The family is planning a long road trip. We want to give the kids some movies to watch to keep the peace in the back seat. I figured my Surface Pro 3 would make a good device for watching movies, I just needed a way to mount it. I wanted it to mount between the seats so it could be viewed easily by either seat in the back. Turns out there aren't any good options for mounting a device that large in the car. So I decided to make one from whatever scrap I had in the garage. It's not pretty but it's quick and cheap. Total cost: $0.00. Note: this build is for cars with adjustable headrests.

Materials

3/4" plywood
3/8" plywood
1/8" MDF
1/2" copper tube straps x 2
screws x 12
hinge
packing foam or felt
wood glue
spray glue
T-nut and bolt or wood screw

Tools

drill
screwdriver
saw

Step 1: Make the Support Bar

Measure the distance between the inner posts on your headrest. Mine measured 24". Add 2" to give yourself space for the mounting brackets. Also determine how tall of a piece you can fit under the headrest. I opted for 2" to keep it plenty strong and stable. Cut out the piece in 3/4" plywood. Mine ended up being 26" x 2". Test fit it in the car before proceeding.

Step 2: Add Mounts

Put your support bar in place and locate the tube straps. Mark where the holes are. Drill holes for the screws and screw in one half of the strap. Wrap the headrest post in packing foam to give a nice tight fit and prevent scratches and squeaks. Screw in the other end of the tube straps. Mark the center of the support bar and locate the hinge. Drill and screw the hinge in place along the top edge of the bar.

Step 3: Make the Tablet Support

We are going to make the tablet support out of 3/8" plywood. Measure the vertical height of your device while it is in landscape mode. Mine was 8". Add 3/4" to that measurement to allow for top/bottom ledges. Cut your 3/8" plywood to that length. The width isn't important. Keep it wide enough to provide good support. Mine measured 8 3/4" x 4 3/4". Adjust the measurements as needed to fit your device/materials. Cut two small strips of plywood 3/8" wide. Glue them to the top and bottom of the tablet support. Place the tablet support over the hinge of the support bar and position it for best viewing. Mark the hinge location. Drill the tablet support and screw it onto the hinge.

Use spray glue to attach the packing foam to the tablet support. Cut two thin strips of 1/8" MDF 5/8" x 4 3/4" to serve as a lip to hold tablet in place. Glue the top strip in place. We need the bottom strip to move so we can get the tablet in and out easily. Screw one end in place and cut a slot on the other end to fit over a screw shaft. Glue a strip of packing foam on the bottom strip to protect the screen and hold the tablet tight.

Step 4: Mount and Adjust

Put your new tablet mount in place. To adjust the vertical angle, I drilled a hole through the support bar, inserted a 10-24 T-nut and screwed in a bolt. The angle can be adjusted by turning the bolt in or out. You could do the same with a simple wood screw or just fasten a wedge under the hinge. The horizontal angle is not readily adjustable. If needed, tweak it by putting washers under the hinge.

Finish things up by sanding the edges to prevent splinters and protect the upholstery.

Step 5: Enjoy

That's all there is to it. It took me less time to make it than I spent on the internet looking for a commercial version to purchase. Despite the obtrusive look, the setup did not impede my view out of the rear window at all. I added a power inverted to keep the tablet charged and a pair of headphones to keep things quiet. 14 hours and 1000 miles in the car and it held up perfectly. No vibration, no dropped tablet. The kids approve.