PURPOSE: To ensure quality which avoids pitting and inequalities in the surface of a blade by extruding a continuous length of curable elastomer through a die, preforming the continuous length of extruded elastomer to produce a weakened mid-section, then curing the continuous length of extruded elastomer, and thereafter separating it by pulling apart along the mid-section.

CONSTITUTION: A curable elastomer 11 from an extruder 13 is extruded outside through a die 17 having a die orifice. The die 17 includes a die opening 19 which is shaped to produce a pair of wiper blades 21, 13 joined at a mid-section 25 thereof in edge-to-edge relation, and adjusting blades 27, 29 for an adjustable scoring mechanism. The continuous length 11 of extruded elastomer which has been scored at the die 17 is then passed to a curing station and the elastomer is received through a continuous vulcanizer 41. After curing, the continuous length of curable elastomer 11 is separated into lengths of wiper blades 43, 45 by allowing one length blade 43 to travel over a fixed nip roller 47 while the other length blade 45 is pulled under the nip roller 47.