Ribs are laths that go across the boat from side to side. Stringers are laths that go from front to rear of the boat

Find the centre point of a lath by balancing it on a finger. Lay this lath (rib) across the seat posts, with the centre point over the middle seat post. Do the same with three more laths (stringers), and lay these over the rib with the centre point over the three seat posts. Drill, countersink and screw these laths into the seat posts. It's important that these screws are countersunk - if they are left proud of the laths, you risk puncturing the covering

Bend the rib downwards at each end towards the seat, in a gentle curve. Temporarily affix with G clamps so you can check by eye that the curve on each side roughly mirrors one another. Nail to the gunwale

Flip the boat over so it sits on the workbench on its base. Lay two stringers between the seat posts, on top of the rib, as with the previous stringers. Nail a couple pieces of scrap laths over the stringers, either side of the seat, to the workbench - outer edges approximately 15in (40cm) away from the seat posts at the front of the boat, and 6in (15cm) from the seat posts at the rear of the boat. This will help you form a flatter base, avoiding a rounded base that would cause an unstable craft

Starting with the centre stringer, bend upwards at the front of the boat towards the gunwhale to form a gentle curve. Clamp in place. Repeat at the rear of the boat. Repeat with the four remaining stringers, using your centre stringer as a reference for the curve

Weave a rib in front of the seat posts at the front of the boat, about 4in (10cm) from the first rib. You may need to unfasten/refasten your scrap lath braces. Bend these to the gunwhale, using your first rib as a reference. Clamp in place. Repeat with 2 more ribs at the front of the boat, and one in the rear of the boat

Weave one stringer on each side of the boat, outside your existing stringers. Bend these up the gunwale. These outside stringers may not lie beside their neighbours on the gunwale - mark the bottom of the gunwale, cut the excess and clamp it inside the adjacent lath

Weave more ribs at either end of the boat - totalling 5 in the front, and 3 in the rear. These outer ribs don't need to stick to the 4in (10cm) spacing. You may need to adjust some laths to allow these to lie comfortably against one another

Fit short laths at the corners of the boat, to avoid large, unsupported areas of calico. These diagonals go outside the other laths when looking at the boat from underneath. Their ends on the inside sit on the inside of the laths on the base of the boat

Nail and clench, or staple, all laths in place. Cut off excess laths above the gunwale

With your frame built, you can paint your frame now if you wish. If doing so, you should also paint four extra laths with will form the inner and outer gunwales once the boat is covered