I was cleaning up when I found an old project of mine: a customized Oyster card. The Oyster card is a RFID or Near Field Communication card, that you can use for traveling in the subway of  London.

To extract the relevant parts, I tossed the card in MEK solvent and watched it fall apart in numerous thin plastic layers, until a small chip emerged, with a coil attached.

Fun-fact: MEK is also known as butanone, A solvent. Evaporates very fast.


Looks like a puppy with a hump. Anyways.

The electronics (tiny) were then sandwiched between some (inlayed!!!) woodfineer layers, and presto: a customized traveling card. I remember being a bit anxious trying it for the first time, but it worked. The bus drivers did not seem to really care when I slammed it against an Oyster-card reader.

The logo on my customized card is from Tintin’s les çigares du pharaon. The thing is expired by now, they are only valid for 2 years or so.