pxt-calliope/docs/reference/js/lessons/the-watch/activity.md

The watch activity

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BBC micro:bit watch

In this project, you will build your own wearable BBC micro:bit watch from an old pair of jeans and T-shirt. Project duration: 15 minutes.

Materials

• BBC micro:bit, battery holder and 2 AAA batteries
• Old T-shirt
• Old Jeans
• Velcro with sticky back – 5cm x 5cm
• Double-sided tape – 22cm x 5cm. You can find carpet tape in your local hardware shop
• Ruler and pen
• Scissors

Steps

Step 1

Using the ruler and pen, mark a rectangle of more or less 26cm x 5cm on the T-shirt. Don’t worry if you don’t get it quite right, we’ll tidy things up later on.

Step 2

Cut the rectangle using the scissors. Don’t worry about the quality of the cut, we’ll trim it later on.

Step 3

Cut a piece of cloth from the pair of jeans. Cut straight by the seam.

Step 4

Using the ruler and pen, mark a rectangle of 22cm x 5cm (adults should use 24cm x 5cm) on the jeans cloth.

Step 5

Stretch the cloth using your hands and apply the double-side tape on the rectangle marked on the jeans. You might need the help of a friend to achieve this step. Don’t worry if the tape is larger than the rectangle, we will trim it later. Make sure to apply pressure to the tape to secure it firmly.

Step 6

Using the scissors, cut the rectangle of jeans.

Step 7

Peal the tape protective layer from the rectangle.

Step 8

Place the BBC micro:bit pins on the tape at more or less 7 cm from the left border. Then lower the BBC micro:bit on the tape and press gently.

Step 9

Connect the battery holder and place it on the right of the BBC micro:bit. Tuck the cables away on the tape to protect them.

Step 10

Stick the T-shirt rectangle from the top of the BBC micro:bit, over the battery cables.

Step 11

Use your fingers to push the T-shirt cloth under the BBC micro:bit to give access to the micro-USB plug.

Step 12

Place the T-shirt over the battery holder and stick it up to the end.

Step 13

Turn over the watch and cut the extra T-shirt material.

Step 14

Stick the T-shirt cloth on the other side of the watch. Lift the BBC micro:bit pins to slide the cloth under and leave them free from the tape.

Step 15

Turn over the watch and cut left over T-shirt cloth.

Step 16

Cut a 5cm x 5cm square of Velcro loops.

Step 17

Cut a 5cm x 5cm square of Velcro hooks.

Step 18

Stick the Velcro hooks on the right side of the battery holder on the T-shirt cloth.

Step 19

Stick the Velcro loops on the other end on the jeans fabric.

Step 20

Trim any leftover fabric, threads or tape.

Step 21

Your watch is ready!

Acknowledgements

Artistic design by Melinda Hoeneisen.