The retaining ring is cut from the same size PVC tube as the mold. A wedge or segment of the ring is cut such that it will fit into the mold tube. Using PVC cement, the ring is glued to the mold tube.
	The rest of the mold tube is covered with the liner (PVC shower pan liner), glued with the same PVC cement.
	A hole the same size as the exit diameter of the nozzle insert is drilled on the end cap which is then glued to the mold tube on the same side as the retaining ring.
	Close up view of retaining ring and end cap.
	Side view of end cap in place
	The inside liner is covered with RTV high temperature silicone.
	The ceramic nozzle insert is covered with RTV high temperature silicone.
	Side view of insert with RTV silicone.
	The nozzle insert is pushed into place divergence side facing end cap until the base of the insert touches the retaining ring. The excess silicone is spread over the juncture ceramic insert, retaining ring, end cap.
	On the convergence side the excess silicone is spread evenly to cover the edge of the insert.
	Axial view of convergence end.
	Axial view of divergence end.
	The PVC coupling is then glued on the convergence side of the molding tube, thus leaving one end open for the installation of the combustion chamber of the engine.
	Completed nozzle assembly.

Notice that the nozzle is assembled on the same PVC tube used as the mold. Because the ceramic insert has already shrunk about 8%, the liner plus the silicone will make up for the difference, help to seal and insulate from the extreme heat the nozzle is exposed to.