In traditional boatbuilding copper nails and roves (washers) are used to make rivets, in order to fix the overlapping planks in clinker planking, and as fixings for the various parts of the structure of a boat. Before copper, iron nails were used, and the ‘clink, clink’ of iron nails being hammered home is said the to be the origin of the term clinker.
A copper nail is hammered through a pre-drilled hole, and a rove then hammered over it, using a rove punch, which has a hole drilled in its end to accommodate the nail. To prevent the nail being pushed backward, a metal ‘dolly’ is held against the head of the nail – this is generally a two-person job! Once the rove/washer is tight against the inside surface, the excess nail is snipped off just above the top of the rove. The ball end of a ball-pein hammer is then used to mushroom the end of the nail, over the rove/washer, thus forming a rivet. Again, a dolly is used to ensure that the head of the nail stays tight to the outside surface. The dolly has to be of sufficient weight to counteract the force of the hammer during roving (clenching down the washer) and peining over the nail.
I have made myself a roving kit, using various sized pieces of mild steel. There are two roving punches, the central holes are sized for the two different diameters of nails I will be using. (I plan to ‘countersink the bored punch holes, to match the shape of the washers to be used.).
The dolly has to be of sufficient weight to counteract the force of the hammer during roving and peining over the nail.
Standard size copper nails are still available from a few suppliers. However, one cannot readily obtain the longer thicker nails required for the heavier fixings required to make the stem and fit the transom knee. So, I made a former and, using some 5mm copper rod, produced some home-made copper nails.
There’s a real joy to be found in making your own tools. Even when I have made the tool required to create a nice smooth crown to the rivet, I will have made this set for less than half the £120 retail price of a new set of roving tools.