Depositing metal as the result of a pass. Bead forming is basic to the metal arc process, and is usually the first exercise for the beginning welder. The object of bead forming is to make all of the electrode material flow into the crater or weld pool produced by the arc. To do this successfully, it is necessary to keep the arc just ahead of the metal which has been deposited, i.e, on the advancing edge of the crater. An examination of the beads will show whether the operator is using the correct current and arc length. An excess of heat will cause the arc to produce a larger crater than the deposit will fill, leaving a small crevice along the edge of the bead. Holding too long an arc will cause the deposit to overlap excessively on the parent metal without achieving proper penetration.