For those venturing into 3D printing gears, I've found that experimenting with different filament materials can dramatically affect the strength and durability of the final gear. For example, using PETG or Nylon instead of standard PLA can provide better resistance to wear and heat, making the gears more suitable for functional transmissions. Additionally, design plays a huge role. When I started creating gears, I learned that ensuring precise tooth profiles and adding a slight clearance between mating gears helps reduce friction and wear. Software tools that allow precise control over gear parameters, such as number of teeth and module, are invaluable. Another tip is post-processing your 3D printed gears. Light sanding and applying lubrication can extend the life and improve performance. For transmission applications especially, testing the mechanical limits of your printed gears under load before final assembly can save time and material. Lastly, joining 3D printing communities focused on gears and transmissions offers great insights and shared designs, which can accelerate your learning curve. Embracing these approaches has definitely enhanced my 3D printing projects involving gears, allowing for more reliable and creative outcomes.