Overflow from our readers’ postbag which we didn’t have room to publish in the magazine
Boat construction details
Your 100-point boat tests are informative and of real interest, but a standard table to convey the boat’s design and construction would improve the quality of reporting, which is slightly inconsistent.
For example:
• How thick are the hull and deck? Are they single-skin or sandwich construction? If the latter, what’s the core material?
• Is there a sub-structure – none, galvanised steel or stainless?
• Are the shrouds attached directly to the hull, to a sub-structure or to knees?
• How are the hull and deck joined? If it’s a bolted joint, what are the size and pitch of the bolts? If it’s laminated and sealed or glued, with what?
• What are the bulkheads made of, and are they laminated on both sides? If not, how are they sealed or glued in place?
• How is the rudder built? What’s the core material? If there’s a sub-structure, what’s it made of? What’s the diameter of the shaft, and what material is it?
• What materials are used for the keel bulb, fin and stub? How are these fixed together? How many keelbolts are there, and of what diameter?
• What is the make and size of engine? Does she have a drive shaft – with or without a bearing – or a saildrive?
Your boat tests usually expand on some of these items, which is helpful, as sales brochures are often lacking in this important detail.
A series of articles from surveyors on the integrity of sandwich hulls and decks, and keel and shroud attatchments, after 10, 20 or more years of use would be of great interest. The great majority of boats are now made in this way, saving weight and cost, with some stiffness improvement provided the core integrity and the bond to the core are maintained.
At the Southampton Boat Show, I could find just four single-skin hulls (only one of which had a single-skin deck). One major manufacturer offered only one of its 20 models with a single skin, and this was intended for class racing in a charter role – presumably designed for intensive use. Does this suggest a possible trend back to single skin?
David Morris