Off-center curls are performed in 3 strokes in die set F110-F111 and on-center curls in 4 strokes. On-center curls will not be perfectly round unless a mandrel is used in the last operation. Curls may range in size from 1/4" inside diameter to 3/4" inside diameter in 16 gauge and lighter. The range can be increased slightly if a mandrel is used.