Google Pineboard

You may have heard of Google Cardboard. This is a clever little Google project that allows one to use a smart phone as a virtual reality headset. Virtual reality was that on-the-edge immersive technology we all remember being hyped in the early 90s, just before the internet took off. By folding a bit of cardboard around a phone and a couple of plastic lenses, a sort of stereoscopic viewer is created, not unlike those I'm sure you've played with in antique stores. The phone's accelerometer tracks your head movement without any lag. The experience is otherworldly, and available apps provide 360 degree photography, stereoscopic movies, and virtual roller coaster rides.  You can even use this device to view 3D models and designs using Sketchfab.

I was curious about testing this gadget, but wasn't about to pay the 200 kr local retailers want for a kit. The concept is sold as a "DIY" project, but let's be honest here: who's got 43mm focal length lenses kicking around? Searching online for the lenses, I found a kit for less than 30 kr that would be delivered to my door from Hong Kong. So I pulled the trigger and placed an order.

While the cardboard in the kit isn't from a pizza box, after a week of using it and sharing it with friends, the accumulated skin grease certainly makes it look like one. So I set about making a replacement for the case with some wood I had kicking about:

Here are the materials for the project: a Google Cardboard kit including lenses and magnets ( to trigger a magnetometer for device input), my phone, and a couple of surfaced pine boards, one unfortunately flat-cut about 8mm by 95mm, the other 15mm by 21mm. I also had a scrap of 1/8" birch plywood I would use for the faceplate. Dimensions were based upon the original cardboard, my phone, and the materials at hand. I didn't even bother making any drawings beforehand.

I started by plowing a groove to fit my phone in the center of the smaller stock. I cut a length and plowed two parallel grooves, as I didn't have a cutter the precise width needed. To hold the small piece of stock I used a small metal vise. The final groove was cleaned with the chisel. This operation would be better performed on a wider piece of stock that would then be ripped to width. But I improvised and it worked OK.

I then used the same plane to plow a pair of small rabbets to join the phone-holding stock to the side stock. I cleaned the joint with a small side rabbet plane. I also plowed a groove in the side pieces to hold the faceplate. If you do not have a little plow plane, this design may have to be modified. Perhaps some aluminum or brass extrusions could be used to hold the phone and faceplate? Or use a saw kerf and narrow chisel to do the same job?

After cutting all the stock to length and shooting the edges with a low angle block plane against my bench hook, here's a mock-up of the assembly. I planned to dovetail the case sides together, leaving the bottom piece shifted slightly outwards to support the bottom of the phone when it is slid into the flanking posts. There are many resources on the internet to aid one in cutting dovetails by hand: Google is your friend. I laid out by eye and with a bevel gauge, and used a cheap dozuki saw and a 1/4" chisel to cut the tails and pins.

Predictably, the flatsawn side pieces split along the groove for the faceplate when chopping the pins. The only thing to do was to repair it with some PVA and clamps while holding it in place in the joint.

Here's a dry-fit of the assembly with the phone in place and the Cardboard app running, to ensure that the image is centered on the center of the headset.

After cutting all the case pieces, I made the faceplate from the 1/8" plywood. The lenses were exactly 1" (25.4mm) in diameter, so I used a 1" forstner bit to form the eye-hole and the bridge of the nose. While I had the brace out, I used a 20mm bit to cut the peak of the nose on the lower case, as well as sink a recess for the 19.5mm magnet. (For my telephone model, a Sony Xperia Z2, the magnet function works best on the bottom right of the device, as opposed to the left temple location that is standard in Cardboard kits.)

I then used a coping saw to  carefully shape the forehead and cheek curves of the upper and lower parts of the case before assembly.

A whole mess of clamps eased assembly, which probably could have been done in stages.

I gave the viewer a light test coat of a raw linseed oil-beeswax mix followed by a light rubbing of shellac.

During testing, I realized I'd forgotten the secondary nosepiece, which prohibits stray light from disturbing opposing eyes' viewers. I cut a piece from a scrap of plywood and epoxied it in place.

Final shaping of the curves and smoothing of edges was done with a rounded rasp, file, and sandpaper on a cork.

The finished viewer. I painted the inside of the case with some flat black acrylic craft paint we had, and gave the outside a couple coats of linseed/beeswax/shellac. I secured the lenses with some silicone, but may end up using epoxy if it does not hold.

All the tools used in this project: not a huge investment, and all very compact and quiet to use: perfect for apartment woodworking!

All in all, this was a fun practice project. Google cardboard is a perfect way to dip one's toes in virtual reality technology. It's fun to share the experience of riding virtual roller coasters or flying in Google Earth with friends, and this wooden case will certainly hold up better than a piece of cardboard.