Bearing the mantle of the Titan of the Sun, the 'Helios' was designed with a singular vision: to provide a platform for an ultra-lightweight high thrust-to-weight ratio 3.5" DJI O3 FPV build. Harnessing the divine spirit of its namesake, the build is destined to carve paths through the skies, bridging the mortal world and the heavens in its flight.

Build/Design/Test Video:

To get the Carbon Fiber frame cut (and all needed hardware provided if desired): https://www.cncdrones.com/recursion-helios-35-ultra-light-frame.html

Naked TPU Armored Housing

There are two files available for print. One is “UNCUT”, and the other is cut. This means once you've removed the DJI O3 camera from the stock metal housing, you can put it directly into the housing as is (uncut), or cut away unneeded plastic used for mounting the camera in the metal case to save weight (about 0.2 - 0.3g).

This should be printed with the back of the housing facing the build plate. Support should only be needed where the base and the circle housing meets, which is minimal. Be sure to remove any stringing if it occurs inside of the housing to ensure the camera can slide in, as it is designed to be pressure fit inside to secure it. You may add a tiny amount of hot snot (glue) if you want additional security at the edges of the camera at the back of the housing, but this shouldn't be needed.

Recommended Build:

- Panasonic Low ESR 25VDC 470uf Capacitor - Mfr: EEU-FR1E471Y
- Motors: T-Motor F1404 3800Kv (supports any motor with 9mm mounting holes)
- Propellers: HQProp T3.5x2.5x3
- Flight Controller: 20x20 or 25.5x25.5 AIO, with a 9.5mm maximum clearance between the center of the 20x20 mount hole and the stand-offs.
- Battery: 4s 550mah Tattu or equivalent low internal resistance high quality lipo or greater. A larger battery may be required if you don’t go with the recommended motor/propeller combination.
- Video: DJI O3 System, Stock or Naked (Required)
- 60mm DJI O3 Camera cable (Stock cable will work)
- 10x130mm Battery Strap (For 4s 550mah. Longer for larger)
- 2 x 5.8GHz Whip Antennas (only if not using the DJI Remote Controller)

Spacers

I have also uploaded the m1.6x5mm spacers I used for the Naked O3 airunit. These were made to be as thin and light as possible, so for them to work you'll need to print with the smallest layer height you can get away with with arcane walls. If this doesn't work for your printer, you'll need to make some thicker ones. Reach out if you're stuck.

Nuts

Same commentary as above. These can be used to screw in flight controllers/Naked O3 into the stack. Do not use on the carbon side as metal is important there for increased stability and durability.