Abstract: Apparatus for compressing an elongated strip of resilient material and inserting the strip, together with a flexible membrane, into a channel member supported on a substrate wherein the apparatus includes a frame assembly, supporting and moving structure for the frame assembly; pairs of converging roller assemblies for receiving and temporarily elastically deforming the strip of resilient material into an inverted V-shape; a grip wheel for gripping the apex portion of the inverted V-shaped strip and pushing at least a portion thereof, together with abutting portions of the flexible membrane, into the channel member; and a pressing tool for inserting the strip fully into the channel member and thereafter returning the strip to approximately its natural shape to thereby frictionally retain adjacent portions of the flexible membrane within the channel member.