Price - Stock No 20



The objective of the Maze is to find a safe path from the IN arrow to the OUT arrow. The safe path is indicated by a GREEN LED, and the RED LED indicates disaster. There is a buffer zone mostly - but not always- between the red and green zones. The buffer zone is indicated by the ORANGE LED. The rule that applies is that you can move forwards or backwards, sideways and diagonally, but only one step at a time. If you wish you could connect a buzzer or construct a sound effects project and connect them into the Orange and the Red circuits.


  1. Set out the grid pattern at 10mm intervals, and mark suitablepositions for the three LEDs and the battery tamer holding screw. You will also need a small hole for the black lead of the battery snap to feed through.
  2. Drill three holes D6.35mm (1/4 inch) and push the LED Mounts into them. Push the LEDs from the under-side into the mounts, but make sure that the SHORT LEGS are all to the grid side. Cut a short piece of wire from the roll in your Kit and lie it along the short legs, soldering the wire to each short leg. Take the 390R resistor and solder one leg to the wire joining the LEDs.
  3. Drill a small hole and feed the black lead of the battery snap through. Solder this lead to the free leg of the resistor. This means that the one resistor will meter the current to all three LEDs, on a common 0 Volt rail (or earth if you like). For a 9 Volt supply, a 390 OHM resistor will allow around 20 milliamps of current to flow through the LEDs. (OHM's Law is used to calculate this). This is the specification for LEDs.
  4. Strip the insulation from each end of the coloured wires and solder one end of each to long leg of the matching colour LED.
  5. Drive flat-head nails through the plywood at each of the points of the grid.
  6. Design your maze and mark the path of the red track.
  7. Using long-nose pliers wrap the end of the wire tightly round the first nail. Lie the wire in and out of successive nails in the path, wrapping it right round every 3rd or 4th nail to keep it tight. Try to ensure that the wire touches each nail. Repeat this process for each of the Orange and Green paths.
  8. Solder the free ends of the coloured wires to their respective path wires.
  9. Solder the alligator clip to the Red wire of the battery snap, and attach the battery tamer with its screw.
  10. Connect a battery and test that a LED lights up when each nail is touched with the alligator clip. For any that don't light push the wire against the nail. For troublesome ones solder the wire to the individual nail.
  11. Test your maze for its safe path.
  12. Cut some coolite for a backing piece and gently tap the nails so the plywood firms down evenly onto the coolite.
  13. Mark the ENTRY and EXIT and your maze is ready.

Tread lightly

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