First of all, this instructable is NOT about how to setup a RetroPie that allows you to turn your Raspberry Pi into a classic gaming machine. There are numerous instructables that show you how to do that step by step so I won't go into that here. What this instructable will show you is how to upcycle hefty Costco fruit cardboard boxes to build a bartop/desktop style arcade cabinet for your RetroPie.

To be honest, I'm very envious of those people who have created professional-looking bartop arcade machines and I don't mind having one of those. That being said, I also don't want the machine to be a permanent piece of furniture in the house. I just want to play from time to time when friends are over or take it to a gathering. For that, I think cardboard-based arcade cabinet is perfect.

The best thing about this project that once you're DONE playing, you can simply recycle the case and reuse all the components for your next exciting project.

** Update **

I've since made another one using the same method for the 2-player horizontal game machine. (see photo).

Step 1: Materials

Raspberry Pi 3 (Zero is also suitable for this project)
Arcade style joystick and buttons (Amazon, Ebay, Aliexpress)
19in 4:3 monitor (This type of monitors are no longer manufactured so you'll have to buy used.)
Amplified mini speaker system with a 3.5mm jack
Cardboard boxes (Get the most sturdy boxes from Costco. I used 4 apple/orange Costco boxes. Two for the case and rest to cut off to reinforce the case)
Glue sticks (You'll need a lot as the case is put together only with hot glue)
1x2 pine wood to reinforce the monitor mount (I think this can be done using only cardboard but I didn't try that.)
Wood board for joystick/button case (Since a joystick and buttons get abused, I used wood board for a joystick and buttons. I've seen cardboard based joystick/button cases but I don't believe these will last more than few games. At least the top surface should be made out of wood or plexiglass.)

Step 2: Controller Enclosure

As I mentioned before, this is the only part where I didn't use cardboard. I don't know about you but I tend to abuse my joystick and buttons when I am playing games so I wanted this part to be strong just like a real arcade machine. I recommend at least the top surface should be made out of wood board/panel or plexiglass.

Step 3: Monitor/Speaker Enclosure

For this, I'm using a Costco "CaraCara" orange box. I think apple boxes are just as good. I reinforced the wall with wood and put in a cross beam where the monitor will be sitting. I think using layers of cardboard glued together to form a beam would be just as good. I also added a shelf for RPi and cables. Bottom is cut to create a backdoor that would give access to all the components and wiring.

Step 4: Install Speakers

Speakers with built-in amp will be located behind a monitor. They are glued to the box.

Step 5: Install Monitor

I'm using a 19in 4:3 Dell monitor with DVI to HDMI connection. This monitor fits perfectly inside the box with less than 1-2 inches to spare. First, you have to remove plastic enclosure to expose baremetal. You may have to relocate monitor control button circuit to rear as I did depending on your monitor.

I use "L" cardboard brackets and a lot of hot glue to secure the monitor. Space between the monitor and the box was filled with several "C" cardboard brackets. Once done, cover up the front with cardboard bezel.

Step 6: Wiring

As I mentioned previously, I am going to assume you have a working RetroPie.

On the back door, I attached a short power strip to supply power to RPi, monitor, and power speaker. My monitor only has VGA and DVI (no HDMI) since this is an old 4:3 monitor so I'm using a DVI to HDMI cable to connect the monitor to RPi. The power speaker is connected to RPi via a 3.5mm jack.

Step 7: Let's Play!

Here are photos of my finished project. I intent on playing only "vertical" games on this machine so I only need max two buttons. (I am not aware of vertical games that use more than two buttons. If you do, please let me know.)