In contrast to the other rib strips made from poplar wood, the strips of the lowest rib are made from laminated spruce. This means building a mould, planing spruce laminates, stretching them over the mould, and gluing them together, then discarding the mould. The part fits absolutely perfectly. The gluing process also takes some practice – not enough glue won’t hold, and too much creates a mess. There's still room for improvement in this regard.