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Print the NASA Ratcheting Wrench from Space

By Mike · Published January 30, 2026

The First Tool "Emailed" to Space!

In 2014, NASA made history by transmitting a 3D model file from Earth to the International Space Station, where astronauts printed a ratcheting socket wrench. This wasn't just a cool experiment - it proved that future space missions can manufacture tools on-demand instead of carrying every possible tool from Earth. And the best part? NASA released the file for free, so YOU can print the same wrench!

Difficulty Level

Beginner - If you can operate a 3D printer, you can make this

Time Required

3-5 hours print time, minimal post-processing

Why This Project Matters

  • Historical significance: First object ever 3D printed in space
  • Proof of concept: On-demand manufacturing for space exploration
  • Open source: NASA released the files for everyone to use
  • Functional tool: It actually works as a real wrench!
  • Great conversation starter: "I printed the same wrench they use in space!"

Materials Needed

  • PLA or PETG filament - about 50-70 grams
  • ABS filament (optional) - if you want to match what NASA used
  • 3D printer with at least 150mm build volume
  • Slicing software (Cura, PrusaSlicer, etc.)

Filament Choice

PLA: Easiest to print, good for display pieces
PETG: Stronger and more durable, better for actual use
ABS: What NASA used in space, but harder to print (requires heated enclosure)

Download the Official NASA File

NASA released this file to the public domain. You can download it free from:

  • NASA's official site: nasa.gov/3d-resources/
  • Thingiverse: Search "NASA wrench" or "ISS wrench"
  • NASA's 3D Resources page: Direct STL download

File name: Usually called "Ratcheting Socket Wrench" or "ISS Wrench"

License: Public domain - NASA work is not copyrighted!

Printer Settings for Best Results

Basic Settings

  • Layer height: 0.2mm (balance of speed and quality)
  • Infill: 30-50% (higher for a tool you'll use, lower for display)
  • Infill pattern: Gyroid or grid (strong in all directions)
  • Perimeters: 3-4 walls (makes the wrench much stronger)
  • Top/bottom layers: 5-6 layers
  • Print speed: 50-60mm/s (slower = better quality for moving parts)

Advanced Settings

  • Supports: YES - the ratcheting mechanism needs support
  • Support type: Tree supports or "Support on build plate only"
  • Support density: 15-20%
  • Brim: Optional - helps with bed adhesion
  • Cooling: 100% fan for PLA, 50% for PETG

Critical Settings for Functionality

The ratchet mechanism has tight tolerances! If your printer isn't well-calibrated, the ratchet might not work.

  • Horizontal expansion: Try -0.05mm to -0.1mm compensation (makes holes slightly bigger)
  • First layer height: Must be perfect for moving parts to work
  • Bed leveling: Critical - level your bed carefully!

Step-by-Step Printing Process

Step 1: Import STL into Your Slicer

Open your slicing software (Cura, PrusaSlicer, etc.) and import the NASA wrench STL file. The slicer will show you the 3D model on your virtual build plate.

Step 2: Orient the Model

The wrench should print flat on the build plate with the ratchet mechanism facing up. This is usually the default orientation. Don't try to print it standing up - it will fail!

Step 3: Add Supports

Enable supports in your slicer. The ratcheting pawls (the little teeth inside) need support, or they'll print in mid-air and fail. Most slicers auto-generate supports in the right places.

Step 4: Slice and Preview

Click "Slice" and review the layer preview. Scrub through the layers and check:

  • Supports are present inside the ratchet housing
  • The first layer looks complete with no gaps
  • Estimated print time (should be 3-5 hours)
  • Filament usage (50-70 grams)

Step 5: Print!

Send the file to your printer and start the print. Watch the first layer carefully - if it doesn't stick perfectly, stop and re-level your bed.

Pro tip: The first 20 minutes are critical. If the first few layers look good, you can safely walk away.

Step 6: Monitor the Support Areas

When the printer reaches the ratchet mechanism (usually around 50-70% through), watch to make sure supports are printing correctly. This is where most failures happen.

Post-Processing

Step 1: Remove from Build Plate

Let the print cool completely before removing. Use a spatula or scraper to gently pry it off. If using PLA on glass, it should pop off easily when cool.

Step 2: Remove Supports

Carefully remove all support material from inside the ratchet housing. Use needle-nose pliers or flush cutters. Be gentle - don't break the pawls (the little teeth)!

Stubborn supports? Soak in warm water for 10 minutes (for PLA) to soften them slightly.

Step 3: Clean Up the Mechanism

Use a hobby knife or small file to clean up any strings or rough spots inside the ratchet. The pawls need to move freely.

Step 4: Test the Ratchet

Twist the wrench handle back and forth. You should hear/feel it ratchet - clicking in one direction and freewheeling in the other. If it doesn't work:

  • Remove more support material
  • File down any rough spots
  • Check if the pawls are broken (look closely with a flashlight)

Step 5: Optional - Lubricate

Add a tiny drop of 3-in-1 oil or sewing machine oil to the ratchet mechanism. This makes it click smoother. Wipe off excess oil.

Using Your NASA Wrench

What Size Socket?

The NASA wrench is designed for 1/4" drive sockets (the small ones). You can buy socket sets at any hardware store. Common sizes:

  • 7mm, 8mm, 10mm metric sockets
  • 1/4", 5/16", 3/8" imperial sockets

Strength and Limitations

What it CAN do:

  • Light assembly work (furniture, electronics)
  • Tightening small bolts and nuts
  • Educational demonstrations
  • Proof that 3D-printed tools work!

What it CAN'T do:

  • Heavy torque applications (engine work, lug nuts)
  • High-heat environments (PLA melts at 60°C / 140°F)
  • Replace metal tools for professional use

In space, NASA's version was used for: Light maintenance tasks, experiment assembly, and proof-of-concept testing.

The History Behind This Tool

December 2014: A Space First

When Commander Barry Wilmore aboard the ISS needed a specific wrench, NASA engineers on Earth designed it, emailed the file upward, and the ISS's 3D printer manufactured it - all in less than a week. Traditional resupply missions take months and cost millions.

Why This Matters for Space Exploration

  • Mars missions: No resupply possible - astronauts must make their own tools
  • Emergency repairs: Can't wait 6 months for the next cargo ship
  • Weight savings: Carry raw filament instead of thousands of pre-made tools
  • Custom solutions: Design and print tools for unexpected problems

Troubleshooting Common Print Issues

Ratchet doesn't click: Pawls stuck or broken. Remove supports more carefully, or try printing with finer layer height (0.15mm).

Layers are separating: Temperature too low or cooling too high. Increase nozzle temp by 5°C and reduce fan speed.

Supports won't come out: Printed too hot or support density too high. Use tree supports or reduce support density to 10-15%.

First layer didn't stick: Bed not level or nozzle too far from bed. Re-level and adjust Z-offset.

Print warped off bed: Enclosure or brim needed. Use a brim, or for ABS, print in an enclosure.

Design Variations and Remixes

The 3D printing community has created variations:

  • Stronger ratchet design: Thicker pawls
  • 3/8" drive version: For larger sockets
  • Multi-tool version: Adds screwdriver bits
  • Compact version: Smaller for tight spaces

Search Thingiverse or Printables for "NASA wrench remix" to find these.

Educational Value

This project is perfect for teaching:

  • STEM concepts: Manufacturing, space exploration, engineering
  • Problem-solving: Why would astronauts need 3D printing?
  • Design thinking: How do you design a tool that works in microgravity?
  • Technology: How 3D printing works

Share Your Print!

NASA loves seeing people use their designs. Share your finished wrench:

  • Tag @NASA on social media
  • Use hashtag #3DPrintinSpace
  • Upload a "Make" on Thingiverse or Printables

Other NASA 3D Printable Models

NASA has released hundreds of free 3D models including:

  • Spacecraft and satellites
  • Topographical maps of Mars and the Moon
  • Asteroids and planets
  • Space station modules
  • Tools and experiments

Browse the full collection at nasa.gov/3d-resources/

Official Source and License

Original file source: NASA's 3D Resources database
License: Public domain - NASA content is not copyrighted
Designer: NASA Marshall Space Flight Center
First printed in space: December 20, 2014 aboard ISS
Made In Space partner: Printed on the ISS's "Made In Space" 3D printer

This project uses official NASA 3D model files which are in the public domain. NASA's work is freely available for public use. For more information, visit NASA's 3D Resources.

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