Full Water Rocket Launcher Kit

A perfect project for STEM learning or summer fun!

Everything you need to launch water rockets!

Water rockets are made from soda or seltzer bottles and are powered by compressed air. The Marimo Labs Water Rocket Launcher is small enough to toss in a backpack yet powerful enough to launch a rocket a hundred feet into the air.

All you'll need to get your rocket off the ground is a plastic soda or seltzer bottle, water, and a bike pump that connects to standard Schrader valves found on cars and mountain bike tires.

Make your own for free!

Wait, what now? Yes, we've made the design freely available under a Creative Commons license to advance science and engineering education. 

You can make the printed parts on your 3D printer. Pick up the Core and Non-Printed Parts Subkit here at the Marimo Labs Store to save time and support the project. You can also purchase parts elsewhere. Sample links are on the Printables project page.

Save time and support the project

If you don't have ready access to 3D printers, or are just looking for a ready-to-go solution, you can purchase a kit here. Proceeds go toward improving the design for everyone, as the Marimo Labs Water Rocket Launcher design will remain free forever.

This kit includes all required printed and non-printed parts for the standard design. Printed components are made from American-made PETG polymer for durability and heat resistance. 

Launch videos and design discussions can be found on the Marimo Labs website.

Kit Contents (comes unassembled)

Please see the products image below for included parts. Pictured with 0.5L bottle for scale (not included); compatible with a wide range of soda/seltzer bottles. Colors may vary.

Printed Parts

• 1x Base v1.22
• 1x Collar v1.42
  
• 3x Leg v1.06
• 3x Peg v1.41-L
• 1x Carrier v1.31
  

Clamp and Pin Subkit

• 7x Clamp v1.44
• 1x Launch Pin v1.2 (printed on smooth plate)
• Paraffin beads

Core Subkit

• TR414 tire valve stem
• O-ring 22mm OD x 15mm ID x 3.5mm CS
• 210mm hose extension
• 6" reusable straw (color may vary)
• Core Type B v1.2 (printed)
• Schrader valve tool (color may vary)

Rubber Band and Cord Subkit

• 5x blue EPDM elastic bands #33 (3 1/2" x 1/8")
• 3-meter (10-ft) 1.18mm 100lb tensile strength orange paracord

Printed parts are made in the USA from US filament. Rubber bands and cord are made in the USA. Rubber plumbing parts and straw are made in China.

Instructions

Read all instructions for assembly and safety here.

Safety disclaimers

Note that this launcher design remains an experimental work-in-progress and is not a toy. This kit is made available for convenience and is not warranted for suitability for a particular purpose. Design defects may exist. A responsible supervising adult must make a determination of whether your particular combination of printed and non-printed parts, ground anchoring systems, bottles, hoses, pressurizing systems, personal protective equipment, protocols, users, and environment are safe for your application. 

The launcher must be firmly anchored to the ground for use. Never point at anyone or anything. No one should ever have any body parts above a pressurized bottle, as the bottle may disengage unexpectedly at any time and cause injury. Heat may cause deformation of parts and all parts should be inspected before every use.

Pressurized systems are inherently dangerous. Adult supervision is always required. No warranty or guarantees are made regarding the safety, performance, or completeness of any designs, models, instructions, or analyses presented.