Introduction: How to Transplant RFID Chips
RFID (radio-frequency identification) systems are all around us. They help us get through toll booths faster. They help stores keep track of inventory. They are even in a lot of toys.
But there is no reason why the RFID chips need to stay in their original housing. In this project, I am going to show you how to transplant a RFID chip into a different housing to make it more convenient or at least more fun use. You can make an RFID reactive wallet, multi-tool, or cell phone case. The only limit is your imagination.
Step 1: Select a RFID Chip to Transplant
The first thing that you need to do is select a RFID chip that you would like to transplant into a different housing. As an example, I am going to be using the chip from a security key fob. This kind of chip is normally used to unlock doors in an office building.
Step 2: Carefully Open the Housing
The best methods for disassembling the housing will vary from model to model. I have a HID ProxKey 1346 Proximity Keyfob. This model has a seam around the middle where the two halves are glued together. So I initially tried to pry it open with a screw driver and then a knife. Unfortunately the seam was too shallow and the plastic was too soft for this to be effective and I only succeeded in scratching up the surface.
The best method that I found for opening this kind of housing is to crack the glue seam by squeezing it. I wrapped the key fob in a napkin to avoid scratching it. Then I squeezed it at one end with a pair of pliers perpendicular to the seam. This caused the two halves to separate slightly at the end. I stuck a screw driver into the opening to hold the two halves apart. Then I repeated this process moving down the side of the key fob until the two halves where mostly separated. At this point I was able to just pull it apart the rest of the way with my fingers.
Alternatively, you can cut the housing open with a knife or rotary tool. If you do this, then you need to be very careful not to cut too deeply or you risk hitting the chip.
Step 3: Carefully Remove the RFID Chip
You need to be extremely careful when removing the chip! I broke the first chip that I was using for this project. So be aware that RFID chips are fragile and it is very easy to accidentally break them. If possible, you should avoid applying any direct pressure to the chip or its sealant.
I decided that the safest way to remove the chip from its housing was to cut it out with a rotary tool. First I cut off the bulk of the attached material. Then I carefully shaved down any remaining chunks of plastic. Remove only as much plastic as you absolutely need to. The more that you cut away, the more you risk damaging the chip.
Step 4: Choose a New Housing for Your RFID Chip
You can use anything as the new housing for your RFID chip. For instance, you could put it in your wallet or inside your cell phone case. However, considering how fragile the chip is, I recommend using a housing that has hard rigid sides such as the inside of a multi-tool. Or you can get creative and put the chip in something unusual.
My favorite housing for an RFID chip is an ordinary stick. That way you can wave it around like a magic wand and it will actually do something like unlock your door. To mount this kind of chip in a wooden dowel or stick, all you have to do is drill a hole in the end that is just big enough to fit the chip.
Step 5: Glue the Chip in Place
Glue both holds the chip in place and helps to protect it. The hardened glue acts as a shell. So feel free to use an excessive amount of glue. Just don't use a glue that greatly shrinks or expands when it cures. If one side changes shape faster than the other, then it can actually bend the chip and break it.
Step 6: Test It to Make Sure That the RFID Chip Still Works
Once you have transplanted your RFID chip and the glue has fully cured, it is time to test it to make sure that it still works. If all went well, it will still function normally and you will be able to use just like a regular key fob.