How I went from expensive cloud bills to a custom, 3D-printed home server rack.
You’ve probably heard that the cloud is the only way to run modern applications at scale. But here’s the truth: for many workloads, the cloud is becoming an expensive, bloated necessity rather than a strategic advantage. I’ve been looking for a better way, and that led me to build a bare metal Kubernetes cluster in my own home office.
It started with a simple problem: my AWS bill was spiraling, and I knew I could self-host many of my development environments and side projects. However, moving away from managed services comes with its own set of challenges, particularly when it comes to hardware stability and thermal management.
The Problem with Stacking Mini PCs
When I first started this journey, I simply stacked three Minisforum UM790 Pro mini PCs on my desk. It worked—until it didn’t. The heat buildup was significant, leading to thermal throttling and intermittent instability in my cluster. A cluster is only as good as its uptime, and my “stack” was proving to be a bottleneck.
I realized that if I wanted to rely on this setup for serious work, I needed a proper housing. Since commercial server racks are built for massive enterprise servers, not compact desktop hardware, I decided to build my own solution. This led to the creation of the TinyRack, a 3D-printable modular mini server rack.
Why I Moved to Build123d
Initially, I designed the components in Fusion 360. While functional, it wasn’t flexible enough for what I wanted: a truly parametric system that others could easily customize. I switched my workflow to Build123d, a powerful Python-based library for CAD.
By using code to define the hardware, I’ve been able to create web-based generators. This allows you to generate custom-sized models tailored specifically to your hardware footprint. The project is open-source (MIT licensed), and you can find the source code and generators here.
Building a High-Performance Bare Metal Kubernetes Cluster
Hardware is only half the battle. To ensure my bare metal Kubernetes cluster actually performed, I had to get creative with networking.
Each of my nodes is interconnected via a high-speed USB4 mesh network. This provides low-latency communication between the nodes, supplemented by a standard Ethernet connection to a TRENDnet 8-Port 2.5Gb switch. To keep an eye on the health of the hardware, I’ve integrated JetKVM modules for remote management, using a 3D-printed mount to keep the cabling clean.
“A cluster is only as good as its hardware foundations. Don’t underestimate the impact of thermal stability on your orchestration layer.”
Common Mistakes in Home Lab Projects
If you are thinking about building your own rack, here are a few traps I fell into that you should avoid:
- Ignoring Airflow: Even if the hardware looks “cool,” it needs room to breathe. Always design for passive ventilation or add fan mounts.
- Over-complicating Connections: Stick to standards where possible. My USB4 mesh setup was fun but required careful driver configuration.
- Lacking Modularity: Don’t build for today’s hardware only. Build a frame that can adapt when you inevitably upgrade your mini PCs next year.
Future Developments for TinyRack
Now that the core system is stable, I’m looking at the next phase. Should I prioritize a full enclosure to deaden noise, or focus on a modular vertical mounting rail that mimics standard 1U server racks? The goal is to make the system as flexible as a data center rack, but at a size that fits on your shelf.
If you want to try printing your own, check out the models on MakerWorld or Printables.
Key Takeaways
- Move Beyond Cloud Costs: You can significantly reduce overhead by moving non-critical workloads to a local bare metal Kubernetes cluster.
- Embrace Parametric Design: Using code-based CAD tools like Build123d makes your hardware projects far more reusable and accessible.
- Prioritize Thermal Management: Don’t just stack hardware; proper rack mounts improve longevity and stability.
- Start Small, Iterate Often: Build for your current needs first, but design your infrastructure for future expansion.
Ready to start your own build? Grab your favorite filament and check out the full assembly documentation to see how the system comes together.“,