Step 3: The Door and "Thingy"
Part 1: Use some of your longer smooth pieces to make the shaft back to the door. After, make sure you cover you door in smooth pieces, as to make it so it slides back and forth easily. Make sure every thing is stuck together tightly.
Part 2: This is where you need your rubber band, pieces with holes in them and connecter pins. Mount 2 1x2 pieces in a flat 6x2, to brace the pieces with the rubber band. Next mount the 1x2 pieces with holes in them and have the connecter pins in them. You will also have to put the rubber band in the middle of them, but depending on the size of your rubber band, you will need to double or triple fold it. Make sure it cannot come out before continuing. Attach the Pieces that are next to each other to brace them further. After this is done, attach the whole thing together on the top with another 6x2 flat piece. Stretch the rubber band over to your lang connecter pin and connect the connecter pin in the sides of the 2 4x1 pieces with holes in them. Put a 3x2 pice on top to secure it.
After you have completed Parts 1&2, set your main body upside down and put the door in upside down. Attach the "thingy" to the main body, with the smaller part facing in. pull you door all of the way up to the "thingy" and attach the smaller part of the "thingy" to the door. After you do this, test it and make sure there are no kinks.