Flux Capacitor -VERY EASY TO BUILD

Introduction: Flux Capacitor -VERY EASY TO BUILD

make a Back To The Future  *Flux Capacitor* but dont want to spend 300$ or spend any money? well i know you want to read this so.
i made a BTTF Flux Capacitor for free, by using an old pc as my *parts*
its wired up that it runs off the 12V car battery in my golf.

total cost >> FREE! 

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Step 1: Parts

1 or 2 old pcs,
solder iron,
3 old spark plugs
plastic pipe
black rattle can

if you are like me you will have a least one old pc around the place, with windows 3.1 or 95 or something like that or have come a cross a old unwated pc and you get it for free  :D

well thats just me...

fun part
taking the old pc apart
stripping the old pc down you will notice there is  leds on:

>>the cd rom drive,
>>floppy drive,
>> front light for hard drive in use
>> sometimes a reboot led beside the reboot button
and the Start/Power button

now as it turns out each of them can have different colours,
ie, hard disk can be orange,
flop disk can be green or orange,/yellow
cd rom is usually green,
hard disk and restart can be red or orange...

so usually there will be Green Red Orange/ yellow
you will need 4 LEDS

reason for 4 leds is  you are running a 12V batter power supply, and the pc operates at  0-5Vs
but that does not mean the LEDs are 5v leds, if they are only coming on for a second, they can be 3v leds

so for safety to prevent them from burning out we are going with 4, plus,  more leds = more light

just to note, more leds = more lights but more leds means the leds are not as bright but this is good as you dont want extremely bright leds in the back of your car

for this step you should have 4 leds its best if they are all the same colour or near enough. to being the same colour  (ie orange and red is ok)

what i did was got 2 old pcs and got 4 Green LEDS

Step 2: Testing Leds

i got a AC mains transformer  (AC>>DC) with a range of 3, 5, 7, 9,12, 14 V

using the transformer at 5v  i was able to test that each of the leds worked, and i has a number of leds so could see which gave off the most light (some leds were very big and some were very small in size)
and some gave off more light that others

Step 3: Layout

getting some plastic pipe i cut it down to size, and filed the ends of the top part of the Y so they matched together and popped in one of the smaller green LEDS, then added the final piped that pointed down. and taped them all together

the led in the middle pointed upwards, so it lights the 2 upper Y pipes. while at the end of the Y pipes there is a single led pointing back in to the center of the Y

on a scrap piece of wood, i drilled some holes and laid out the basic shape

the wires for the leds are hidded by drilling small holes to run the wire through..

spark plugs out of a old car were used to hide the wire more.and to give a more BTTF Flux capacitor look.

the length of each pipe i got from another person here on instructables.com,  sorry dont know your name
 but i didnt use 9 leds like he did,

the main difference is that my flux capacitor does not flash, its just ON or OFF.

Step 4: Construction

gut the pc box, place wood on the sides to cover up the pc slot holes, add a false floor to it as you will need this for the wires. and the pc box really is too deep, spray everything black except for the pipes and spark plug leads.

box size is 30cm x 40 cm

Step 5: Wiring

test how it all looks does it look like the flux capacitor in bttf?
are the spark plugs in the right places?

next was to wire up the leds,

i has them in parallel

that means all the plus terminals were grouped together and all the negative terminals were grouped together. this allowed me to play around with lighting it and no fear of burning out the leds at 5v since they are all rated at about 5vs

(Transformer was set at 5V)


once i was happy about how it would look and which colour of leds i was going to use. (red and orange) or Green and Green..

as it gave a nicer glow from the green i went with them.

and went to wire them up in series

this means daisy changing them taking the negative terminal and soldering it to the positive terminal of the next led,  so when i was finished i had one positive terminal not soldered at one end and 1 negative terminal not solider at the other end. all of the 4 leds were now wired in SERIES
and would require 12V to run them.  you can get away with using 3 leds BUT YOU WOULD NEED A RESISTER.

this can be worked out by I/(VxR)

if each LED needs 200mAs and at 12V all that is missing is R

200mA/ 12V = R

0.1666 oham Resister

 but to get away with out a resister just add another led, :D

Note the leds were wired up in series after they were threaded though the holes in the plywood.

TEST the LEDS with Transformer at 12V making sure none of the soldered connections touch. (rap with tape)

Step 6: Show Off

a door can be added if you like, i left mine open as i wanted to see into it, but to add a door just cut some plywood to fit. cut a hole in the middle add some see through plastic, and away you go

this is my finished project.

in the car, with a multimeter i found out which wires become live when the key is turned on.,

then is as simple as cutting into it. running a extra cable from it up to a on.off sw. then from the sw run some wire back to the Flux capacitor. and attach it to your POSITIVE wire. and cover with tape so it does not earth.

then find some where that is connected to Ground on your car  ( to the metal in the car) and connect a connection from it to the NEGATIVE  on your capacitor.

now turn the car on. flick the switch and get up to 88 miles a hour.
then your going to see some serious shit

(dont forget to screw the FC to the floor!!!! )

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    10 Discussions


    5 years ago on Introduction



    10 years ago on Introduction

    Remember to use your time machine responsibly and help your friends.



    10 years ago on Introduction

    This is really cool, but I can't help but think it needs a little bit more decoration. Some little metal pluggy bits would make this look awesome. Well done though, this is indeed an easy to build flux capacitor!


    Reply 8 years ago on Introduction

    oh like its just for show, as a bit of a joke. it cost me more a less nothing to make, and had it wired up in the back of the golf for a while. the next thing i wanted to do was wire it up to the radio signal so the lights would flash intime with the music., but ya your dead right a bit more decoration would finish it off nicely


    9 years ago on Introduction

    Ohm's Law says that R=V/I, you got it backwards...

    Moreover, there are no LEDs rated at 5 Volts or 12 Volts. Most LEDs have a threshold voltage of about 2 Volts but have almost no resistance. LEDs have a Reverse Breakdown Voltage of a few Volts so if you hook them up to AC without a power diode in series you'll burn them up, assuming that they didn't explode because of the huge current in the positive half-wave. LEDs are usually connected to a DC power supply. A 330 ohms resistor is good for 5 Volts DC. 1 kOhm for 12 VDC. Definitely not a good instructable.


    Reply 8 years ago on Introduction

    why dont you just go make your own, and we will rate yours! if you have nothing positive to say shut up! i used LEDS 4 leds in series so i didnt have to use resisters


    8 years ago on Introduction

    HOLY COW - the mother board in the picture I have the same one lying in my junkbox


    9 years ago on Introduction

    dude this is soo sweet i wish it can realy send u thrue time