Companion Cube Storage Box




Introduction: Companion Cube Storage Box

About: We are a couple that loves creative projects, and retro gaming. We will be posting anything that we make related to it, with DIY videos, crafts, projects, retro gaming, build logs and showcases. Make sure t...

I've never worked with foam in a project before, so I figured I could try to make a storage box that looks like a Companion Cube from Portal to test that out! Here's what we'll need:

Supply list:

Tools used:

  • Circular saw
  • Table saw
  • Scroll saw
  • Wood glue
  • Nails
  • Drill
  • Clamps
  • Sander - rotary / belt
  • Paint brush
  • Hot glue
  • Soldering iron
  • Scissors + utility knife

Step 1: Sketching and Planning

As this project requires quite a lot of different layers containing different materials, we'll make a sketch just to keep our minds clear and know what goes where. Also, it can be smart to make a 1:1 sketch with all the measurements for the cube and the different components. Check the .pdf or .psd if you want to see all the layers one by one!

Step 2: Cutting the Pieces to Build a Box Base

First of all, we need to make a basic box out of MDF that we can work with as a base for the cube. We're cutting two pieces for the top lid and the bottom, four sides, and four legs out of a wooden rod. We now have all the components to make the simple box.

Step 3: Assembling the Box

We attach the legs with screws, and make sure that it's rigid against the table before continuing. We can then use wood glue to glue the four sides. Just to make sure it won't fall apart later, we'll add some nails to secure it. Well leave some clamps on there until it's completely dry, and then we glue the square we have to the bottom. Now we have a simple box with a lid.

Step 4: Adding Circles Underneath the Hearts

We have to raise the hearts up a bit, so we'll cut six round pieces of MDF to fix this. Fist we use the table saw to cut out squares, then rough circles with a scroll saw, and finally we use a sander to touch up the edges. All of these we can glue to the sides of the box.

Step 5: Last Touches on the Lid

We're almost done with the MDF - we're just going to add a square to the underside of the lid so that it will slide into the tracks of the box without moving around later.

Step 6: Painting the Box

As we'll add acrylic glass later, some of the MDF is going to be visible in the end result - and since the Companion Cube has got pink hearts, we'll use pink acrylic paint on all the areas that will be covered with acrylic glass later. This way it will look pink no matter if the lights are on or not. Also, painted the inside black just to get rid of that brown colour.

Step 7: Cutting the Acrylic

Time to fix the glass! We need 24 small rectangular pieces in total, and 6 round ones. The scroll saw is all we need to cut it. As we want to be able to see the light when we glue it to the edges, we have to sand all of it down with a sander.

Step 8: Gluing on the Acrylic

Now we can use hot glue to glue on all of the acrylic!

Step 9: Adding LED Strips

I'm using a pink LED strip for this - I didn't really want to make it RGB as I prefer the original look of the cube, but it's totally an option here. We just have to cut it into short pieces that we solder together with some wire, and then edge light all of the acrylic. We just need hot glue to attach them.

Step 10: Creating a Completed Circuit That Powers the Lid

Now, we want to be able to take off the lid whenever we want, while still being able to complete the circuit that gives power to the LED strips on the lid. The solution we'll go for is contact points! We can add two screws to the lid, and two metal pieces to the box that will rub against each other when the lid is on. We can then cut off the tips of the screws on the lid, and solder some wires from them to the LED strips. Just checking if it works, and it does! The screws only required a bit of tweaking.

Step 11: Adding the Rest of the Electronic Components

We need to power this thing somewhere, and first I added a regular power plug to the bottom of one of the legs. I figured out later that it would be cool to be able to make the lights fade and flash, so I went back later to change the power plug with an LED controller - if you're making this RGB, you'd want one of those anyway - but I'll get back to that. You could just leave it like this, though!

Step 12: Creating the Hearts

So, what we have to do next is cover up the whole box with foam and actually make it look like a Companion Cube. First, we'll make the hearts in the center - we need to cut a circle from a 3 cm thick foam, and then cut out a heart in the middle. The shape can be quite rough, as we'll cover it all up with a 1 mm thin white foam afterwards. Again, we use hot glue to attach them to the cube; now it's starting to look like something!

Step 13: Covering the Surfaces

The larger surfaces we can cover up with the thick foam, and then the grey EVA foam on top. We just have to leave some room for the pink lines coming out from the hearts, and cut holes for the legs.

Step 14: Making Corners

We make the corners the same way - thick foam as a base, and thin foam covering it. It's a bit harder to shape, as the corners are more complicated than the other pieces we've worked with. We need hot glue to make a corner first, and then use a marker to mark where we have to cut. Tried using a utility knife for the detail cuts, but the scissors were easier to use here. The utility knifw worked better for large, straight cuts. When we've covered it up with white foam, we can glue it on to the cube - it even covers up the legs perfectly!

Step 15: Making Side Angles

We make the side angles just like the corners - the main difference is that we have to use the utility knife to cut it down the middle so it's half the thickness of the corners.

Step 16: Adding Handles to the Lid

The lid is quite heavy, and as there won't be any good ways to lift it up without ruining the cube in some way, we'll add two handles that will make this easy. Now we can avoid damaging the foam later.

Step 17: Breathe, Have a Coffee

It's been really time consuming up until this point - relax a bit, look at how far we've come, have a coffee, and continue!

Step 18: Doing Some Changes

As I said, I changed the power plug with an LED controller. So, we have to cut a hole in one of the corners that we'll hide the controller in. We're making sure that the signal cable is reachable from the front, and that the power input is accessible from the back. When the corner is covered up, it actually looks pretty slick.

Step 19: Assembling the Last Pieces

The last thing to do is to cover up the rest of the MDF surface with foam. To be able to put the lid on we have to cut 45 degree andles on both the box and the lid - and it sits nice and flush when we're done. All we have to do now is add the rest of the corners and angles!

Step 20: Finished!

... and it's done!

What I experienced is that foam can be kinda hard to work with, because it's not so easy to cut out details. Anyway, we got all the shapes we wanted, and even if they're not perfectly symmetrical, the overall look feels like a proper Companion Cube. It was a fun project, at least, and now I have an awesome storage box!

Hope you enjoyed the project and the read, and if you make / have made something similar, I'd love to see it!

Make it Glow Contest 2016

Participated in the
Make it Glow Contest 2016

1 Person Made This Project!


  • Lighting Challenge

    Lighting Challenge
  • Colors of the Rainbow Contest

    Colors of the Rainbow Contest
  • Puzzles Speed Challenge

    Puzzles Speed Challenge

2 Discussions


3 years ago

Got my vote!


Reply 3 years ago

Thank you!