Flux is built to help you move fast—from idea to fully routed board—with powerful automation, AI-assisted design, and intuitive tools that make professional workflows accessible to everyone. But even the best tools come with a learning curve, and occasionally you might run into something unexpected.
This guide is here to help. Based on the most common questions we hear from our users, it walks through practical solutions to unblock your designs and give you more confidence as you build.
Whether you’re new to PCB design or just new to Flux, these tips are designed to save you time and help you get the most out of the platform.
“Why am I seeing DRCs for overlapping copper?”
Overlapping copper errors typically occur when copper from two different nets occupies the same area on a PCB layer. This can lead to short circuits, unexpected connections, and compromised board performance. Flux flags these cases as design rule violations to protect the electrical integrity of your design.
Tip💡: Enable all layers in your visibility settings. Overlaps sometimes occur between nets on different layers and can be easy to miss.
“Why is Flux saying I have conflicting fills?”
Flux automatically adds GND fills to each layer, but if more than one net is assigned a fill on the same layer, it creates a conflict. The system prevents this to ensure clean and predictable copper behavior.
Only one net should apply fills per layer—typically GND, unless you're working on advanced designs requiring power planes or split fills.
“What is floating copper, and why is it an error?”
Floating copper refers to any copper (usually a fill or trace) that is no longer electrically connected to its assigned net. This often happens when components are moved or deleted, leaving behind orphaned copper.
Keeping copper grounded and connected ensures electrical correctness and helps avoid manufacturing issues down the line.
“My board has no visible GND fills—what’s wrong?”
By default, Flux adds ground fills to all PCB layers for the GND net. If you’re not seeing them, it’s usually a configuration or visibility issue rather than a bug.
Fills play a crucial role in EMI reduction, return path continuity, and thermal performance, so it's important to verify they're in place.
“I created a part, but I can’t find it in my library—where is it?”
When you create a custom part in Flux, it lives in a separate project until you publish it. Publishing is what makes it available in your global or team library.
🔒 By default, newly created parts are private.
If you want others to use it, click “Share” and set visibility permissions. Just remember to re-publish after updating sharing settings.
“I imported my Altium file, but nothing shows up.”
This usually comes down to format. Flux only supports ASCII format when importing from Altium Designer. If you export in binary format, the import will silently fail or appear blank.
To verify: open the file in a text editor. If it’s human-readable, it’s ASCII. If it’s gibberish, it’s binary.
Large schematics? Try breaking them into modules for smoother imports.
“Why is Auto-Layout stuck on ‘Optimizing’?”
Flux’s Auto-Layout feature can take time—especially on complex boards. The “Working” state may appear stuck if DRCs are unresolved, or if the board has high routing complexity.
If needed, hit Stop to investigate and restart. Just be aware that stopping clears progress if changes haven’t been applied.
“I imported a KiCAD part—why is it incomplete?”
Flux supports KiCAD library imports, but some metadata—like footprints or 3D models—need to be linked manually.
Once set, the part will behave like any other in your library.
“Why is Copilot making strange connections?”
Flux Copilot is optimized for specific, context-aware actions. It’s not intended to auto-wire an entire schematic in one go, and complex instructions often reduce its accuracy.
With more focused prompts, Copilot becomes a powerful assistant rather than a source of confusion.
“Where can I go when I need support fast?”
We want you to feel confident using Flux, even when things aren’t going smoothly. Here's how to get help:
Building with Flux means working with one of the most forward-moving platforms in EDA—but we also know that speed comes with bumps along the way. This guide is here to help you smooth them out and keep shipping.
Most importantly, you’re not alone. Whether it’s a UI quirk, a Copilot misfire, or just needing a second pair of eyes, we’re here to help—through docs, videos, chat, or Slack.
And if something isn’t working the way you expect, let us know. The fastest way we improve Flux is with your feedback.
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