Step 2: Wiring of the LED's

Picture of Wiring of the LED's
LED Diagram.png
Some assembly is required for the LED's. I took my round piece of wood that I was using to mount the LEDS on and I started to glue the LED's in the desired places. The circuit from LEDCalc suggested I used 5x 2 LED's and 1 single LED in parallel. This ties in well with the arc reactor so I had the single LED in the middle and the pairs arranged around the edges.

As you can see from picture I made two rings of wire around the edges, the outer wire is 9V and the inner wire is 0V. This ring has the added advantage of providing an secondary route for the power should something go dramatically wrong in construction.

The power wires are passed through the back plate through a small hole, this will allow me to power the LED's when they are encased in the plastic.
althor0154 years ago
Hope some one is still reading these and commenting on them. I am trying to build one of these and am unsure of the wiring schematic.

Which symbols are the resistors and which the lights and how do the outer wires follow the ring?

Bah! Wish I had taken electronics classes!
msraynsford (author)  althor0154 years ago
Still reading and commenting, sadly it sounds like you'd be better off googling for some beginner electronics tutorials.
Neogarex4 years ago
Jason Amigo5 years ago
Since you used one resistor for every two LEDs, did you double the ohms of the resistors?
oud255 years ago
where did u buy the individual smd leds
shilicious5 years ago
Is there a way to make the LEDs pulse? I've seen some other versions of the arc reactor that fluctuated gently similar to the way Tony's does, and I'm not handy enough to know how to do so. Any input would be great! Thanks. :]
syberop55 years ago
what size resistors are u using
is this exactly like on the schematic? if not can you draw a schematic, im trying to make one too because this is great!
This si essentially a schematic; it's ridiculously simple.
daytona5 years ago

Hey msraynsford,

can you send me some of the LED's, polymorph, and the resistors, because my computer won't let me get onto Ebay or Rapid Electronics.

wbbigdave6 years ago
HI, Is it me or is the wiring wrong on the board...from the diagram (from LEDcalc) it shows the resistor 180R in series to the two LEDs on the +V wire, but on yours you have them after the LEDs on the -V wire... Or am I seeing things? Thanks in advance for letting me know I'm being foolish (no sarcasm in this statement, I am very unsure on my electronics)
msraynsford (author)  wbbigdave6 years ago
oh yeah, the wiring is wrong, the whole project must not actually work :P I haven't really checked my wiring against the diagram from LEDcalc but I do know that is doesn't matter which side the resistor is on, as long as it is in series with the LED it won't make a difference. Think of the resistor like a dam in a stream. It's job is limit the flow through the LED. It doesn't matter if you put it at the start of the stream or the end it will still slow down the whole stream.
Heh, Damn you photoshopped it all didn't you!!! :P Cool, like i said my knowledge is very limited, thanks for clearing that up. My parts are on order today, hopefully it should come along quite nicely. Thanks for the great instructable!!!
Hey Martin when you soldered these was the the negative polarity denoted by the notch or the positive (I really don't want to wire these buggers backwards
msraynsford (author)  therealmobius6 years ago
The notch is negative. Don't forget to have lots of testing as you go along, I tested each two LED's as I wired them. As long as you have a resistor in series with the LED's you wont do them any harm no matter which way round the LED is.
wolfman266 years ago
how big did you cut the base, what was the diameter of it?
msraynsford (author)  wolfman266 years ago
the diameter is 75mm, although later ones were reduced to 70mm. This one was cut on a fret saw, although later ones used a hole saw and I put hot glue in the hole afterwards.
wolfman266 years ago
so is that wire just some regular copper wire, something you could find at a wal-mart or something? any particular gauge?
msraynsford (author)  wolfman266 years ago
It's actually kynar wire, but any old copper wire should do the job. I expect wal-mart would have something.
MrManager6 years ago
If I use 1500 mcd LEDs will that make the unit impossible to look at?
some of the lights dont light up around the ring, and in the middle. and when i reverse the electrical flow, the light lights up in the middle. i checked all the soldering points. all the leds are connected to the wire. any responses for a clueless buiider? please respond.
thanks i tried your suggestion and it worked. thanks a lot
Sounds like to me you might have some LEDs hooked up backwards.
I just want to make sure that I understand this diagram completely: The pairs of LEDs...are they soldered with negative wire between the positive points? Or is it negative and positive points? Also, the resistors are soldered to the negative wire. I've never done anything like this before, so it seems to me that the resistor would have to be soldered to the positive wire in order to avoid burning out the LEDs. Thanks for the instructions. This is a great project.
did u solder under the smd leds because the seem so close. if u did solder, how did u manage to do it? is it okay if i just run the wire underneath the connecting point of the smd lights
msraynsford (author)  browncomputerchair7 years ago
smd devices usually have solder points underneath and round the edge of the device. I tried to solder to the side of the devices but as they were upside down at the time I'm sure I got some on the bottom too.
would nothing happen if the solder from the postive end touched the negative end? or would there be a conflict and result in the light not working? by the way, thanks so much for the prompt reply. it really helped me out.
msraynsford (author)  browncomputerchair7 years ago
The ends are on opposite sides of the device, they are unlikely to touch. If the wire did touch you'd get a very quickly get a hot battery and your LED definitely wouldnt light up.
StarkEnt7 years ago
what type of LED's are these? they are tiny? are they SMD?
msraynsford (author)  StarkEnt7 years ago
Yes they are SMD. They come in a PLCC-2 package which has one pin on either side. It gives them a very low profile and quite a wide viewing angle
do you have a site they can be purchased at as no stores seem to carrey them.
msraynsford (author)  StarkEnt7 years ago
Rapid Electronics or Ebay those were the only two places I looked really.
OK I have all my SMD LEDs and I need to wire them up. I see what is up above in the pic and I have read what you did but I guess I am just not getting it. Is there a Diamgram somewhere? With LEDs hook up to he outer wire ring and which to the inner and so forth.
RomanHelmet7 years ago
So I wired all 11 leds up together. The 10 on the outside ring work great, but the one led by itself does not light. Anybody have any idea why this might be? I'm at a loss...and I don't have any more leds left to see if it's just a bad one.
msraynsford (author)  RomanHelmet7 years ago
Is it in backwards? Make up a simple circuit with just that one led and a resistor, then you can connect it to the battery in both directions. If it doesnt light up in either then the LED is dead. Failing that check your connections, you might have a dry solder joint.
paul0301767 years ago
Awesome, I've just ordered all the stuff for one of these! I can solder but I've never tried anything this small, any tips?
I just finished soldering this project together. I know it's not proper soldering technique, but i would put some solder onto the tip of the iron, and then put that on the leads on the leds. Then with the little balls of solder on the leds, I would hold them by the wire and head up the little blob.
Harry Dee7 years ago
Hey sorry but could you tell me what you meant by 'This ring has the added advantage of providing an secondary route for the power should something go dramatically wrong in construction.' and also would you be able to give a diagram of the LEDs and resistors are put together as i can't quite tell how the LEDs are wired from the picture. Thanks!
PcFish7 years ago
Can you make a diagram on how to wire everything together? This is my first time doing this sort of thing and don't want to mess up. It looks awesome Thanks!
dalangalma7 years ago
I have a question - where are the resistors in this photo? Are they the little bumps next to each LED? If so, are they soldered together or did you just glue them in contact? Fantastic instructable, by the way. I'm really excited to try it myself.