If a string breaks in an RV shade, remove the shade, take it apart, and obtain two pieces of cord. Place one cord on each side of the spring, folding them in half and making a loop on the spring. Place the top bar of the shade in its original place, and thread the cords. Thread the cords through the shade, and reassemble the entire shade.
Once you place both cords on the spring, attach the spring to the upper rail of the shade, connecting it in the center with duct tape. Make sure to place the cords in the center of the spring on each side before placing the upper bar of the shade in its location. Be careful not to catch the cords when you slide in the bar. Insert the ends of the cords into the eyes of the needles, and run the cords through the holes in the shade.
Switch the sides of the cords, and insert them in several holes. Place the upper bar of the shade in its original location, and place the end caps that hold the two bars back. Pull on the cords until the upper shade closes, and insert the cords into the rest of the holes in the shade. Switch the sides of the cords again, and place the bottom bar in its location. Insert the cords in the holes in the end caps, press the end caps back, and pull on the cords to close the shade.