FT Viggen Bi-Directional Thrust Vectoring Nozzle

thingiverse

Decided I'd like to make a thrust vectoring nozzle for an FT Viggen I was building, so I designed this and it came out quite well. Cannot be installed after the plane is finished, unless you want to cut holes in the wing and sides. You will need: 2x 9g servos 2x linkages, preferably with linkage stoppers 1x of each section 4x of the pins 4x screws to complete the pins, but you could make a simple 3d printed pin to glue in place of the screws if you don't feel comfortable with the screws. First step that differentiates from the normal build guide is right before you put the wing on. You will need to glue one of your servos to the wall of the fuselage on the inside, with room to clear the thrust tube. This servo will exit the rear of the fuselage and control the nozzle's yaw axis. The next time you do something different, you will need to enlarge the space in the back of the aircraft's "spine" which runs along the top of the fuselage and contains all of the wiring. The nozzle's pitch servo will sit here, so cut space for the servo arm to move accordingly. Depending on the size of your servo, you may need to cut a small notch out of the back of the vertical stabilizer. I recommend bending a simple Z-bend into your pushrod to be put into the servo arms, as they will be inside the plane and inaccessible after assembly. (Before putting the wing and spine on you will need to route the servo cables up to the rx) Once you have the two pushrods exiting from small slits in their respective foam walls, you'll want to assemble the nozzle. The idea here is that the screws/nails/whatever you want to use keep the pins from moving back and forth, and the pins can be glued to the insides of the tube. The pins are already adjusted for typical expansion during print, so theres no need to shrink them. Ideally, there will be no play in terms of the sections shifting along the pin/rotation axis, so make sure you tighten the pins/screws/nails on both sides equally until there is a ~.75-1.5mm gap between the sections all the way around. Repeat this process with the pitch axis, and then I would recommend using sand paper on the base of the first section, especially if you use a glass bed, and then just hot glue/epoxy it to the back(making sure it is at correct angles and lines up with the thrust tube and control linkages). Now just program your radio, I would recommend setting a three position switch to the nozzle. On my setup it goes as so: 1. Disabled 2. Yaw only 3. Yaw and Pitch PDF file is the setup on my 9xr pro. Note: This was designed for the 70mm fan version of the standard viggen. You may encounter power issues and weight issues with the 64mm version, but I can't be sure. You will need to put your battery *all* the way forwards to account for the increased tail weight. Have fun, and happy landings!