Quoted from Heater:
Word of caution. I put the SD card back into the fan and accidentally put it in at an angle and it fell straight inside the fan arms. I can hear it rattling around but it stops when the fan is at full speed. There is no apparent easy way to take it apart. Be sure when you put it back it in,do so carefully.
That happened to me as well. It's actually pretty simple to get out. The blades snap apart easily. Then I had to remove a few screws to lift off the round plastic so I could get the card out. It shouldn't take you more than a few minutes to retrieve it.