Since swiping a card to make a purchases isn’t quite convenient enough for most people, many credit cards and smartphones have integrated contactless payment functionality. It’s a clever system as long as you’re not paranoid about the security implications. If you were on the fence about this technology, then this DIY NFC payment ring really shows off what the tech is capable of — for better or worse!
The process of making this wearable device is simple in concept, though the execution is fairly involved. First, you’ll need a credit card capable of contactless payments, which can potentially be arranged by a call to your bank. With this in-hand, the card is soaked in acetone to extract the precious payment chip that will be deposited in the magical money ring. In addition to the chip itself, a ~30-inch antenna is required, which creator David Sikes implemented using ultra-thin — .0044” diameter, or 38 AWG — copper wire.
This wire was then soldered to the and wrapped inside of a 3D-printed ring frame that holds everything in place. To finish the ring, a mold was made with another 3D-printed model, allowing the new device to be safely encased in epoxy. As seen in the video below, this well-made ring can now impel the soda machine to dispense drinks for all eternity… though they will still show up on your credit card bill!