23DT (2.3" Ducted Thing) for babyhawk gear

This is a 'true duct' frame for Emax BabyHawk flight gear (only) that offsets its weight with the thrust/efficiency gain inherent to ducted propellers. Version 1 has already been built and tested, and this is V2. This frame is printed in hollow single walls with expanding polyurethane foam injected post-printing for great strength. RCG thread is here: https://www.rcgroups.com/forums/showthread.php?2971472-23DT-the-3d-printed-Micro-130-with-true-ducts-Emax-BabyHawk-Gear

This version is sti