This is a tutorial for building a marble cannon.
Created by: Erin Hawkins and Evan Morris
Step 1: Gather Materials and Equipment.
- 3/4 in. PVC Pipe
- Two Zip Ties
- Hot Glue
- Wood glue
- 3 in. Spring
- Metal Sheet
- 16x16 in. Plywood Square
- 2 3x4 in. Wood Blocks
- Metal Hinge
- 3/4 in. PVC Cap
- 3 Screws
- Hot glue gun
- Power saw
- Power drill
Step 2: Attach 3x4 In. Wood Blocks Together With Wood Glue
Let sit overnight with clamps so that the blocks do not move.
Step 3: Attach Connected Wood Blocks to the 16x16 In. Wood Base.
Use wood glue and attach at the center of the base.
Step 4: Drill Hinge Onto Wood Blocks Using Screws.
Step 5: Cut Slits Into PVC Pipe.
Cut a slit at 2.5 in and 1.6 in from the bottom side of the pipe.
Step 6: Affix PVC Pipe to Hinge Using Hot Glue and Zip Ties.
Wait for the hot glue to dry. Use hot glue to fill in the gaps between the zip ties and PVC pipe.
Pro tip: Put hot glue on the underside of the hinge for added stability.
Step 7: Affix Protractor to the Side of the Cannon.
Use hot glue to place the protractor on either the left side or the right side of the cannon with the middle of the bottom of the protractor lined up with the "hinge" part of the hinge.
Step 8: Create a Hot Glue Circle.
On wax paper, use the hot glue gun to make a circular shape of glue. Cut it so that it fits on the top of the spring(.05 in. in diameter)
Step 9: Affix Glue Circle to Spring.
Using more hot glue, place the circle on either end of the spring.
This will keep the marble from falling through the spring when the cannon is launched.
Step 10: Test the Cannon at Various Angles and at Different Slits Until Standard Distance Values Are Obtained
To fire the cannon, follow these steps:
- Place the metal sheet through either slit
- Place the marble into the cannon barrel(PVC pipe)
- Push the spring into the cannon with the hot glue circle facing the marble
- Use the PVC cap to compress the spring by pushing it onto the end of the PVC
- Pull the metal sheet out so that the spring shoots the marble forward
Step 11: Hope You Get an "A" on Your Project.
Step 12: Calculations
Trials___Launch Height(m)__Angle__Distance(m)___Time(s)__Initial Velocity(m/s)__
These calculations show the time it took for the marble to land and the initial speed the cannon fired at. The calculations also show that the cannon is mostly consistent. However, the similarity in launch height and angle, but the difference in distance, time, and velocity for trials 2 and 3 show that there was possibly an error when firing the cannon. For example, the PVC cap not being tightly put on, decreasing the compression of the spring.