I''m a jewelry student and I''m practicing the gypsy setting. For a 5mm stone, I''m using a 5mm ball bur and the stone stays in, but the setting looks mangled with all the burnishing I have to do. Should I be using a 4.9mm ball bur??? What am I doing wrong?
Cut the hole with a cone bur. Cut the seat with a #52 round graver or a hart or spearhead bur. Personally, I like gravers better because it gives you more control but most students haven't practiced much with them and burs seem easie. Skill with gravers is worth the practice and this is as good a task as any to start with.