my arc reactor tutorial/guide

A lot of people have messaged me asking me how I made my Toni Stark arc reactor, so I decided to write it all down in hopes that it could help some other aspiring cosplayers!

DISCLAIMER: This is only a guide showing you how to do this project exactly as I did. There are many other (probably better) ways to do this. The methods I used, and the safety of them, are dubious at best, so take caution in performing any of these actions I have described. Please talk to an electronics expert before attempting any wiring/soldering. Please don’t repost this on any other site without a link to this blog.


  • Iron Man 2 arc reactor toy

this was a toy that came out for the Iron Man 2 movie. You can find this on ebay or amazon for around $10. (a modified Avengers version is in stores now, but it doesn’t have the Mark VI triangle look we want.) The reason why I didn’t just use this by itself is because the unmodified toy has yellow lights that only glow temporarily, and that’s not very screen accurate, is it? :P

  • one SMD-LED G4 disc, preferably with cool-white 10-SMD (aka 12 LEDs)

SMD means Surface Mount Diodes, these LEDs are flat, unlike the rounded bulbs you’re more familiar with. These are tiny little things, but they are BRIGHT. I got a 10-SMD from ebay (this one) and two 9-SMD discs for my repulsor hands from dealextreme. Dealextreme is a lot cheaper BUT shipping takes a few weeks because it is made in Hong Kong.

  • soldering iron. I used a cheapo one for around $15 from Radioshack
  • 9V battery snap connectors, you can get this at any Radioshack or a similar store
  • 9V batteries. You can pretty much buy these anywhere.
  • solder for your soldering iron
  • a tiny Phillips screwdriver to take apart the arc reactor toy
  • hot glue
  • silver paint, either from a spray can or you can paint with a brush
  • craft foam, the thin kind you would use in school
  • plastic paint roller tray, it needs to be white
  • scissors
  • either electrical tape or heatshrink
  • spirit gum (optional) if you want to attach it directly onto your chest/skin

Once you have all of these things, it’s time to start by taking apart the shell of the toy.

Go ahead and dump everything except the shell of the toy and the light screen. I know, it seems like a waste, but it makes for a flatter prop and you don’t need all that other junk anyway. We will be painting the shell of the toy with the silver paint so it looks more like Tony Stark’s.

So paint the shell outside/wherever you paint things and let it dry for a day or two. We don’t want the paint smearing or sticking to things. Leave the light screen as it is.

Moving onto the electronics side of things, set up your soldering iron, your solder, a damp sponge, and have your light disc and battery snap connector at hand. This should all be done in a well-ventilated are. Don’t attach to the batteries to the snap connector yet. Watch a tutorial (or five) on youtube on soldering basics. Also make sure you read the instructions that come with your soldering iron. Don’t do anything before you know exactly how to do it.

Soldering irons heat up very quickly, so be careful. Basically, what you’re going to be doing here is connecting the pins from the light disc to the wires from the battery snap connector. This is why we need solder. Watch soldering videos on youtube, research basic soldering, and you will understand all I am about to say.

I lined up the pins of the light disc to the wires of the snap connector, so that they were touching sort of side-by-side. Usually, you would twist the wires together, but I didn’t know this at the time, so ~I did it my way~.

Then, I took the end of the solder wire and placed it to the tip of my heated-up soldering iron. The solder melts instantly to the tip of the iron, this is called tinning. If you do this, watch out for smoke/fumes, wear a mask and/or keep your head away from the smoke. 

Next, you want to place the soldering iron and the solder near the connected battery wires and LED pins. Melt the solder onto the connected part. The solder needs to be spread around so that it’s covering both the pins and the wire.

Here’s a terrible drawing showing what I mean. The solder cools almost instantly when you remove the heat source. The first pin is connected to the first wire with hardened/dry solder, and you would connect both. The light disc and the battery snap connector are completely connected now.

Snap your battery in and you should be enjoying your new temporary blindness from the light. I covered the connected parts with electrical tape so that it’s more sturdy, and also so I don’t have any shocks/wires shorting out/whatever. One could also use heatshrink, but I didn’t so I can’t help you there.

Back to the arc reactor shell! When your paint has dried, bring the shell inside, slide the light screen back in there, and have your LED disc ready. Having the LEDs under the toy screen looks perfectly OK by itself, but to get the diffused light look that the movie arc reactor has, I cut out two circles of thin plastic from the plastic paint roller tray and stuck them in the inside of the toy behind the screen. It gives a much more glow-y effect. I also put black electrical tape on the inner sides of the toy, so that light doesn’t poke out from the little vents on the side of the toy.

This is the part when I just abandoned all common sense and started hot-gluing things. I cut out a piece of foam that matched the size of the toy shell, and made a little border to hold the light disc steady in the middle of the toy. I hot-glued everything down. Everything. You probably shouldn’t do this.

My prop has the battery wires poking out so that I can stick the battery into my shirt and easily replace the battery if it dies. If you don’t want this look, you’ll have to figure out some way to stick the battery in there too. Then I glued the edges of the toy shell to the foam, so the light disc is inside the toy shell. This completes the arc reactor. IT IS FINISHED~

(a note about attaching it to your chest- if you have boobs, place the arc reactor ABOVE the cleavage, where it’s still flat, otherwise the arc reactor will not stick completely to the skin as there would be a gap.)

  1. re4rences reblogged this from ladyvengers
  2. herobyaccident reblogged this from ladyvengers
  3. silvermusicnotes reblogged this from ladyvengers
  4. rendywithawhy reblogged this from whatthepatrick
  5. whatthepatrick reblogged this from hackedmotionsensors
  6. followingskinna reblogged this from ladyvengers
  7. goldcast reblogged this from ladyvengers
  8. cosplay-city reblogged this from ladyvengers
  9. prussia88 reblogged this from pikachusthef
  10. pikachusthef reblogged this from ladyvengers
  11. weababes-pro reblogged this from ladyvengers
  12. the-storm-of-the-century reblogged this from ladyvengers and added:
    whos-flying-this-tardis, as per our current conversation. The only question is could we figure out how the hell to do it...
  13. ifeellikeanewwombat reblogged this from ladyvengers
  14. prestidigital reblogged this from seaweedforbrains