I’ve started with the seat. It’s 2 metres long, and half a metre wide. This width is difficult to manage as one piece of wood, so I make it up out of 5 pieces (staves) that are 100mm wide. This is called jointing.
I make all the staves the same thickness, and then plane the edge of each one so that it is perfectly flat and square. This is so that there are no gaps and the board is flat when I glue them together.
I machine the edges first on a surface planer, but has to be finished with a hand plane to smooth out the tiny ridges that the machine leaves. The thickness of the oak in this photo is 2cm, so the ridges are about half a mm apart.