"Pi-Pad" Home Made Raspberry Pi Device

When I was little I always wanted to make an iPad and understand how it worked. At the time, I had no way of accomplishing this. As I have grown older I now have the tools and knowledge to accomplish such things. I have done Vex V5 robotics on teams 663X and 663C at my school, Chattanooga Christian School (or CCS), and am taking design and programing classes there too for my upcoming 9th grade year. The one limiting factor on my ideas always ends up being the cost of materials or obtaining them. Then I acquired a bin of electronics and different parts from an old arcade project. Inside were switches, speakers and their control board, a screen and its control board, as well as a Raspberry Pi 3B. Now that I had the materials I was ready to design and build my own iPad or "Pi-Pad". Even though it is pretty bulky, I am still very proud of it and the work I did to bring my idea to life..

Fusion 360 , TinkerCad , Raspberry Pi Imager and a device to run them.

Raspberry Pi (3 is what I used but 4 would work as well) + Micro SD card and reader

7inch 40 pin standard screen and control board

Speakers and audio board

Electronic screws and nuts

Screw Driver

Drill and standard 1/8in drill bit

Wireless key board and mouse

Female AC/DC 9v power in

Male AC/DC 9v to USB or USB-C Cable

2x Male to male AC/DC 9v cable

3D printer and filament (I used an Anycubic Vyper and Hatchbox White PLA 1.75mm)

I normally use TinkerCad when I design things, but I decided to use a combination of both TinkerCad and Fusion 360. I used TinkerCad to sculpt out the general shape and to visualize my design. Once I had gone and made the general shape I then sent the design to Fusion 360 and added finer details like tolerances for my printer, screw holes, precise measurements, and other things to improve, finalize and finish the design. In total I would say I used Fusion 360 for about 3/4 of the project and was a really great intro to how to use higher level CAD software, even if it took longer to learn and assemble in.

While Designing this case, I had to figure out a way to make the screen removable and the electronics easily accessible. I accomplished this by sandwiching the screen in-between the ledge on the top half and the big rectangle support the bottom. Then I ran screw holes through the pieces so I can screw and unscrew the two halves.

Whenever I CAD in any software I tend to try to CAD in a way that the project I am making can be reproducible or modular. I made this design to be able to just print a new backplate or front plate if one breaks.

Measurements Used In CAD (Allowing for tolerances):

Speakers: Diameter of 75mm Depth of 40mm (I couldn't get a reliable measurement for the screw holes sop I drilled those out later.)

Screen: 215mm x 130mm x 10mm

I put converted the f3d files into Stl's and uploaded them to Cura Slicer. I then uploaded the Gcode to my printer via Octoprint.

I was having trouble getting the first layer to turn out properly and was having lots of trouble calibrating the printer. Once I had finally gotten the printer calibrated I decided to replace the nozzle with a better quality one, this fixed all of my problems and I was able to print the pieces.

After that I pressed print on the top half and waited for about a day and a half. The print turned out great and I quickly pressed print on the second half. The second half also turned out great and took two days.

While I was 3D printing the pieces, I went ahead and installed the software on the Raspberry Pi. I plugged the micro SD card in the reader and plugged that into my computer.

Before you can write the software to the SD card you must install Raspberry Pi Imager:

Raspberry Pi Imager Download

There are two different options that I would suggest for software (although keep in mind this can run any software meant for a Raspberry Pi and will still work for).

• Lineage OS
• Raspberry Pi OS (or Raspbian)

Raspberry Pi OS is simple to install. Simply open the imager, select Raspberry Pi OS, select your micro SD card, and click write. Then plug the SD card into the Raspberry Pi and provide power.

Lineage is what I will be using and is a little more complicated to install. First download it from this link:

Lineage OS Download

Open the imager and select choose OS. Then scroll down and click upload custom. Then select Lineage OS from your files. After that select your micro SD card and click write. Then plug it in and provide power.

This project was relatively easy to assemble because of the extensive work in CAD that I had already done earlier. Everything really just needed to be screwed together.

The first step is to install the speakers. I lined up the speakers in the slots in the 3D printed case. I then drilled out holes out with the drill and the 1/8in drill bit. After that I screwed in the screws into holes I drilled for the speakers. I then fastened these with some nuts and put on a dollop of hot glue as a thread locker of sorts, since the speakers should be permanently fixed.

If you have a Bluetooth mouse and keyboard now is the time to plug in the USB to the Raspberry Pi. If it doesn't have a USB plug-in you can connect it later in the settings as long as the Raspberry Pi you are using has a built in or external Bluetooth capabilities.

After that screw in the screws into the holes in the case and tighten. Make sure they are fully tightened or the screen may slide around. After that you are done!

Congratulations! You now have a working Pi-Pad device! If you have any problems or specific questions feel free to reach out and I will help where I can.