Print the perfect 3D QR Code

Dimensions

Ensuring the correct dimensions for the 3D model is essential to print a perfect 3D QR Code. Printing it too small or too large can result in difficulty or even failure to scan. The QR Code consists of individual squares. As the text inside the QR Code increases or when a frame is added, the squares shrink, making the code more challenging to read.

QR Code size

Through our investigation, we've discovered that for the QR Code to function perfectly, each square should be at least 2.5mm in size. The different sizes for QR Codes are: 21x21, 25x25, 29x29, 33x33, 37x37, 41x41 until 177x177. The base takes 8 squares total (4 on each size). Therefore, the recommended image size for each QR Code version are:

• 21x21: 72.5mm (29 squares * 2.5mm)
• 25x25: 82.5mm (33 squares * 2.5mm)
• 29x29: 92.5mm (37 squares * 2.5mm)
• 33x33: 102.5mm (41 squares * 2.5mm)
• 37x37: 112.5mm (45 squares * 2.5mm)
• 41x41: 122.5mm (49 squares * 2.5mm)
• 177x177: 462.5mm (185 squares * 2.5mm)

These numbers assume that no frame has been used, as this wil alter the size of squares.

QR Code height

How high you make the QR Code above the base matters a lot. If it's too high, it can mess up how well the QR Code can be scanned, especially if it's too high. If it's too high, it can cover part of the base in a way that creates shadows and makes it tough for a QR Code Scanner.

To avoid these issues, it's best to keep the QR Code height at 0.5mm. This size makes sure the QR Code can be scanned easily from any angle.

The height of the base doesn't affect how well the QR Code can be scanned. If you set it to 1.5mm, it gives the QR Code a sturdy feel. However, keep in mind that magnets can impact the height. So, if you're thinking of adding magnets, make sure to read that part first.

Color

QR Codes work the best when there is as much contrast between the colors. So we recommend to stay with black and white colors. Try to avoid filaments with the properies of glossy/shiny/reflecting/glowing, as these can cause trouble with scanning.

Add a color change at the top of the base, so that you can remove the white filament, and add the black filament.

Magnets

Magnets offer a convenient way to place the QR Code on magnetic surfaces like fridges, making it easy to share information, such as your Wi-Fi details, with guests. Optimal magnets for this purpose are Neodymium magnets, known for their strong magnetic properties. Neodymium magnets come with different ratings, ranging from N35 to N55, with N55 being the strongest. In our testing, we found that N35 magnets, which are round and used in sets of four, effectively support the QR Code.

When determining the base height, we consider the magnet's height and add 0.5mm to ensure the magnet remains hidden behind the QR Code and doesn't add excessive weight. For example:

• Round magnet 15x1mm: Base height of 1.5mm
• Round magnet 10x1.5mm: Base height of 2mm

Considering filament properties, it's crucial to adjust the hole size for the magnets due to filament shrinkage during cooling. For 15x1mm magnets, we recommend a width of 15.3mm and a height of 1.15mm; for 10x1.5mm magnets, a width of 10.3mm and a height of 1.65mm.

To fit the magnets, wait until the printing is complete, then use a drop of super glue (cyanoacrylate) and press the magnet firmly into place. Be sure to wear gloves to avoid glue on your hands.

embed magnets

While it's possible to embed magnets inside the base, we don't recommend it due to the following reasons:

• It requires a thicker base to hide the magnet.
• The magnet needs to be stronger as the distance between the magnet and the metal surface increases.
• Neodymium loses its magnetic properties at temperatures above 80 °C/176 °F, and the print head operates at higher temperatures.
• Without adding slack, the magnet may protrude and potentially collide with the print head.

File format

The two primary file formats used for 3D printing are .stl and .3mf. The advantage of using .3mf is that it already incorporates color information. Certain slicers have the capability to seamlessly integrate filament changes automatically when working with .3mf files, streamlining the 3D printing workflow.

Other settings

• layer height: 0.15mm
• Ironing: After testing, we observed that enabling ironing led to increased issues with stringing and negatively impacted readability. Therefore, we do not recommend using this setting.
• Infill: It's advised to use the default settings for infill, as it has no significant impact given the relatively flat nature of the print.
• Color Change: Implement a color change between the base and the first layer of the QR Code.

Advanced

Take into account the varied accuracy of different 3D printers. High-quality FDM printers can achieve sizes as small as 1.35mm per square, allowing for a 50mm print size for a 29x29 QR Code. Note that at these smaller sizes, stringing may become more noticeable, but a heat gun can help mitigate this issue.

For even finer details, consider using a resin printer. While color changes aren't directly possible, you can manually add color using black paint or a black marker after the print has finished.

Example

If you have magnets sized 15x1mm and intend to 3D print a WiFi QR Code, the recommended settings would likely be:

• Format: STL/3MF
• With base
• Image size: 102.5
• QR Code height: 0.5
• Base height 1.5
• Round magnet holes
• Magnet Count: 4
• magnet diameter: 15.3
• Magnet depth: 1.15

Conclusion

when 3D printing QR Codes, it's important to strike a balance. Avoid printing too small or too high, and remember to add a bit of slack for the magnet holes. By following these general guidelines, you can ensure that your print turns out perfect. If you wish to create your own 3D QR Code, you can easily create them at Free 3D QR Code Generator