Introduction: 3d Printed Endgame Arc Reactor (Movie Accurate and Wearable)

Full Youtube tutorial:

I couldn't find any particularly movie accurate 3d files for the Mark 50 arc reactor/housing for nanoparticles so my buddy and I cooked up some sweet ones. It took a ton of tweaking to get the thing looking accurate and awesome. Our early reference pictures were terrible. So we ended up with a lot of revisions. If you want to make your own 3d file to print I am providing all the best and hardest to find reference pictures out there on the web and links to videos of the real prop that will make the design easier. It'll take a good bit of time to CAD up something really nice since you also have to design components to make it wearable if that's the goal. Fusion 360 is free and awesome for modeling tho if you want to put in the time. Fusion 360 makes you think you only get a free trial, but actually if your not a $100K business they let you keep using it you just have to click on the right stuff when it says your trial is over. A free trial of Rhino can allow you to get this done too. That's what we used for most of our work.

Here's a super close up video of the prop by the designer:

If you want to save some time you can get our print files cheap here:

We added a useful optional low profile harness system that keeps the reactor from pulling down on your shirt and thanks to the bunch of neodymium magnets holding it onto your body you can literally do backflips with this thing on and it won't come off. We made this thing as easy to assemble as we could. Our system uses commonly available fairy lights to avoid having to solder anything by giving you 20 leds worth of bright light that matches the same light diffusion pattern as the actual prop. All the parts and paints you need besides the 3d printed parts are easily obtainable on Amazon. If you lack a 3d printer there are likely makerspaces in your area that can help you print up the parts. Some libraries even have 3d printers available. I live out in the middle of nowhere and there are makerspaces even here. You can even buy a high quality 3d printer for under $180 like the Ender 3. A few projects for other people and the printer will pay for itself. There are tons of online services that can print the parts for you too.



Download Mark 50/85 arc reactor 3d files (take your pick):




I Love you 3000 figure download:

chest strap (there's a lot of these so look at the reviews and prices):

Magnets 6mm x 2mm:

Fairy Lights 20 individual lights cool white: (You can get smaller packs. I bought in bulk to make a lot of reactors cheap)

Clover colored alcohol ink:

Stonewashed colored alcohol ink:

Polyacrylic (probably get the spray locally at a hardware store) this kind would require air brush

TPU filament



Sand Paper

Rustoleum 2 in 1 sandable filler primer (probably cheaper locally)

Clear ABS filament

Alternative to clear ABS clear PetG

Tooth Picks

Drill bit 1/8"

Step 1: Print Parts

You'll want to print the parts in high resolution to save yourself cleanup time. For all the parts except the diffusors and electronics panel I printed at a .12 mm or .05 mm layer height with a .4 mm nozzle on my CR-10. I did three shell layers and about 17-25% infill. You want to do a lot of top and bottom layers especially if printing in TPU. I did like 7-10 to and bottom layers depending on layer height (more if layers were thinner). For the electronics panel I printed on .12mm layer height with a 100% infill. On the inner diffusor I printed it with a 25% triangular infill at .2mm layer height with 4 layers on top and 4 on the bottom with just one shell. This infill pattern is needed so the triangles can be seen when the light shines through like the real prop. On the outer diffusor I had the infill set at 40% on the honeycomb pattern to get the movie accurate pattern. The diffusors must be positioned like I have mine here to get the right orientation on the polygons. Your slicer may be a bit different. I used Simplify 3d (and yes it's worth every penny for serious printers). I used supports and helper discs and printed directly to glass using a little glue stick.

For the best and most durable prints I suggests using TPU (the Vibranium of plastics) for all the parts but the diffusors and electronics panel. Those should be made in a clear ABS or PETG. I literally ran over the TPU grill and body like 10 times and it did nothing. So take comfort in the fact that if someone runs you over the arc reactor will probably be fine. For comfort the parts on the body harness really should be TPU because of its flexibility. You may be tempted because of a misinformation campaign by plastic powers that be to print in the evil TLA known as PLA. PLA is garbage plastic for dirty peasants and will warp if left in a warm car or if you even question its clearly poor life choices with the softest of constructive criticisms. "But PLA doesn't warp on the bed"... yeah, 'cause it doesn't deal with its deep seated issues and just keeps them pent up to release them all at once at a later time. PLA will only bring dishonor to your family. Make a note of this: PLA will bring dishonor on you, dishonor on your cow....Seriously it's %^*$ plastic.

Step 2: Main Body and Front Grill Assembly and Painting

You'll need to superglue the front grill to the main body. This glued part will need to be coated with filler primer with a medium coat. Leave time to dry and wet sand the whole thing with some 400 or 600 grit wet sandpaper. Try and fill in the worst of the layer lines and stepping marks with some super glue. Use caution to not lose too much detail in the process. We lost some details that looked better in the starting print in some areas. If you take your time you can get it a bit more movie accurate than we did. Getting the layer lines and stepping to totally go away will probably take about 5 cycles of coating and sanding.

You'll need 18 of your 32 6mm (diameter) x 2mm (height) neodymium disc magnets for the main body. You'll want some kind of fairly fast setting epoxy (like 5 min-10 min work time) mixed up to glue the magnets in place according to the pattern provided. You'll want to mark one polarity of all the magnets with a permanent marker to keep track of their direction while gluing. Just be sure to leave ample time to dry your mark before restacking them so you don't get confused. Leave plenty of space between them while marking or they will all just fly together possibly marking the wrong side of the magnet. Yes, I learned that the hard way. It may be best to glue one orientation of magnet 1st then the other because the magnets can pull each other out easily when they are both still wet and side by side resulting in lots of swearing and an unquenchable rage. When done with this step coat the back of this part with filler primer to prevent light leaks later.

I'm showing how I painted it but I think there exists a more movie accurate and cooler way to do it. This link shows how on Coregeek Creations

I used some spray paints for polycarbonate because it is a harder plastic to bond to so I figured that paint would bond well to my primer and it did. The Tamiya or Duratrax silvers look pretty good especially after the black wash I used is applied. I did about 3 or so light coats of silver leaving adequate drying times between coats. Then I did the gold details with a brush using Testors gold.

I used Polyacrylic semi-gloss paint to seal the whole thing. Like 2 or 3 coats leaving adequate drying time should work. I'm unsure if you'd want to add this with the graphite technique. Some vids make it sound like the graphite doesn't rub off easy after having buffed it a bit with a cotton ball, but I'm unsure without doing it myself.

The prop must be covered in a black acrylic wash to make it look like the real prop. I made a wash from a mix of equal parts satin black acrylic paint and water. The brush must be washed into all the areas of the prop and wiped off with a wet paper towel until the desired look is achieved.

Step 3: Magnetic Back Plate and Harness System

Glue in the magnets on the magnetic backplate with epoxy with the same polarity orientation pattern you used on the main body. Find the center fo the chest strap and mark it. Mark the center of the upper part of the magnetic backplate and magnetic chest strap cover. Glue the 3d printed parts to the chest strap so they are centered and so the strap does looks like it does in the pictures. Though optional this strap system will keep the arc reactor from looking awkward from it pulling down on your shirt as you wear it.

Step 4: Adding Movie Accurate Lights-Electronic Panel Assembly

Hot glue the cool white fairy string lights using the CAD diagram as a guide. There will be a lot more wire between the lights than my diagram makes it appear, but there is plenty of room to tuck that wire away in the electronics panel. The lights fit tighly in the plastic slots designated for holding them. Just make sure your lights actually emit the light in the right direction when you stick them in. You don't want your lights to point one way on one side of the arc reactor and be pointing slightly in a different direction on the other side. Check your work as you go.

Once you get it all sorted you'll want to make sure your last two neodymium magnets get glued in the right way to hold the panel to the main body. Then cover up all the wiring with the electronics panel cover. I just glued the cover in with hot glue and super glue. Avoid using hot glue on the magnets the high temperature can partially demagnetize the magnets.

Glue the battery box as seen in the pictures w/ superglue. The position is important so it sits properly on your chest and so the on/off button is easily accessible even when being worn.

Step 5: Assemble and Color the Light Diffuser

You may have to lightly sand the inner diffusor triangle to get it to fit. It should fit snugly. You can glue it in or use a big piece of packing tape (what I did) on the inside to hold it together better.

To get the right look you want your parts to look like glass on the side that is exposed. I got pretty good results printing directly to my glass bed but it wasn't enough. I got it to look right after wet sanding it with 300 grit sandpaper all the way up through different grits until I hit 2000 grit. Leave the back side as rough as you can to help with diffusion. I actually added a few little triangles of wax paper glued to the back of the inner diffusor to help make individual leds less noticeable.

You'll need an airbrush for this next part. You can get cheap airbrushes that you can blow into or that work with little compressed air canisters that would work fine for this if you lack access to a setup. Crayola even makes like a $20 one you could probably hack to work. A good setup w/ an air compressor can cost as little as $80 bucks tho and will serve you on a crap ton of projects.

After a lot of fails to make this part look like the movie one using paints I finally found that using alcohol inks nails the clear look that allows the infill patterns to shine through. The clover and stonewashed Ranger inks I used get the colors just right. I did a thin pass of blue on the front and back. The actually prop is a green color with a hint of blue when turned off. So I used the clover ink in a bit of a heavier coat to get that look. Although my picture makes it look very blue it actually has just the right color to match the movie colors when done the way I did it. Don't be tempted to coat it with polyacrylic. It messes up the ink.

Step 6: Snap It All Together and Enjoy!

Step 7: Future Versions and Improvements

I already have a functioning wireless charger version as seen here. It can even charge through a case. The tutorial vid has been filmed and an Instructable will be written for it as well.

There is a cool statue Nikko Industries made using a variant of our arc reactor. You can download it on his site. His base isn't wearable like ours but if you have his statue printed it can fit our arc reactor base for the best of both worlds.

Next up a real laser/blue fire unibeam and much more. You can support us on Patreon to keep the dream of making amazing props and 3d prints alive.

Happy Building!!!!

Give me ideas for future arc reactor features in the comments!