How to Generate, Design, and 3D Print QR Codes

QR codes are a fantastic way to share info—like URLs, Wi-Fi details, or contacts—in a scannable format. With 3D printing, you can turn them into durable, physical objects. In this tutorial, I’ll show you how to generate QR codes, edit SVG files, design a sign using easy software, and 3D print them, sticking to SVG files (not PNGs) for the best results in 3D modeling. Let’s get started!

Step 1: Generate Your QR Code as an SVG

To create a 3D-printable QR code, you need a vector file (SVG), not a raster image (PNG), because SVGs maintain crisp edges and work seamlessly with 3D design tools. Here are some free websites to generate QR codes in SVG format:

● QR TIGER (https://www.qrcode-tiger.com/)
 Offers dynamic QR codes and customization. Input your info, design it, and download in SVG format.

● Adobe Express QR Code Maker (https://www.adobe.com/express/feature/image/qr-code-generator)
 Simple and free. Create your QR code and download it as an SVG.

How to Do It:

1. Visit one of these sites.

2. Enter the info you want linked (e.g., a URL, text, or Wi-Fi details).

3. Customize if desired (colors, logos, etc.).

4. Download the QR code as an SVG file—avoid PNGs, as they’re not ideal for 3D modeling.

Step 2: Design a Sign with Your QR Code Using Easy Software

 Tinkercad

Tinkercad is a free, web-based 3D design tool that’s perfect for creating your sign and preparing it for printing—all while using your SVG file directly.

● Where to Find It: tinkercad.com

● How to Use It:

1. Sign up or log in to Tinkercad.

2. Click “Create” > “3D Design” to start a new project.

3. Import your QR code (after editing in Step 3):

■ Go to the top-right corner, click “Import,” and upload your edited SVG file.

■ Adjust the size (e.g., 60mm x 60mm) and height (e.g., 2mm) for the raised QR code.

4. Create a base for your sign:

■ Drag a “Box” shape from the right-hand menu onto the workplane.

■ Resize it slightly larger than your QR code (e.g., 70mm x 70mm x 1mm) as a backdrop.

■ Select Import Shapes select your SVG file

■ Align the QR code on top (use the “Align” tool under “Adjust”).

5. Add text (optional):

■ Drag the “Text” shape, type your message (e.g., “Scan Here”), and adjust its size/position.

6. Group everything (select all, click “Group” at the top) to combine into one object.

● Why SVG Matters: Tinkercad imports SVGs cleanly, turning them into 3D extrusions. PNGs, being raster images, don’t work as well and can result in jagged edges.

Step 3: Edit Your SVG to Remove White Background Paths

Some QR code generators include a white background as part of the SVG file, which can mess up your 3D model by adding an unwanted flat plane. Here’s how to edit your SVG to remove it:

Why Edit?

● In 3D printing, you only want the QR code’s black pattern (the raised part) without a white background path, as the base will be added separately in Tinkercad.

Tools to Use:

● Inkscape (inkscape.org) - Free, open-source vector editor.

● Adobe Illustrator - If you have access (not free).

● Online Editors - Like vectr.com or photopea.com (free, web-based).

How to Do It (Using Inkscape):

1. Download and Install Inkscape (if not already installed).

2. Open Your SVG:

○ Launch Inkscape, go to “File” > “Open,” and select your QR code SVG.

3. Ungroup Elements:

○ Select the QR code (click it), then go to “Object” > “Ungroup” (or Shift+Ctrl+G). This separates the paths.

4. Identify the Background:

○ Click around to find the white rectangle or square (it might be a filled path or a separate layer). It’s usually larger than the QR code pattern.

○ If it’s not obvious, use the “Node Tool” (F2) to inspect paths—look for a solid shape behind the QR code.

5. Delete the Background:

○ Select the white background path and press “Delete.” You should be left with just the black QR code pattern (and any custom elements like logos).

6. Save Your Edited SVG:

○ Go to “File” > “Save As,” choose “Plain SVG” (not “Inkscape SVG”), and save it.

Step 4: Clean Your SVG to Remove Random Vector Artifacts

A clean SVG file is crucial for Tinkercad (and PrusaSlicer) to work properly. Random vector paths or artifacts—like stray lines, overlapping shapes, or hidden elements—can create unwanted 3D geometry or cause import errors. Here’s how to tidy it up:

Why Clean It?

● Artifacts can turn into odd protrusions or holes in your 3D model, making it unprintable or unscannable.

How to Do It (Using Inkscape):

1. Open Your SVG from Step 3:

○ If you haven’t already, load it in Inkscape.

2. Ungroup Again (If Needed):

○ Select all (Ctrl+A) and ungroup (Shift+Ctrl+G) multiple times until no groups remain.

3. Check for Artifacts:

○ Look for stray lines, tiny shapes, or overlapping paths outside the main QR code pattern (e.g., from logos or design extras).

4. Delete Unwanted Paths:

○ Select each artifact with the “Select Tool”  and press “Delete.” Keep only the QR code’s functional black pattern.

○ If unsure, test-scan the QR code after each deletion to ensure it still works.

5. Simplify (Optional):

○ Select the QR code, go to “Path” > “Simplify” (Ctrl+L), and reduce slightly to smooth minor irregularities—but don’t overdo it, or you’ll lose detail.

6. Save Your Clean SVG:

○ “File” > “Save As” > “Plain SVG.”

Step 5: 3D Print Your QR Code Sign

How to Print:

1. Import Your STL File:

○ Open your slicer (e.g., Cura) and load the STL from Tinkercad.

2. Adjust Settings:

○ Layer Height: 0.2mm for detail.

○ Infill: 20-100% (100% for a solid sign).

○ Nozzle Size: 0.4mm is fine.

○ Size: Make your QR code at least 50mm x 50mm for scannability (more in Step 7).

3. Set Up Dual Colors (Optional):

○ Single-extruder: Print the base in white, pause at the QR code layer (“Pause at Height” in Cura), and switch to black filament.

○ Dual-extruder: Assign white to the base and black to the QR code in your slicer.

4. Slice and Print:

○ Generate the G-code and send it to your printer.

○ Print at 40-50mm/s for precision.

5. Test It:

○ Scan the printed QR code with your phone. If it doesn’t work, adjust size or contrast (e.g., paint the raised parts black).

Step 6: 2-Color 3D Printing for QR Codes

Source: 3D printed QR codes

● Single-Extruder Printers:

○ Use one nozzle and manually swap filament mid-print.

○ In your slicer (e.g., Cura), add a “Pause at Height” at the layer where the base ends and the QR code begins (e.g., 1mm height if your base is 1mm thick).

○ When the printer pauses, swap the filament (white to black) and resume printing.

○ Pro Tip: Practice with a small test print to nail the timing.

● Dual-Extruder Printers:

○ Use two nozzles for automatic color switching.

○ In Tinkercad, export the base and QR code as separate STL files (don’t group them).

○ In your slicer, assign one extruder to the base (white) and the other to the QR code (black), then align them.

○ Pro Tip: Calibrate your printer to avoid oozing or misalignment.

Step 7: Make Your QR Code Large Enough for Scanning

Size matters when 3D printing QR codes—too small, and phones won’t scan them reliably. Here’s how to ensure your print is big enough:

● Minimum Size:

○ Aim for at least 80mm x 80mm for the QR code itself (not including the base). This ensures the “modules” (the little squares) are large enough for most phone cameras to detect.

○ For complex QR codes (e.g., long URLs), go bigger—100mm x 100mm or more.

● Module Size:

○ Each module should be at least 1mm x 1mm in size. A 50mm QR code with 25 modules per side meets this threshold, but smaller than that risks failure.

● In Tinkercad:

○ When importing your SVG, set the width and length to at least 50mm (adjust in the top toolbar after import). Scale proportionally to avoid distortion.

○ Add a base that’s 5-10mm larger on each side (e.g., 60mm x 60mm) for stability and aesthetics.

● In Your Slicer:

○ Double-check the size after importing the STL. Use the “Scale” tool (e.g., in Cura) to increase if needed—don’t go below 50mm unless testing a very simple QR code (e.g., short text).

○ Test a small sample first if unsure, but avoid tiny prints (under 30mm) as they rarely scan.

● Why Not Too Small?

○ Small QR codes lose detail in 3D printing due to nozzle limitations (e.g., 0.4mm nozzle can’t resolve tiny features), and cameras struggle to pick up the pattern.