Cal 31

About the Cal 31

Researched from public sources for this model. Any individual boat may have been modified or repowered — confirm before relying on any figure.

Built

?–1984

Builder

Bangor Punta Marine

Designer

C. William Lapworth

Length

31.5 ft

Waterline

25.67 ft

Beam

10 ft

Draft

5 ft

Displacement

9,170 lb

Ballast

3,600 lb

Hull

fiberglass

Hull / keel

fin keel

Rig

sloop

Propulsion

inboard

Fuel

20 gal

Water

56 gal

Stern thruster

none

Sources disagree on first year — left blank rather than guessed.

Solid hand-laid hull; deck plywood-cored under hardware and cabin top Klegecell-foam cored. Encapsulated lead keel; foam-cored rudder on a stainless stock. Welded aluminum fuel tank, polyethylene water tanks. Earlier boats had Volvo two-cylinder diesels, later a 16 hp Universal. Shoal-draft keel 4.25 ft. Practical Sailor says production began fall 1978 with 130 built in the first three years; start year disputed (see disputed).

Known problems for this model

• Leaking stanchions, chainplates and hatches deck
  Practical Sailor says the most common owner complaints are water leaks at stanchion bases, chainplates and hatches.
  practical-sailor.com
• Hardware lacks metal backing plates deck
  Most deck hardware, including the bow fitting/chainplate, has no backing plate, and backstay chainplates use fiberglass rather than metal backing.
  practical-sailor.com
• Leaky companionway other
  The wide tapered companionway and butt-jointed drop boards let water in; the optional sea hood is recommended.
  practical-sailor.com
• Nylon seacocks and fouled bilge sump plumbing
  Underwater through-hulls use glass-filled nylon ball valves that some owners replace with bronze; the icebox and shower drain to the bilge sump, causing odor and clogging pumps.
  practical-sailor.com
• Vibration and reverse handling engine
  The engine transmits notable vibration to the hull, and backing requires a firm hand to keep the rudder from slamming over; Volvo-powered boats pull hard to starboard in reverse.
  practical-sailor.com

Other Cal models

• Cal 2-27 1974–1980
• Cal 2-29 1974–1978
• Cal 25 1965–1976
• Cal 39 Mk II 1978–1982