40mm to 30mm drop-in fan adapter

thingiverse

A versatile adapter designed to accommodate a 30mm fan in place of a standard 40mm fan, perfect for use in applications such as the Prusa extruder assembly. This adapter is particularly useful when you have broken all your 40mm fans and need a reliable substitute. The adapter securely holds the 30mm fan in place using the same screws that normally secure the 40mm fan to its mounting location. Update 1: To ensure seamless compatibility, I increased the diameter of the M3 holes from their original size to 4mm. This modification guarantees a snug fit and prevents any potential issues with assembly. Additionally, I incorporated a cutout specifically for the wiring of the 30mm fan. This thoughtful design feature simplifies the installation process and reduces the risk of damage to the delicate fan wiring. Furthermore, I designed an optional 10mm variant that eliminates the funnel altogether while still securely press-fitting a 30mm fan in place.