PETG 2L Water Bottle Rocket - Nose Cone and Fins

Water Bottle Rocket – Dual 2L Pepsi Bottles | PETG Build

Made this water bottle rocket using two 2L Pepsi bottles and a few PETG-printed parts. It held up well through multiple launches!

🔧 Key Features:

• Nose cone screws directly onto a standard bottle cap
• Fin holder pressure-fits onto the bottle—no duct tape required if the fit is snug (though I used a bit just for security)
• All printed parts in PETG for durability

🧩 Parts List:

• 2x 2L Pepsi bottles
• 1x 3D printed nose cone
• 1x 3D printed fin holder
• 3x 3D printed fins
• Duct tape (optional)

🛠️ Assembly Steps:

1. Prepare the bottom bottle: Remove the label and cut the bottle evenly to your desired length. I cut mine right where the bottle hits its widest point so it can slide over the main bottle slightly.
2. Join the bottles: Slide the cut bottle over the base of the intact bottle and secure it with tape. This keeps the pressure vessel unmodified, which is often required for safety or competitions.
3. Add components:
   • Screw on the printed nose cone
   • Slide the fin holder onto the lower bottle
   • Insert the 3 fins and secure with tape if needed

✅ Notes:

• PETG parts were strong enough to survive several launches
• Design avoids modifying the pressurized bottle
• No glue or permanent alterations needed