Abstract: An improved chopper arrangement for use in recovering and allowing the recycling of chopped metal products such as steel, aluminum, copper as utilized in electric transmission lines as well as the recovery of insulation materials thereon. The chopper contains a rotor mounted for rotation within a housing. The rotor has a plurality of rotor cutting blades thereon which pass in wire chopping relationship to at least one fixed blade mounted on a cartridge coupled to the housing. The fixed blade or cartridge cutting blade and the rotating blades or rotor cutting blade are generally rectangular in cross-section. Each of the rotor cutting blades is clampingly mounted on the rotor to allow comparatively rapid movement of the rotor cutting blade towards and away from the cartridge cutting blade to accommodate for wear of the blades and/or differences in the material being chopped.