This is a pretty rough basic tutorial on achieving concave shapes in sheet metal using a hammer and a stump. This video shows a few techniques including shrinking (sometimes called dishing),sinking, and a glance at raising. Sorry I don't stop and explain terminology as I go I just show how a shape is produced from start to finish in a rather free-flowing manner. Enjoy.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.