Nikolai's+and+Wen+Jiang's+Procedure

 Fins: You cut 3 6.7cm long right triangles from the foam board.  Nosecone: You cut out three equilateral triangles and glue them together.  Base: Cut toilet paper roll into 5cm long tube.  Stable Ring: You cut out 2 rings foam board with 5cm diameter and a 2cm hole in the middle.  Putting things together:  - Glue the fins on the side of the base, make sure the fins are spread equal distances apart.  - You insert the stable ring into the middle and bottom of the base, and then insert the body tube through the hole in the middle of the stable ring.  - Insert wood sticks into the base against base, and then cut the body tube in half.  - Glue tin foil on top end of the bottom part of the body tube and tape end of a length of bungee cord on the body tube.  - Tape the other end of bungee cord to the upper part of the other tube.  - Insert the upper part of the body tube carefully in between the wood sticks on to the lower part of the body tube.  - Cut holes on top of the body tube, and insert one end of springs, then seal it with glue.  - Glue the other end of springs and the helicopter rotors together.  - Glue the nosecone on top of the body tube.  - Fold the helicopter rotors at the spaces provided by the base.  - Insert the penholder into the bottom of the lower body tube and only leave 1cm of penny holder outside. <span style="line-height: normal; margin-bottom: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; padding-bottom: 0px; padding-left: 0px; padding-right: 0px; padding-top: 0px;"> - Cut holes on the part of penny holder left outside, unbend a paperclip and poke it through the hole. <span style="line-height: normal; margin-bottom: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; padding-bottom: 0px; padding-left: 0px; padding-right: 0px; padding-top: 0px;"> - Insert the engine into the penny holder and bend the paper clip over the side of the engine.