Cut your foot long length of PVC into two 6-inch segments. This piece of PVC should be slightly wider in diameter than the pieces you'll be running through the hinge.
Dampen your microfiber cloth with a solvent, such as acetone or rubbing alcohol. Wipe the inside ends, and the entire outer surface, of both hinge pieces clean of all dirt and grease. Also wipe out the outsides of the PVC pieces you'll run through the hinge.
Apply a generous layer of PVC primer to a 1-inch strip along the entire outside length of both hinge pieces. Allow the primer to set for one to two minutes.
Cover the strip of primer with a generous coat of PVC cement. Press the strips of the two pieces together and hold them firmly in contact for five to 10 minutes. Ensure that the edges of the hinge pieces are aligned with each other.
Allow the cement to cure for the time suggested by the manufacturer. Failure to do so may cause your hinge to weaken and separate over time.
Coat the inside ends of the hinge with PVC primer, then allow it to dry for one to two minutes. Perform this step for the outside ends of the pipes you'll run through the hinge.
Apply PVC cement over the primer. Insert two pipes into one side of the hinge. Give each pipe a quarter turn to lock it into place. Perform this step for your two other pipes on the opposite end of the hinge.
Allow the cement to cure for the time suggested by the manufacturer.