Landing gear adapter 16mm tube

Directly i do this design for fix where i like under my Spyda 500 Hexacopter.For use whit carbone tube 16mm,put some oil or similar for inside the tube.He have 30 angle degrees ,i think is the good angle.Finally im not using this landing gear type because is to heavy for my hexa but he work.Obviously need more stl for fix whit the horizontal tube. Do it whit Freecad