The Raspberry Pi 4 packs an amazingly inexpensive computer onto a credit card-footprint board. However, the stock Raspberry Pi 4 overheats during normal use and throttles its own performance. When 219 Design started working with the Pi 4 (for live video portals between offices), we quickly needed our Pis cooled, so we designed a Raspberry Pi 3D printed case. We’re not the only ones experiencing this. The blogosphere is ripe with descriptions of Pis overheating, see these articles:
To quantify the issue, we performed stress tests on the CPU (Central Processing Unit) and GPU (Graphics Processing Unit). To max out the CPU, we used a script called Stressberry from pypi.org and Temp_test from Explaining Computers. To max out the GPU we used OpenGL 2.1 Test from Geeks3d and Open GL’s Shader demo. We then ran these stress tests while measuring the CPU temperature from Pi 4’s built-in temperature sensor and while measuring the GPU’s frames per second.
As the above figure shows, the stock Pi 4 will heat into throttling even with heat sinks connected to the CPU and GPU. In order to reach full performance from our Pi 4s, we made a case with a fan.
Across all disciplines, 219 Design focuses on rapid feedback loops, particularly in the beginning of a design process. For this case, we prototyped using a MakerGear M3 3D printer. Although these prototypes lack a polished finish, it was well worth the speed of design iteration. We designed the following Raspberry Pi 3D Printed case which is available to the public for free download.
Our case is designed for two modes.
After experimenting with a few geometries, we settled on cantilever snap fits for both the base-to-lid and the fan-to-lid connections. To keep the snaps from shearing off where they meet the lid, which is particularly likely due to the layering of FDM printers, we added a fillet and widened the snaps’ base. For more on snap-fits, check out BASF’s guide.
These snaps eliminate the need for fasteners or hinges. Because our in-house 3D printer has just fine enough resolution to make the snaps, the details add nearly no extra cost to the manufacture of part.
The envelope of the case is just barely large enough for the Pi 4, which minimizes its footprint on your desk.
In addition to the design touches, our 219 case successfully serves the primary function of cooling a Pi 4. As seen in the figure above, equipped with our 3D printed case and an inexpensive Pi fan, the Raspberry Pi 4 stays well cooler than the throttling limit during our stress tests. Also note, the Pi stayed cool without heatsinks. Save a few bucks and skip the heatsinks!
Prototyping this case with 3D printers allowed:
If you want to accelerate your development and reduce costs, contact us!