How to Make a Google Cardboard VR Viewer, Simplified

Google Cardboard is an inexpensive and DIY means of experiencing virtual reality (VR) using an Apple or Android phone. Download apps to your device, pop it in the ViewMaster-like viewer, and move around to see 360 degrees of real or computer-generated (CG) stills or video.

Google's first and smaller Cardboard viewer was iPhone 5-sized, simple to assemble, and used a pair of magnets to trigger the phone's touchscreen (see the black box above). Version 2.0 held larger phones, could be folded into a rectangular box, and used a conductive button as a trigger. I created this Instructable that uses less than $1 worth of materials, combines the simplicity of 1.0, the size and trigger of 2.0, and (optionally) incorporates one of my favorite electronic tchotchkes, copper tape. This is the "kid-friendly" version that should take one to two hours to make. My more complex and robust version can be found at https://www.instructables.com/Google-Cardboard-20.

If you're thinking, "Why spend time building my own when I can pay a few more bucks to buy one already assembled?" then you are on the wrong website, my friend. Welcome, fellow Makers!

Step 1: Gather Your Tools and Materials.

You will need:

the thinnest corrugated cardboard you can find, like a shoebox or pizza box.
a pair of 45mm focal length biconvex plastic lenses, either 25mm in diameter (GC 1.0) or 37mm (GC 2.0). You won't notice much difference, but 25 mm are easier to get and cheaper, especially if you're willing to get them from China. AliExpress had them in July 2023 at 47 cents a pair (13 cents before shipping!), with a 2-4 delivery time. Expect $2-$6 a pair elsewhere.
cutting tools: sharp scissors and/or a razor blade for straight/outside cuts and an Exacto knife for curves.
fairly weak velcro (squares or circles, about 1-2 inches across).
a rigid metal edged ruler.
a rubber band (1/8-1/4" wide is best).
a glue stick
white glue (Elmers) or tape
copper foil tape for the conductive touch screen button.
a tiny piece of dense foam/sponge (about .25 X .25 X .1 inch), like what some electronics come packed in.

Items 10 and 11 are optional but make the project much cooler.

Other options to consider:

paint your viewer before step 7
make your own head strap out of an elastic or velcro strip
use headphones-- especially for performing arts videos like those recommended at VRforEducation

Step 2: Cut Out Your Cardboard Using the Template As Your Guide.

Print the four page attached in the last step here and glue the pieces onto your cardboard using a glue stick, which will allow you to peel the template off when you're done cutting and folding.

Tip 1: the cardboard is strongest if you glue the template with the "grain" running the longest side of each piece.

Tip 2: To reduce the number of cuts and amount of cardboard needed, you can glue the pieces butted up against each other as I show here.

Cut the pieces on the dark solid lines along the perimeters. Hold off on cutting out the inside blackened sections, like the lens holes.

Step 3: Fold on the Dotted Lines.

Score on (press a dent into) the dotted lines using a metal edged ruler and a dull pencil, coin or pizza cutter, then, pressing the edge of the ruler into the scored line, fold the cardboard toward you.

Step 4: Cut Out Black Sections.

The cardboard was stronger and easier to fold without the inside sections removed, so now you can cut out all of the remaining dark areas (lens holes, forehead semicircle, nose indent), including the slots in the outside frame into which the tabs of the lens frame will go.

Step 5: Optional: Make a Touch Screen Button by First Attaching the Base to the Flap.

The button is a "pyramid" (optional but way cool), stuck to a moveable flap that you'll be able to press down with your right forefinger once the viewer is complete. You'll glue the small piece of sponge (for a soft touch) and lay it over with conductive copper foil tape to bring the slight electric current from your finger to your screen. If you want to skip making this, you can just reach through the nose hole and touch your screen manually. The side of the pyramid that is shorter faces outward, which makes it stand straight up.

Glue or tape the pyramid into the slots as shown.

Step 6: Optional: Complete the Button by Gluing on a Sponge and Attaching Conductive Tape.

Cut a 2 inch long piece of copper foil tape, peel the backing, and wrap it horizontally across the face of the sponge as gently and smoothly as you can. (Tip: Copper tape is best handled by peeling the backing as you need to, rather than all at once. It tends to curl, wrinkle, and stick to itself.) Next cut a 4 inch strip and wrap it from below the sponge, over the top of the pyramid, down past the base, and under the flap.Then cut another 4 inch piece and attach it from the end of the previous piece to the top of your trigger flap, where your finger will touch.

Step 7: Insert the Pair of Lenses

... in the middle layer, both curved side forward. Glue the three lens holder pieces together with the curved nose section closest to you, as shown. Clamping the three pieces together is a good idea until the glue dries (less than 5 minutes).

I recommend you put a piece of clear tape above the nose cutout. No matter how clean we imagine we or our friends are, a forehead grease stain will appear there in no time at all, and the tape will keep it from getting gross looking. Now, if you made this from a used pizza box, the whole thing may have grease stains, in which case don't worry about your oily nose.

Step 8: Assemble the Two Pieces to Make the Outside Frame; Fit the Four Sections Together.

One of the two pieces that forms the outside frame has a semicircle curve to fit your forehead and the other a mountain shaped curve to fit your nose. Make sure that you fold the semicircle piece so that the pill-shaped cut out is on the side shown in the 1st three photos (right, if you were to push the curve against your head). This is where you will use your right pointer finger to push the optional activator button you may have created.

Each of the two frame pieces has a 3 inch folded section at one end and a 1 inch folded tab at the other. Put a bit of glue on the outside of the small tab of one of the pieces and glue that tab to the inside of the longer tab of the other, as you can see toward the right of the 3rd photo here. (This photo already shows the piece with the figure 8 viewing window inserted.)

Once clamped and dried, do the same for the other small tab. You will now have a rectangular frame in which to insert the viewing window, the lens insert, and finally the phone cover flap. This last piece inserts below the phone frame section as shown in the 5th and 6th photo. The design makes the cover flap adjustable to different thicknesses of phone; how far you push it in should be based on how thick your phone is.

As you test fit the four sections, adjust folds and trim the cardboard if necessary to make a good fit. It needn't be perfect! The four sections will stay together without gluing, but feel free to glue or duct tape any section if you prefer something very solid.

Step 9: Install Velcro

Your velcro will last longer and stay put better if you glue a small frame of cardboard on top and put the velcro inside it (avoid glue there so the sticky back of the velcro is gripping cardboard only).

Trace your velcro piece onto this cardboard rectangle and cut out that section to make it fit the "hook" half of your velcro perfectly. Peel the back of the velcro and stick it in the hole you just created.
Peel the back of the "eye" half of the velcro and connect it -- hook to eye-- to the piece on top of your viewer.
Close the lid onto the sticky back of the eye velcro half-- making sure that as you close the top there is a gap in front that will fit your phone.

Adding a thick rubber band to the base of the cover will provide some traction to prevent your phone from sliding out sideways.

Step 10: Download a VR App and Insert Your Phone.

Fire up a Virtual Reality app and insert your phone into the front of the viewer. Fold over the flap to hold it in place. The split in the middle of the screen lines up with the triangular indent(s) in your viewer. If the image looks like you're crossing your eyes, slide the phone slightly left or right.

Here are some sources of apps:

A review of 16 cool apps with pix of old guys using the viewer can be found here.