GPi Case Pi3 A+ Prototype Cart

thingiverse

This is my proof-of-concept cart / PCB holder for my attempt to adapt the RetroFlag GPi Case to use a Pi3 A+. This setup isn't a permanent solution but it makes prototyping much easier by allowing me to easily insert the Pi. I'm continually updating this design on my end and will post updates here from time to time once I've made significant changes. Keep in mind that I've never used Fusion 360 or created object models before, so this may be a bit rough around the edges. I've made numerous modifications to this design over time, and if I make another major change, I'll upload that version as well. I've tried to design this holder for vertical printing wherever possible by using lots of 45-degree angles. In theory, it's best printed horizontally, but I've never been able to get the supports off properly in that layout - you might have better luck with that. Also note that you'll need to severely trim down your Pi3 A+ to make it fit. Remove the full-size USB port, GPIO pins, and both ribbon cable points to get it to fit. Regarding the PCB from your GPi Case, you may need to shave this down or modify the model since your board won't be broken apart in the exact same size as mine was. No two cards are exactly the same size, so there might be some tinkering needed there as well. You'll also need to connect the USB pins (the center two) from the A+ to the GPi cart - I used 28 gauge ribbon cable and it worked fine (it's barely passing power, which gets pulled from the main board elsewhere). My preferred method is to wedge your cart PCB into the case, align the GPIO and spring pins, and hold it in place with the cart. Then insert it into the GPi case and use the tension bar between the PCBs and the back of the case as shown in the pictures. It's not a perfect solution, but it makes getting the Pi in place for testing so much easier than trying to hold it against the springs by hand. UPDATE 8-28-2019: https://www.youtube.com/watch?v=1VCH8zh7iYE It's alive! Pictures added and a few details above modified to reflect the working prototype and some steps needed to get your own going. UPDATE 9-10-2019: https://www.thingiverse.com/thing:3850620 Final project is completed and uploaded as its own thing. I'm leaving the prototype board up because it serves its purpose and allows you to test the theory for yourself without fully stripping the Pi3 down. See the link for the files and a full instructables page on doing the mod! I'm removing the work in progress flag since this is as final as the prototype board will get.