Die sets F116-F117 and F118-F119 should be considered when a highly accurate on-center curl is desired. These dies may be used to produce a curl from 1/4" to 1/2" inside diameter in light gauge material. A minimal flat appears on the lead edge and the sheet remains relatively flat during the forming operation. The sheet to be formed must be wide enough to provide for a reasonable amount of stock to extend in front of the die sets for safe feeding of the part.