Step #1: Assemble the submarine interior.Next
- To see the original Howtoons cartoon full-size, click on the "View huge" link at the top left of this image (mouse over it and you'll see the link).
- Drill a hole in the bottom of your bottle.
- Using chopsticks, feed a paper clip through.
- Hook paper clip into second hole for stability.
- Use chopsticks to hook the rubber band to the paper clip.
Step #2: Next
- Connect ruler stabilizer fins with 2 rubber bands.
- NOTE: Why you need stabilizer fins: Without fins, prop and bottle both spin in opposite directions. With stabilizing fins, the prop spins and the bottle moves forward.
Step #3: Make the propeller.Next
- Crush, then cut a bottle in half.
- Trim around the bottom, and cut through the middle of each high and low point.
- Drill a hole in the bottle cap.
- Straighten paper clip, and feed through bottle cap then through propeller's center hole. Bend a hook into second hole.
- Attach loose end of rubber band to paper clip hook.
Step #4: Experiment with buoyancy.
- With lots of air inside, the sub has positive buoyancy and will rise under water or float on top.
- With just enough air inside, the sub has neutral buoyancy and will stay level under water.
- With little or no air inside, the sub has negative buoyancy and will sink under water.