A clinker dinghy is made up of a number of planks each side; the number of planks is determined by the size and shape of the vessel. A clinker plank is overlaid the plank below for a lap (clinker is also known as lapstrake construction, as strake is another name for a plank and lap describing the joint between each plank).
Each plank is joined through the lap, and it tends to make a very strong and light structure which is ideal for boat construction. The joint usually is not caulked especially on the small dinghy. So ‘watertightness’ relies on a good lap between planks and it being well fastened.
There are different ways to finish each end of a plank in clinker hull construction; for example the full thickness of the plank could run into the stem or transom. However, usually the plank’s thickness is reduced so that the planks become flush at the stem or transom. This is known as a half lap (half the thickness is removed from the bottom edge of the top plank and the top edge of the bottom one, hence half lap). This type of joint is also known as the geralds.
This technique in constructing a hull has been successfully used for quite large vessels (Viking long boats for example), however, it tends to be limited to smaller vessels today. It makes light, strong and pretty dinghies.
The skill demonstrated will focus on preparing the existing fitted plank for the next one, sorting the stem and the transom. Then preparing the next plank, fitting and fixing it into position. All this will happen on a small sailing dinghy (14’ clinker Fowey River sailing dinghy).
The process is demonstrated in the accompanying video clips with a step-by-step guide. The conversation with the boat builder, in this case Marcus Lewis, is unscripted and covers the technique from his experience.