How to Make NFC Data Cufflinks to Unlock Your Phone or Store Data
If you want to use NFC in an interesting new way, you can follow Sophy Wong’s guide to create custom contactless cufflinks.
NFC (Near-Field Communication) is a type of RFID (Radio-Frequency Identification) technology that is integrated into most modern smartphones. In some cases you can use your phone’s NFC capabilities to swap contact information with someone by tapping your phone against theirs. But the most common use for NFC on mobile devices today is for sending payments. Apple Pay, Google Pay, and Samsung Pay all work with NFC technology, and make it easy to make a purchase by touching your phone to a reader. If you want to use NFC in an interesting new way, you can follow Sophy Wong’s guide to make custom NFC data cuff links.
This project was originally published in Sophy Wong’s Wearable Tech Projects, which is a publication of HackSpace Magazine. Like all of the other projects in Wearable Tech Projects, this one is an approachable way to use readily-available technology in a fun new way. After making your NFC cuff links, you’ll be able to use them like any other NFC data tag. That means you can use them to store small amounts of data, unlock your smartphone, or trigger just about any other action on an NFC-enabled device. They’ll work very well with any recent Android smartphone that has NFC capabilities, and can be read (but not written) with some iPhone models. You can, of course, also use a dedicated NFC reader/writer, like Adafruit’s PN532 module that works with Arduino boards and Raspberry Pi computers.
To make a pair of cuff links, you’ll need two small NFC tags with the NDEF format. Adafruit sells these in a minuscule 15.6 x 6 mm package. You’ll also need cuff link blanks, clear casting epoxy resin, and silicone cabochon molds. A “cabochon,” if you’re not familiar, is a convex rounded gemstone—as opposed to a gemstone that has been cut with facets. Start by stirring together more resin and dye than you think you’ll need. Don’t shake it! Give it a few minutes to settle, and then use a mixing stick to push the bubbles to a side and pop them. Slowly pour the resin into your molds, and then dip your NFC tags into the resin. After letting them sit for approximately ten minutes, spray some isopropyl alcohol on top to pop the remaining bubbles.
Let the molds sit for the amount of time that the resin manufacturer specifies is necessary for it to fully cure. Once cured, you can remove the resin cabochons from the silicone molds and glue them to your cuff links. E6000 glue should work well, but make sure to use a proper respirator in a well-ventilated area. The final step is to store data on the tags or setup some kind of action to be triggered by them. NFC Tools is a great smartphone app that can handle that, or you can program your own functions if you use a dedicated NFC reader connected to your computer or an Arduino. Now you can wear your data on your sleeves!
