Project:Hacking RFID for jewellery

From London Hackspace Wiki
RFID Jewellery
Created 27/03/2012
Members Akki14
QR code


Description

(Warning, work in progress, may not actually work yet)

It's awkward looking for a card in a bag and nearly impossible to find high-frequency RFID implants so I've decided to try to make an RFID ring to wear on my left hand to open the Hackspace door quickly and easily.

Fob with cover popped off

Components

  • RFID keyfob
  • Sally Hansen Acetone Free Nail Polish Remover
  • a vice
  • Sugru
  • wire
  • (optional) 3mm blinking LEDs + batteries

Process

Open RFID keyfob with the vice... Carefully insert it so it's horizontal and only gently press with the vice until the cap comes flying off. Possibly wear eye protection and warn others around you that you're going to do this. This method seemed better than trying to stab at the fob with metal objects or dissolving in acetone (Thanks to Hipster for the vice suggestion).

Use the nail polish remover to dissolve the glue holding the RFID tag into the fob.

RFID removed from fob

Make a new, smaller spiral antenna out of very thin wire. You'll need 20-21cm of wire. Solder onto RFID chip on the two tags either side of the chip.


Update: Find out that all of the above is very difficult actually. Purchase 13mm x 2mm round RFID tags for further experimentation. Didn't work - too small of an antenna for the door reader to recognise.

Now have a bracelet arrangement made out of breadboard wire with one of the keyfobs instead.

RFIDWireBracelet.jpg

Possibly going to form a case around the fob in fimo, separate into two halves, bake, then put back together with sugru to make it prettier. The bracelet seems to work pretty well but I'll have to trial it a bit more to make sure. Turning this into a ring would be rather large and chunky, unfortunately...