HackSpace – September 2019

FORGE

Many clones of Arduino Uno boards (available on
eBay) have a line of holes as well as pins, which
makes it easy to solder wires to. If yours only has
header pins, you could remove them or use jumper
wires instead of regular wire.
Connect the red wire beneath the perfboard to
Digital pin 3 on the Uno, the green wire to Digital
pin 5, and the blue wire to Digital pin 6. Make sure
that the components are dry before connecting
to power.

HIDE THE WIRES
Fill a tray with hot water, and sprinkle a layer of
Polymorph granules on top to create a thin sheet.
Remove with a spatula to keep it flat and use a rolling
pin to create a roughly rectangular shape, a little larger
than the gap you hollowed out of the log. Return it to
the water when necessary to keep it flexible.
Hold the Polymorph over the electronics to check
the size, then cut and bend into shape. While it’s
pliable, thin pieces of Polymorph can be cut with
scissors. If you can’t cut it, reheat and roll a bit more.
Use the glue gun or screws to keep it in place.

LET THERE BE LIGHT
Open the Arduino IDE software and connect the
Arduino to your computer. If you are new to Arduino,

check out the guide at hsmag.cc/shYSMW, which

walks you through how to select the board and

port settings.

Install the colour sensor library by going to Sketch

> Include Library > Manage Libraries. Search for

Adafruit TCS34725 and click Install. For help on

installing libraries, go to hsmag.cc/zmXjEI.

Open the ColorView example code that comes

with the sensor library by going to File > Examples >

Adafruit TCS34725 > ColorView.

Upload the code to the Arduino, by going to

Sketch > Upload. Remove the power cord from the

computer and attach it to a USB power supply, either

mains or battery powered. Then hold a colourful

object over the sensor. After a few seconds, the

LEDs should shine the same colour as the object.

Place a different object on the colour sensor and the

LEDs will change colour too.

Left

Colour-coding the

wires makes it easier

if you need to do any

trouble-shooting

Above

Play around with

coloured objects

to explore the

different effects

Left

Perfboard is put

between the log

and the Arduino.

Cover the USB port

with insulating tape

if there is a risk of

components

short-circuiting

Instead of using Polymorph, you could 3D-print

the mushrooms. A search for ‘Mushroom LED’ at

thingiverse.com brings up free designs, ready to resize

and print. Buy diffused RGB LEDs, or cover clear ones

with masking tape or a blob of Polymorph, to make the

colours blend evenly.

PRINT YOUR OWN