QR Code Game Rules

I know there are already a bunch of QR code generators out there on MakerWorld, but none of them solved my very specific problem, so I built my own.

The story behind it

I'm a big fan of printing rugged travel cases for my card games like Flip 7, Skyjo, UNO and the rest. They make it so much easier to throw a deck in your bag and take it on holiday or to the park instead of lugging the whole bulky box around.

But there's always the same issue: I leave the box at home, and with it the rulebook. And of course, the one moment someone asks "wait, what was the rule for...?", nobody remembers.

So I came up with this: print a single small card that lives with the deck. On it: a QR code linking directly to the rules PDF. Pull out your phone, scan, done. The big box stays home, the rules come with you.

Yes, very niche, I know. But maybe a few of you out there have the exact same problem and this solves it for you too.

Features

- Fully parametric, works with any common card size (Poker, Bridge, Skat, Euro/UNO/Skyjo, Yu-Gi-Oh, Tarot, square Dobble, Mini, or fully custom)
- Paste any URL: your rules PDF, BoardGameGeek page, YouTube tutorial, whatever fits
- Optional label text for the game name
- Classic playing card suit decorations in the corners (♠ ♥ ♦ ♣ or all four)
- Each element is a separate object, so you can assign different filament colours in Bambu Studio for clean two-tone prints
- 100% self-contained `.scad` file, no library imports, no dependencies
- MakerWorld Customizer compatible, change everything from your browser

Print tips

- Slice with a filament change at card thickness for a white card body with dark QR and suits
- 0.4 mm nozzle works fine, just keep the QR margin generous so modules stay readable

**Troubleshooting**

If your print comes out messy or hard to scan, two tips that solved it for me:

1. Set the QR height to 1 mm. Lower values can cause issues with module separation on FDM printers, 1 mm gives you reliable, clean modules every time.
2. If your URL is long, run it through tinyurl.com or bit.ly first. A shorter URL means fewer modules in the QR code, which means each module gets bigger and prints much more cleanly. This makes a huge difference if your link points to something like a Google Drive PDF with a long path.

Update

Added a universal rules card to the project that works for any game. Print one and keep it handy for the friends who ask about the rules every five minutes mid-game. Teach them the proper way with a classic Rickroll.

If you create your own cards for specific games, feel free to upload them and add them as print profiles to this model. Would be great to see a little collection grow over time.

Credits

- QR code algorithm based on [scadqr](https://github.com/xypwn/scadqr) by xypwn (MIT License). Huge thanks for making the math available.
- Special thanks to [QR Code Generator (qrcode for mail, wifi, etc)](https://makerworld.com/de/models/476280) for inspiring this project. Their model handles the general-purpose case beautifully, mine is the playing-card-specific cousin.

Friendly reminder:

If you’re interested in more of my 3D models, here are other designs you might like as well:

Shoji Art Lamp

Two of the included window designs were newly created specifically for this dice tower, Geisha and Koi. They are also compatible with my Shoji lamp.
If you're interested, you can find the lamp here (click image):

Maximum Display Shelf
Show more, store more, maximize your space while keeping your models beautifully displayed.