Customizable blade replacement for repairing centrifugal fans with broken blades on laptops, 3D printers, and anything else.
How to determine sizing:
- Cut all the blades off of the damaged fan leaving short (~1mm) and evenly sized stubs. Using flush cutters to do this will ensure that all the stubs are the same length.
- Measure the diameter of the rotor with blade stubs included.
- Change the hub inner diameter in the customizer to match the measured diameter in order to achieve a tight press fit. You will need to increase this slightly if your printer typically prints holes too small.
Tips:
- For best results, try to match the blade length and blade count of the original fan.
- Use the most rigid material you can (PLA is a very good choice, followed by glass fiber or carbon fiber filled materials).
- The blades should be as thin as possible while still being rigid for the highest efficiency. 0.8mm thick blades work well with PLA. I tested a 54mm diameter PLA impeller with 0.8mm thick blades and it exploded at around 19000 RPM. The vast majority of standard centrifugal fans run well below this speed.
- Balancing should not be an issue for general-purpose use based on my experience.
How I Designed This
I originally designed this in Fusion 360 for fixing a dropped laptop with broken fan blades, and created a simpler version in OpenSCAD to publish on Thingiverse. The Fusion 360 file is included for further customization including angle and curvature of the blades.