this by pairing a generous eleven-foot beam with a relatively long waterline and a distinctive raised trunk cabin. This high-profile deckhouse features nine large, high-visibility windows that flood the main salon with natural light, directly countering the dark, claustrophobic "cave" feeling common to traditional cruising boats of the era.
Below deck, the interior layout reflects a highly practical cruising mindset. The joinery relies on warm teak veneers and solid teak trim, constructed to a high structural standard that holds up well over decades of use. The galley is situated to starboard, providing excellent security for the cook when underway, while a large, comfortable C-shaped dinette is located to port. A proper sit-down navigation station stands ready for passage planning.
The primary accommodation is split to maximize privacy. The forward V-berth is long and wide, served by an ingenious "Jack-and-Jill" style head layout. Three separate doors allow private access to the head from either the forward stateroom, the main salon, or the walk-through area. Aft, a dedicated starboard quarter berth provides a secure sea berth for watchkeepers close to the companionway, while an abundance of hanging lockers, deep bins, and under-sole storage compartments are integrated throughout the vessel.
Variations & Configurations 5
While the sloop configuration was standard, the ketch-rigged variant of the Cal 35 Cruise was a highly popular factory option. The ketch rig splits the sail plan into smaller, more easily managed components, reducing the physical strength required to hoist and trim the sails. This was especially appealing to short-handed cruising couples of the 1970s before the advent of modern mechanical furling systems.
Under the hood, the standard propulsion package was a heavy-duty, fresh-water-cooled Perkins 4-107 or 4-108 marine diesel engine delivering approximately 50 horsepower. Power is delivered via a V-drive transmission—often a robust Borg-Warner Velvet Drive unit—allowing the engine to be tucked away beneath the cockpit sole.
Crucially, the boat was equipped with immense tankage capacities that lean toward those of a motorsailer. To facilitate long-distance cruising through areas with limited infrastructure, such as the Sea of Cortez or the Bahamas, Lapworth designed the boat with roughly 170 gallons of fuel capacity split between two aluminum or steel tanks. Paired with a fuel-efficient Perkins diesel, this arrangement grants the Cal 35 an extraordinary motoring range of up to 1,000 nautical miles under power alone, a specification practically unheard of in modern 35-foot sailing yachts.
Sailing Performance & Handling
Evaluating the engineering ratios of the Cal 35 Cruise Ketch reveals a boat designed for predictable motion and absolute seaworthiness rather than light-air agility. With a displacement-to-length ratio of 281.79, the hull sits firmly in the moderate-to-heavy displacement cruising category. This weight, combined with a comforting motion comfort ratio of 31.02, means the hull behaves beautifully in a seaway. It slices through steep coastal chops and ocean swells with a smooth, dampening motion, preventing the quick, jerky accelerations that cause crew fatigue on long passages.
The sail-area-to-displacement ratio of 15.86 speaks to a conservative, safety-first sail plan. In light winds under 10 knots, the ketch can feel underpowered and sluggish, often requiring the iron sail to maintain progress. However, when the breeze builds to 15 knots and beyond, the design comes alive. The ketch rig allows for exceptional balance; when wind speeds rise, the crew can simply drop the mainsail and sail comfortably under "jib and jigger" (headsail and mizzen). This configuration keeps the center of effort low and well-balanced, minimizing weather helm, reducing heel, and keeping the cockpit remarkably dry.
With a ballast-to-displacement ratio of 33.33 percent, the boat carries 5,000 pounds of encapsulated lead ballast low in its shallow-draft fin keel. This yields a highly reassuring capsize screening ratio of 1.78, well below the traditional ocean-passage threshold of 2.0, confirming its inherent safety and resistance to roll-overs in extreme conditions.
At 4.67 feet, the shoal-draft keel allows the boat to slip into shallow anchorages that are off-limits to deeper-draft cruising yachts, yet it retains enough lift to hold a reasonable tack when clawing upwind. Steering is remarkably responsive and light compared to full-keel cruisers of the era, thanks to Lapworth’s signature deep-spade rudder. The separate rudder provides excellent maneuverability when backing down under power in tight marinas, mitigating the dreaded "prop walk" typical of traditional full-keeled hulls.
Known Issues & Triage
Decades after leaving the Costa Mesa factory, any Cal 35 Cruise Ketch will present age-related maintenance challenges that require a discerning eye during a pre-purchase survey or ownership triage.
- Bulkhead Rot and Chainplate Leaks: The most critical structural vulnerability is the deck-mounted chainplate system. The stainless steel chainplates pass through the deck and are through-bolted to marine plywood bulkheads. Over time, the flexible sealant at the deck level dries, cracks, and fails, allowing rainwater and saltwater to seep down. This water runs silently along the chainplates, eventually rotting the core of the plywood bulkheads behind the cabinetry. If left un-triaged, the structural integrity of the rig is compromised. Any soft wood or discoloration around the chainplate attachments requires immediate bulkhead replacement or reinforcement.
- Deck Core Wetness: The deck and cabin house are constructed with a balsa wood core sandwiched between fiberglass skins 5. Countless deck hardware installations—such as stanchion bases, handrails, cleats, and the main mast step—are potential paths for moisture. A thorough hammer-sounding or moisture-meter scan of the deck is necessary to identify soft spots or delamination, particularly around the forward cabin top and the side decks.
- Mizzen Mast Step Compression: On ketch-rigged models, the mizzen mast is stepped directly on the deck above the aft cabin. Decades of rig tension can cause the cabin house roof beneath the step to compress if the internal support posts or deck reinforcement have deteriorated from rot. Look closely for cracks in the fiberglass or sagging in the cabin overhead directly under the step.
- Fuel Tank Corrosion: The massive original dual fuel tanks are made of aluminum or steel and are located deep below the cabin sole. Bilge water contact and trapped condensation can cause pinhole corrosion and eventual fuel leakage. Replacing these tanks is a major labor-intensive project, as it often requires cutting out sections of the teak cabin sole and interior cabinetry.
Modernization & Upgrades
Many surviving examples of the Cal 35 Cruise Ketch have undergone extensive modernization by owners determined to preserve these robust hulls for another generation of voyaging.
- Composite Bulkhead Reconstruction: When addressing rotted chainplate bulkheads, veteran owners are increasingly bypassing standard plywood in favor of advanced composites. High-density polyurethane foam panels reinforced with fiberglass (such as Coosa board) are used to rebuild the structural bulkheads. This material is completely impervious to water, ensuring that any future deck leaks cannot cause rot.
- Repowering: While the original Perkins diesels are legendary, parts sourcing is becoming more challenging. Modern refits frequently involve repowering with more compact, quieter, and highly efficient modern diesels. Engines from Beta Marine or Yanmar in the 40 to 50 horsepower range are the most common choices.
- Solar and Off-Grid Electrical Systems: The expansive deckhouse and wide cockpit of the Cal 35 provide an ideal canvas for solar integration. Owners frequently install custom stainless steel arches over the stern or rigid fiberglass hard dodgers to support solar arrays of 400 to 600 watts. These systems are typically paired with modern Lithium Iron Phosphate (LiFePO4) battery banks, which are lighter and can be easily stowed in the dry lazarettes.
- Opening Port Conversions: The original fixed windows on the trunk cabin can be prone to leaking and offer no ventilation. Replacing these with modern, aluminum-framed or heavy acrylic portlights, alongside replacing original forward ports with opening Lewmar units, significantly improves both cabin airflow and dry-boat reliability.
The Verdict 2
The Cal 35 Cruise Ketch is an exceptionally robust, spacious, and sea-kindly cruising boat that successfully brings the comfort and capability of a larger motorsailer down to an accessible and easily handled 35-foot platform. It is a vessel built for the patient cruiser who values heavy-weather security, remarkable interior volume, and unparalleled long-range tankage over racing speeds. Provided the classic structural areas have been surveyed and properly repaired, this classic Lapworth design remains one of the best values on the brokerage market for couples wanting to go the distance in comfort.
- Tremendous interior volume with a bright, open raised-cabin layout that provides exceptional light and ventilation.
- Colossal fuel capacity (170 gallons) providing an unmatched motoring range of up to 1,000 miles.
- Highly manageable ketch rig allows for versatile sail configurations and easy short-handed handling in heavy weather.
- Extremely comfortable, sea-kindly motion in rough offshore conditions, backed by solid hand-laid fiberglass construction.
- Excellent maneuverability in close quarters due to a responsive spade rudder and a shoal-draft fin keel.
Cons
- Poor sailing performance in light-air conditions (under 10 knots of wind), requiring motor-sailing or auxiliary power.
- High risk of hidden structural rot in the plywood bulkheads around the chainplates.
- Potential for costly deck-core delamination and mizzen mast step compression.
- Difficult access to the fuel tanks beneath the cabin sole if replacement or repair is required.
