Step-by-Step :Step-by-Step How to make the motion sensor


Collect all your parts :Collect all your parts acrylic tube 2 paper clips ball bearing 2 acrylic end caps one of them must have 4 (guide) holes in it


Collect your tools :Collect your tools pliers wire cutters wire cutters & wire strippers liquid solvent cement


Pliers :Pliers


Wire Cutters :Wire Cutters only use for cutting wire and solder do NOT use for cutting paper clips as this will damage the wire cutters


Wire Cutters & Wire Strippers :Wire Cutters & Wire Strippers


How to strip wire :How to strip wire grip & squeeze insert wire between jaws wire coating is removed


Liquid Solvent Cement :Liquid Solvent Cement it MUST always be in the wooden block this is so it doesn’t spill you must NEVER take the glass tube out of the block if it is empty, ask the teacher for a refill


Drill holes into end cap :Drill holes into end cap you will need an end cap with 4 guide holes… do NOT use end caps which have 2 or less guide holes …and a “jig” to hold the end cap


Drill holes into end cap :Drill holes into end cap place the end cap (with 4 holes) into the jig… …and swing the metal bar across this will stop the end cap coming out when drilling


Drill holes into end cap :Drill holes into end cap make sure that you have tied back long hair, tucked in ties and removed ID badges you MUST wear goggles hold the jig securely in your LEFT hand – NEVER LET GO WHILST YOU ARE DRILLING use your RIGHT hand to: switch on the power to lower the drill drill the 4 holes raise the drill and then to switch off the power ALWAYS ASK THE TEACHER IF IN DOUBT


Making the tilt switch :Making the tilt switch you will need pliers and paper clips bend out the paper clip… …cut the paper clip… discard this bit you can not cut using the ‘grip’! this will blunt them do NOT use wire cutters …so you have a bit like this


Making the tilt switch :Making the tilt switch now get the end cap with 4 holes… …and force it through… NOT like this one: the holes are too far apart …and it should look like this this should be through the holes which are CLOSEST together the ‘loop’ should be on the inside


Making the tilt switch :Making the tilt switch next, gently open the legs… …and trim off the excess using pliers the paper clip is now fixed in place ~ you should not be able to move it …and bend one leg 90º using pliers…


Making the tilt switch :Making the tilt switch now bend the other leg 90º… …and make another 90º bend… …and one final bend this will be where you will solder a wire


Making the tilt switch :Making the tilt switch cut bend 90º trim force through make loop for wire now repeat the whole process with the other paper clip


Glue end cap onto tube :Glue end cap onto tube …push down firmly for 1 minute use the pipette to put a small amount of glue around the rim of the end cap place tube onto end cap…


Glue end cap onto tube :Glue end cap onto tube place ball bearing inside the tube use the pipette to put a small amount of glue around the rim of the end cap …push down firmly for 1 minute


Get wires :Get wires you will need 2 pieces of wire white yellow blue green these should be no more then 100mm (10cm) long black red do NOT use red or black wire these can be any combination you like – they do NOT have to be the same colour


Strip wire :Strip wire grip & squeeze strip about 20mm (2cm) from one end… …wire coating is removed…


Twist wire :Twist wire …with the wire coating still on – twist the wire… TOP TIP! the wire is made up of many strands – which you will need to twist together …and bend into a ‘V’ shape…


Attach wire :Attach wire …and thread the wire through one of the loops of the motion sensor… …pinch together… …and twist


Solder wire :Solder wire make sure the soldering iron is hot enough… …it should smoke when you touch the solder to it …and put some solder onto the tip this is called ‘tinning’ The soldering iron MUST ALWAYS be in the stand when you are not using it


Solder wire :Solder wire bring the tip of the soldering iron underneath where the metal of the paper clip and wire join… …and bring in the solder from the top. After a few seconds, it should be hot enough for the solder to melt… …and the solder will flow onto the joint, fusing the two metals done


Solder wire :Solder wire now repeat the process with another piece of wire on the other paper clip


Twist wires together :Twist wires together strip the plastic coating from the other ends of the wires… …twist the wires together ~ this will make it look much neater


Testing station :Testing station this is the testing station ~ this is exactly the same circuit you will be making, cased in a wooden box


Test your motion sensor :Test your motion sensor clamp the crocodile clips of the testing station onto your motion sensor… …make sure that it is switched on (toggle switch set to ‘on’) and then tilt your motion sensor… …so that the ball bearing comes into contact with both of the paper clips and trips the alarm ~ you should be able to hear the buzzer and the red LED will come on …tilt the motion sensor so that the ball bearing ‘breaks’ the connection and press the reset button ~ the push-to-make switch repeat a few times to test how well your tilt switch works