Making a Belly Button Using Foldforming

This is a short video of making a 'Belly Button', a kind of round line fold, where a dot of work hardness is formed on a dome and simultaneously a ring of work hardness forms below where the anvil strikes upwards the same way that the planishing hammer strikes from above. As tapping continues the dot and ring push the annealed metal between them forming a 'belly button'. This observation is where the idea for Forming Blocks came from.