Systems and methods for joining two or more pieces of hook fastener tape. In some embodiments, the two or more pieces of tape are spliced together using ultrasonic welding. At least one of the splicing components used to splice the tapes together may be configured so that the component influences the profile of a connecting portion along which the two tapes are welded together. In some cases, at least one of the splicing components may be configured to minimize deformation of the tapes as they are welded together.