A shredder has a jam proof system with a thickness detector having a contact member which displaces as an article is inserted into the shredder and a resistance generating mechanism which provides a resistance force to the contact member, in response to its displacement. More specifically, the present invention provides for a composite enterocystoplasty procedure using a biocompatible scaffold and minced autologous tissue for implantation in a mammalian bladder. Additionally, the foam may create a foam rib between a stud and the casing to support the stud and transfer the stiffness of the stud to a wall of the casing. If the alternate configuration will result in decreased performance, the antenna system is changed back to the first antenna system configuration. A weld is formed along a distal end of the disc lip to secure the wheel disc and rim together. The electron beam may be converted to an x-ray beam which is then processed in the manner described above.