Step 9: Assemble LEDs for upper platform

There are eight large red LEDs on the upper platform that race around in circles when an RFID tag is read.  In this step you will attach the LEDs to their current limiting resistors and long wires that in an upcoming step will be attached to the Arduino and Terminal Strip.  You will need the following parts and tools for this step:
  • 6" 3/32" black heat shrink tubing
  • 6" 1/16" blue heat shrink tubing
  • 8 360 ohm 1/4 watt resistors (Radio Shack part 271-1315)
  • 8 Large red LEDs (T2-1/2 LHR3930 Jameco part 119634)
  • 8 6" lengths of thin black stranded wire (I used #26 AWG)
  • 8 6" lengths of thin blue stranded wire (I used #26 AWG)
  • Wire cutters/strippers
  • Soldering iron and solder
  • Heat gun or other source of directed heat
Follow these instructions for each of the eight LEDs:
  1. For the blue wires:
    1. Strip approximately 1/4" of insulation off one end of each wire.  Using the soldering iron and solder, tin the end of the wire. This will make it easier to insert the wire into the ScrewShield.
    2. Strip 1/2" of insulation off of the other end - do not tin this end.
  2. For the black wires:
    1. Strip 1/2" of insulation off both ends.  Tin one end and leave the other end as is.
    2. Wrap the untinned end of the black wire around the resistor as shown in the first photo.
  3. Solder the black wire to the resistor and the resistor to shorter lead on one of the LEDs.  Cut off excess wire from the resistor. See the second and third photos.
  4. Cut a length of black heat shrink tubing that will cover the exposed wire and resistor.  Slip the tubing onto the wire and cover the exposed areas as shown in the fourth and fifth photos.
  5. Apply heat using a heat gun or other source of heat to the tubing to shrink it around the wire and resistor as shown in the sixth photo.
  6. Wrap the untinned end of the blue wire around the long lead on the LED as shown in the seventh photo.
  7. Solder the wire to the LED as shown in the eighth photo.
  8. Cut a length of blue heat shrink tubing sufficient to cover the exposed wire as shown in the ninth photo.
  9. Slip the heat shrink tubing onto the wire (see tenth photo) and apply heat to shrink the tubing as shown in the eleventh photo.