The amazing folks at Labinnak & Mangoloo Cosplays created this fantastically detailed writeup of how to make the Robot Arm Rhys sports in Borderlands!
How to Make Rhys Robotic Arm (thing)
Edward Elric’s Northern Automail
A tutorial covering the process of creating Automail from Full Metal Alchemist.
Automail Build – Video
Building Automail? Fawnina shared the full build of her Lan Fan automail, which can be easily modified to apply to other characters and similar mechanical arms and legs.