To flatten copper that is buckled, hammer the surface with a light planishing hammer on a bright tinman's anvil, commencing at the end and going backwards and forwards across the metal with a series of regular blows, until the entire surface has been covered. Any hollow places along the centre of the strip must be drawn down flat by hammering from the edge of the hollow out to the edge of the strip. Should the strip be wavy or loose along the edge, hammer along just inside the edge and work back towards the centre of the strip until the edge is drawn flat.