Aircraft instrument hole reducer adapter

thingiverse

In general aviation aircraft, round instruments mounted in cockpit panels are typically one of two common sizes: 2-1/4" (57mm) and 3-1/8" (80mm). MS33638 This adapter plate enables pilots to use a 2-1/4" instrument in an aircraft panel hole designed for a 3-1/8" instrument. The design allows the adapter's surface to sit flush with the surrounding panel, but the actual 2-1/4" instrument will be slightly recessed behind the inner cutout. Traditionally purchased adapters of this style often have an inner overhang to allow the 2-1/4" instrument to sit closer to the adapter's face. However, incorporating this feature would make printing more difficult. Print Settings Notes: It is recommended to print using ABS (not PLA) because cockpit environments can be extremely hot and affect PLA strength and shape. Post-Printing Mount using MS35214-27 6-32 Instrument mounting screws or equivalent. You may need to use instrument mounting nuts A8943-632-493 Tinnerman nuts or 6-32 machine nuts if the screw fit is not secure enough.