Attaching Fins to a Bottle Rocket

• 1). Wrap the tape measure around the bottle and measure its circumference. This is the point where the tape measure starts to overlap on itself. Write down this measurement.
  
  
• 2). Divide the circumference by 3 if you are using three fins or by 4 if you are using four fins. This will give you the distance there needs to be between each fin to ensure they are set evenly apart on the bottle.
  
  
• 3). Wrap the tape measure round the bottle again and use its measure guide and the pen to mark out the 3 or 4 spots an equal distance apart where the fins will go.
  
  
• 4). Place the ruler against the bottle at each of the points you have marked and use the pen to draw a straight line to the base of the bottle rocket. Decide how far up the bottle rocket you wish the fins to sit and use the pen to mark the same height on each of the lines.
  
  
• 5). Run the glue gun down one line, starting at the highest point you have marked, ensuring an even spread of glue. Press the edge of one fin into it and hold it in place until it starts to stick. Tape can be used to hold it in place during this process. After the glue has fully dried, repeat this process with the next fin on the next line until all of the fins have been attached.