http://www.ApogeeRockets.com - We're building the Apogee Components Saturn 1B model rocket here. You'll now finish up the shoulder for the LEM Transition by gluing the tube coupler to the rings. When the glue is completely dry, you'll sand off the edges to achieve a perfect fit. Then put super glue on the edges of the rings to keep them from fraying when you put the part into the rocket tube.