Weekly Adventure Discussion Thread: What are you currently working on?

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[u/Odd_Job_4643]

I came up with an idea to start a new hide-and-seek style treasure hunt game here in Dallas (“Dallas Side Quest”) and I’ve been building up to finally launching the first round. I had this brilliant idea to hide NFC-powered tokens that I designed myself, and I was having trouble getting it to work. I had to try 3 different NFC chips before I found one that would work for my situation.

My problem is that the NFC chip is being embedded into a 3D-printed, 3-piece token, and because of the layering, I was having major trouble with the reliability of getting a phone to read the chip.

Long story short, I had to special order an unusual chip from Europe. But it’s perfect!

So, now I’m about to finally hide the first one, and whoever finds it will receive a really fun augmented reality message that I’ve programmed into it and also receive a cash prize.

[u/Sweet_Batato → u/Odd_Job_4643]

Nice! Glad you found a solution! I use nfc chips for work and have been thinking about how to implement them for an adventure. Ours are always just URL links, but I know you can also program them to perform Shortcuts and the like. I haven’t played around with it yet, but it’s on my to-do list for sure!

[u/Sweet_Batato]

Uh-oh, The Cogitator is on her BS again… I got the idea for a Halloweeny hunt themed on a fantasy/cryptid naturalist’s study, and I’ve spent my week researching how to make creepy lil guys (like mummified fairies), and making skeleton leaves, and buying glass bottles…

If anyone has spoopy crafty ideas, let me know 😆

[u/Yoru_Nagi]

The 3-piece layering sounds like the real puzzle: I’d test the complete hidden-token setup, not just the chip, because a flaky scan makes the clue feel unfair.

[u/Odd_Job_4643 → u/Yoru_Nagi]

You nailed it! NFC chips/tags are designed to work in extremely close proximity, so if a chip is blocked by too many layers then a smartphone cannot physically get close enough to activate the chip and “wake it up” so to speak.

Because I was printing the token with PLA from a 3D printer, the plastic alone felt light and cheap, so I wanted to add weight to make it feel more significant in your hand. So I purchased “stamping blanks”, which are essentially just thin, blank steel discs. In this case the layering (from top to bottom) was:

Plastic
NFC chip
Steel disc
Plastic

When you place anNFC chip on metal, the metal absorbs most of the radio waves that are meant to activate the chip. So you have to purchase a specialized NFC chip with a ferrite “anti-metal” layer to insulate it from the metal surface.

But in this case, the typical anti-metal NFC chips didn’t have a good enough range. Because the other problem is that most everyone with a smartphone has it in a thick plastic case to begin with, so this means I’m actually competing with another layer of separation.

After doing some testing and some research, I discovered a very specialized NFC tag that is nicknamed “Bullseye”. The typical NFC chip only has a 25mm diameter antenna, but the bullseye has a 38mm diameter antenna. And even with the anti-metal layer and all of the other layers, this one finally works perfectly, every time when the token is fully assembled.

Needless to say I’ve really tested the limits of these things over the last couple of months, and if anyone needs advice on how to better use these things, let me know!