When processing coated aluminum sheet, the fiber core plays a significant part in the cost effectiveness of the end product. The fiber core can either lead to significant losses due to rework or scrap if not designed correctly for the process application. This paper uses the decision made in 1996 to convert to HSM-l fiber cores for the tight-line slitters at Warrick Operations to convert the material produced off the Warri??k Super Slitter back to the regular strength fiber core. A description of slitting and winding theory is included in the paper. This helps support the conclusion that through the utilization� of a looping pit, that the Super Slitter is able to deliver a more consistent rewind tension across the face of the mandrel. This in tum lea??s to the ability to reduce the strength requirements of the fiber cores used on the Super Slitter in tum reducing the processing cost of the E Coat material.