Design and Construction
Sharp’s 1976 design combines a fin keel and spade rudder with a 31-foot overall length, a 26-foot-6-inch waterline, and a beam of 10 feet 4 inches. Displacement is near 8,900 pounds, with a ballast ratio of about 27 percent.
The hull and deck are solid fiberglass, finished inside with teak. Yachting Monthly described the Dolphin 31 as well built and finished, consistent with her reputation as a substantial coastal and offshore cruiser rather than a featherweight racer.
Her wetted surface is roughly 301 square feet, while the immersion rate is about 1,116 pounds per inch. These figures point to a moderately loaded cruising hull that holds her lines without dramatic changes in trim as stores come aboard.
Rig and Handling
The Dolphin 31 carries a conventional masthead rig. Her running rigging follows the cruising norms of the period: jib and genoa sheets about 31 feet long and half an inch in diameter, a 77.5-foot mainsheet, and a 68.2-foot spinnaker sheet, all in 12 mm.
The fin keel draws about 4 feet 10 inches, increasing slightly under load to roughly 5 feet 1 inch. That allows her to tuck into shallow marinas while retaining enough lateral plane to stand up to a breeze.
In service, Yachting Monthly found her to be a powerful seaboat. Owners and testers also noted, however, that she was perhaps not as fast as the lively promise of her profile suggested.
Accommodations
For a boat of her era, the Dolphin 31 is roomy. She sleeps six, with a dinette that converts into a double berth and an unusual pair of quarterberths stacked in two tiers. The galley is large for the period, and the forecabin is well proportioned.
This charter-oriented footprint translated well to private ownership. The teak interior, standard for the time, provides a warm, serviceable complement to the fiberglass structure rather than making a luxury statement.
Ownership Profile
Although the Dolphin 31 was only modestly successful in her intended charter role, a number were sold as solid, fast cruising boats. Since then, they have served first-time buyers well.
Yachting Monthly recommended the boat as an economical all-rounder for first-time buyers. That judgment fits a production run of 55 straightforward, repairable cruisers.
The Verdict
The Dolphin 31 is a thoughtfully laid-out 1970s cruiser with genuine seaboat character and a generous interior for her length. She’s no speed demon, but her construction and accommodations make her a sensible step-up boat for newcomers to cruising.
Pros
- Well-built and finished solid-fiberglass hull, with a teak interior
- Roomy six-berth layout with a convertible dinette and twin tiered quarterberths
- Modest draft for a fin-keel 31-footer: marina-friendly yet seakindly
- Economical all-rounder well suited to first-time buyers
Cons
- Not as fast as hoped, given her masthead-rig profile
- Only modestly successful in her original charter role
