Place an annealed
disk of metal in a dapping-block depression that is slightly larger than the disk’s diameter. The disk must not extend beyond the edge of the depression, or it will be marred as you force the metal into the depression. Choose a dapping punch that is slightly smaller than the depression (to accommodate the thickness of the metal).
Set the punch on the disk, and strike the punch with a chasing hammer or mallet until the metal sinks into the depression (see figure at right). Your first blow will make a shallow indentation; each successive blow will carry that indention inward toward the center of the disk.
When the metal conforms completely to the contour of the depression, move the disk to the next smaller depression and switch to a smaller punch. Form the dome in stages until you have achieved the desired size and shape.