Strain-Relief PCB for Brushed Motor Tabs with 90° Bend Support

In many robotics and electronics projects, small brushed DC motors are a staple due to their simplicity and availability. However, a common issue we’ve encountered especially when working on competitive or high-vibration applications like BattleBots is the fragility of the motor’s solder tabs.

These small metal terminals are not designed to handle repeated flexing, pulling, or stress from wiring, and as a result, they often break or become unreliable after only a short period of use. This is especially problematic in compact builds where space constraints force tight bends in the wiring or when frequent disassembly and reassembly puts added strain on the motor connections.

To address this issue, I’ve designed a custom PCB that attaches directly to the motor tabs and serves both as a mechanical reinforcement and an electrical interface. The PCB sits flush against the rear of the motor and allows the motor terminals to be soldered securely onto it, distributing stress away from the tabs themselves. The traces on the board then lead to a set of repositioned output pads that allow wires or connectors to exit the motor at a clean 90-degree angle. This eliminates the need to bend wires sharply right at the fragile tabs, which is often the root cause of mechanical failure.

In addition to reducing strain, this board makes wiring more modular and cleaner, especially in builds where internal space is at a premium. The PCB design also includes optional mounting holes, making it easier to secure the board in place using zip ties, screws, or epoxy, depending on your specific application. It’s a small modification that significantly improves reliability and serviceability, particularly in environments where durability is key.

This project is particularly useful for robotics teams, hobbyists building compact mechanisms, and anyone working with brushed motors in high-impact environments. I’ve included the Gerber files, schematics, and design source files, and I welcome feedback or improvements from the community. Whether you're building a combat robot, an RC car, or a custom automation tool, this little board could save your motor and your day.