I modified the T4 Quadcopter arm to have a cutout for an ESC (DJI 30AMP). The arm also has holes cutout for zip ties to be put through the arm and around the ESC. I have also added another file for pancake motors. This file has the arm motor mount raised towards the top with a little space to recess the motor mount from the motor into the arm a little. The bottom is also cut out. I've also added a hole on the motor mount side of the arm to allow for a LED to be added. I've put my Rctimer 5010-620KV motors on this arm. http://rctimer.com/product-911.html Tinker this at TinkerCAD: https://www.tinkercad.com/things/eeyW3mPFbS7-t4-quadcopter-arm-escI printed this with ABS .2 25% Fill with supports using Davinci 1.0A. Bed: 105 Extruder: 230 Since I was using ABS there is some shrinkage from the body, so I had to scale this model to 97.3% to fit in my body. This may not be an issue with others. Just something to keep in mind. I would print out a segment of the arm to test with your body before you commit with the full print.