Clinker (boat Building) - Fastenings

Fastenings

The planks may be fastened together in several ways:

• with copper or iron rivets consisting of a square nail and a dish shaped washer called a rove. The land is pierced, the nail knocked through from the outside, the rove punched on while the head is held up by a dolly. The nail is cut off just proud of the rove and the cut end clenched over the rove while the dolly (a small portable anvil, usually of cylindrical shape) is used to hold the nail in place. In planking up clinker work, one man can hold both dolly and clenching hammer. Although this is common where sawn frames are to be used, boats intended for steamed timbers are usually nailed but not clenched until the timbering out is complete. As timbering is a two handed job it is more efficient to leave the clenching until help is at hand then the helper dollies up, whilst the builder sits inside the hull and clenches up.
• with iron nails with the pointed nail ends protruding on the inside of the boat, bent over and back into the wood in the form of a hook. This is a cheap and cheerful technique maybe called clinching in some parts but usually, in England at least, "turnin'-em-over". It is the sort of thing which used to be found in Scandinavian-built boats but even with iron nails, on the lands, they were usually properly clenched over roves. Nails fastening timbers were sometimes turned over, particularly where removable bottom boards were to rest on the timbers. However, it was possible to tread the bottom boards onto the clenched nails and where marks were left, gouge out recesses to accommodate the clenched nails.
• screws were used for fixing the ends of the strakes to apron and transom and in later times, knees to gunwale and thwarts, but traditionally, this last would be done with a clench bolt or a large copper nail, clenched.
• adhesive, notably epoxy. Traditionally, lands were neither glued nor was anything used to bed them. The garboard was bedded onto the hog and keel, and the ends of the strakes onto the stem and apron using a mixture of white lead and grease. During the World Wars new techniques and materials were developed by the aircraft industry. By the mid 1950s, these were well infiltrated into the boatbuilding trade. New boats in classes of racing dinghy with clinker hulls were built as glued clinker boats. The basic construction was the same but ply planking was used and the lands were glued with no fastenings, except that the ends and garboards were still screwed to apron and hog. The need to prevent the splitting of the planks was removed by the use of ply so no timbers were used. Except for a light gunwale and wide rubbing strake, the longitudinals were omitted too. A short thwart rising and knees were glued to the planking. These boats were all decked and that is how adequate stiffness was achieved. So that the liquid glue could be laid onto the land before the next plank was assembled onto it, they were built upside down.