Conway OD — Information, Review, Specs

W. .H Rowlands·1928·~16 hulls·W. H. Rowlands
Approximate drawing

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Hull type
Monohull · full
Rig
Fractional Sloop
LOA
20' · 6.1 m
Displ.
1,400 lbs · 635 kg
First year
1928

The Conway One Design, frequently referred to as the Conwy One Design (COD), is a storied 17foot6inch classic dayboat born from the challenging tidal waters of the River Conwy in North Wales. Designed in 1948 by Mike ScottPaine, the vessel was engineered to provide a robust, competitive racing platform capable of navigating both the river’s strong currents and the choppy conditions of the open bay. Originally constructed using traditional clinker planking, the class has seen a successful transition into Glass Reinforced Plastic (GRP) while maintaining its strict "one design" ethos. The boat remains a cornerstone of Welsh maritime heritage, characterized by its elegant, highsheer lines and a heavy displacement for its size that provides stability in weather that would ground lighter dinghies.

Measurements

Dimensions 01

LOA
20 ft
LWL
15.83 ft
Beam
6.58 ft
Draft
2.92 ft
Max headroom
-
Air draft
23 ft

Construction & hull 02

Construction
Wood
Hull type
Monohull
Keel type
Full
Rudder
1× Attached
Ballast
-
Displacement
1400 lbs
Water
-
Fuel
-

Rig & sails 03

Rig type
Fractional Sloop
P · main luff
-
E · main foot
-
I · fore ht.
-
J · fore base
-
Forestay (est)
-
Sail area
212 sqft

Calculations 04

SA/D ratio
27.1
Ballast/Disp.
D/L ratio
157.56
Comfort ratio
10.29
Capsize screening
2.35
Hull speed
5.33 kn

Sailing Performance & Handling

The Conway OD is defined by its sea-kindliness and "big boat" feel despite its modest length. With a displacement that is significantly higher than modern racing dinghies of similar size, the COD carries its momentum well through tacks and remains surprisingly dry in a chop. This stability is largely attributed to its heavy galvanized steel centerplate, which weighs approximately 170 lbs. This weight provides a high righting moment, allowing the boat to stand up to its generous sail area without the constant need for extreme hiking.

Handling is described by the Conwy One Design Association as being balanced and predictable. Because it was designed for a river known for its fierce "Conwy Cob" waves and swirling eddies, the rudder is deep and effective, providing the bite necessary to steer out of trouble in heavy air. Under sail, the boat lacks a spinnaker, a design choice intended to emphasize tactical helming and pure sail trim over the complexities of additional rigging. This makes it an excellent trainer for traditional seamanship while remaining a fierce competitor in the local regatta circuit.

The Conway OD is a regional icon, predominantly celebrated in Welsh maritime literature and regional sporting news. While it has not been the subject of major international films, it is a fixture of the Conwy River Festival, an event that showcases the class's longevity and cultural importance to the town of Conwy. The boat is also featured in various historical retrospectives on the development of post-war UK regional classes, often cited as a prime example of a successful transition from wood to fiberglass without losing the class's identity.

Known Issues & Buyer’s Checklist

When evaluating a Conway OD, the first point of inspection is the hull material, as maintenance requirements vary significantly between the classic wooden boats and the newer GRP hulls.

  1. Keelson and Hog (Wooden Models): In older clinker-built examples, freshwater trapped in the bilge can lead to rot in the keelson or the hog. Prospective buyers should inspect the garboard strake (the first plank next to the keel) for signs of "nail sickness" or soft wood.
  2. Centerboard Trunk: The centerboard case is a high-stress area. In GRP models, check for weeping or spider cracks around the base of the trunk. In wooden models, this area is a common source of leaks and may require specialized timber repair.
  3. Centerplate Corrosion: The heavy steel centerplate is prone to rust if the galvanization has worn thin. If the plate is seized or shows significant pitting, it can affect the boat's stability and center of lateral resistance.
  4. Rigging Attachments: The shroud chainplates and the forestay fitting take considerable load given the boat's stiffness. Ensure the backing plates are secure and that there is no deformation in the deck or hull where these fittings are through-bolted.

Community & Resources

The class is primarily supported by the Conwy One Design Association, which maintains the official register of boats and coordinates the racing schedule. The association is the definitive source for technical specifications and class rules, ensuring that even as older boats are restored, they remain competitive within the fleet. Technical support and social history are also frequently preserved through the Conwy Yacht Club, which has hosted the fleet since its inception.

The Verdict

The Conway OD is a masterclass in regional maritime design, offering a blend of traditional aesthetics and rugged performance. While its weight and maintenance needs (particularly for wooden versions) might deter those seeking a modern "plug-and-play" dinghy, its historical value and superb handling in rough water make it a prized possession for enthusiasts of classic dayboats.

Pros:

  • Exceptional stability and sea-keeping for a 17-foot boat.
  • Strong, dedicated racing community and heritage.
  • Timeless, elegant aesthetics that turn heads in any harbor.
  • A "dry" ride compared to modern low-freeboard dinghies.

Cons:

  • High maintenance requirements for traditional clinker-built hulls.
  • Heavy weight makes it difficult to launch and retrieve without a dedicated trailer or crane.
  • Limited availability outside of North Wales and the UK.

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