Impossible Duct & Mechanism V2

thingiverse

5" Duct / Mechanism for use with Tricopter-Mini or Bicopter tail assembly. Mechanism can tilt upwards of 40 degrees without touching the Servo. 5" Ducts require 6" arms to maintain proper clearance. Servo users need Impossible Tail Mechanism Servo Holder "Tall" and Back Support. Note: Also suitable for Quadcopter use, making it a Mega-Whoop. ***Original Project (Old Files)*** https://www.thingiverse.com/thing:3028330 ***See the following website for more details*** https://rcexplorer.se/forums/topic/impossible-tail-duct-wip/ *** V2 Major Changes *** * Updated Propellers area of rotation, giving it a better "sweet spot". * Added version with secondary Aero Lip to utilize thrust from Propeller and draw in air mass. (Experimental & untested) * Fixed several join errors. * Added identical file without secondary Aero Lip. *** 8-5-2018 Update *** * Updated screw hole placement. * Created simpler duct without Primary or Secondary Aero Lip. *** 8-8-2018 Update *** * Added hex tool access hole to Simple Duct. *** 9-14-2018 Update *** * Added Beefier Version of Simple Duct. ***Step by Step tips for safety, ease of use and greater efficiency*** ***Note*** This assumes good print quality and no design alterations. Use 5" Bullnose Tri-blade Propellers with largest surface area to contact Duct wall. 1) When mounting the Duct, first install Propeller onto Motor. (DAL T5044 Props ideal) 2) Install Motor wires through Duct side hole (left or right) before soldering them to an ESC. 3) Mount Motor on Duct but leave screws finger tight. (Don't use lock tight) 4) Shim props using pieces of cardboard or thick paper exactly 0.5 mm thick (verify with micrometer). Be aware that cardboard gives a little, so odds are the Propellers end up closer to 0.3 or 0.4 mm. 5) Tighten down Motor screws in cross pattern to ensure even Propeller spacing. 6) Remove shims. 7) Spin Propeller by hand to ensure clearance <1 mm from Duct wall at all points of rotation. 8) Power up Motor and slowly increase speed while checking for contact. (Be careful) If they do contact the wall, STOP immediately! Afterwards sand down Duct wall or re-shim props to adjust position and repeat test. 9) Verify Propeller spacing before flight by spinning them by hand. It's possible (but rare) for mounts to shift during transport or hard landing. Trust me, you don't want Propellers contacting Duct mid-flight. *** Here's a perfect video on how NOT to setup a duct *** www.youtube.com/watch?v=mY8ZPB0Gs2I *** Bench Test of "Simple Duct" *** https://www.youtube.com/watch?v=KYfMw9gPbCE *** Test flight *** Disclaimer: this copter is largely untuned, so wind is making it hard to keep copter in front of camera. https://www.youtube.com/watch?v=rvPskyMfO-w