Disclosed is a molding device for a machine for manufacturing containers, including: two half-molds; two mold carriers, each of which is provided with a recess for receiving a corresponding half-mold; and at least one retractable attachment bolt that is slidably mounted in at least one mold carrier between an operative position, in which the bolt is extended to removably attach the corresponding half-mold in a clampingly mounted position against the back wall of the corresponding recess, and a retracted position, in which the bolt releases the half-mold, characterized in that each bolt and/or the corresponding half-mold include a clamping strip that is angled so as to cause the half-mold to bear against the back wall of the recess during the sliding of the attachment bolt from the retracted position thereof to the operative position thereof.