Bottom knives are used in pairs with Top knives Dished knives. The bottom knife is located on the lower shaft compared to the top knife. The main principle for a bottom knife is to position the material web and stretch it for the top knife to cut it. In addition, the bottom knife should “regrind” the top knife when it comes in contact with the top knife. Therefore it is absolute imperative that the bottom knife is angled correctly. Without a correct angled bottom knife the knife pair will not perform satisfactory.