First thing is to make the banjo pot, body, call it what you will. It's a simple wooden ring consisting of 16 sectors, each 55mm long. There is no need to round it off, in fact the polygon shape is better.

I began by making a simple mitre jig (11.25 degrees) and slicing off 16 pieces of the sapele strip, each 5.5mm long (longest side).

With the sectors cut, the trick is to glue them up accurately.
Lay them out in a row with the 'inside' of the ring downwards and lay a piece of sticky tape along the row (make it overlap at one end but not the other). This makes it easy to form the ring and complete it by joining the tape.

Start with a dry run. Form the ring and check that each sector meets accurately with its neighbour and that the ring is actually round. This is helped by cutting a pair of sticks exactly the same length and just the right size to fit inside the ring as a cross brace.

When you are happy it all fits, Open the ring and turn it over so that the 'V' of the glue edges are accessible and apply some wood glue to each sector glue edge.

Pick up the ends and join the ring again.

Now you need to put some real pressure on those joins. This is where the rope comes in, we use it as a tourniquet. Take a couple of turns of the rope around the outside of the ring, form a simple half knot so that when you tighten the rope it will trap itself, then put your foot on one end of the rope and haul on the other.

Now is the time to put those sticks back in place so that the ring remains round under pressure. Take another turn, another half knot, and haul again. Try to get an even coil of rope from one edge of the ring to the other to get an even pressure across the whole joint. One of the sticks will probably fall out - it doesn't really matter. Leave it a day or two for the glue to set. Meanwhile, It's time to make the neck.