F 450 arms for lightness

thingiverse

After a major crash, I decided to make some key modifications to my F-450 clone with the goal of achieving even more lightness from its frame. This is just one part of a larger upgrade plan that's still in progress... One of the heaviest components is each of the four arms. With a naked weight of 52 grams per arm, that adds up to 208 grams for all four. I designed mine with the aim of using Brico aluminum pipes with a 10mm outer diameter and a thickness of 1mm, all with the same length (161mm). The final result is a naked weight of around 102.8 grams for all four arms - roughly half of the original weight. In my design, each aluminum pipe has a 3mm hole drilled out for the screw. If you want to save even more weight, you can use epoxy glue to attach the parts together. I've seen other designs that use 16mm OD pipes, but in my experience, 10mm is the best compromise between weight and stiffness. When designing each hole, I made sure to account for ABS shrinkage - for example, a 10mm hole in an STL file will actually measure about 10.4mm. Be sure to use metric screws.