July 12, 2026
Description
This project is a 3D-printed mounting system for the Robotobi's VAWT (Ø133mm). It serves as the base for my vertical-axis wind turbine (VAWT) on my balcony.
For details on the VAWT, see: Robotobi - Vertical Axis Wind Turbine VAWT Ø133mm
The upper bearing is protected from direct rain by the top cap. The lower 608 bearing, however, is not protected; the design of the lower mount does not allow for a cap that reliably prevents water ingress. I currently don’t have a better solution for this. If I come up with one, I’ll post it here. However, I don’t believe a 100% waterproof solution is feasible, so the lower bearing will likely wear out over time.
Print Settings (varies by part)
Layer height: 0.2–0.3 mm (0.4 mm nozzle)
Perimeters: 3–5
Infill: 10–20% gyroid
Solid layers: 3 top and 3 bottom
Supports: Top-Cap = yes, rest = no
Material: PLA/PLA+
Bill of Materials (BOM)
3D-printed parts (Robotobi model):
3x Wing_133mm_4X.stl
1x Upper_support.stl
2x Center_support.stl
1x Lower_support.stl
Additional parts:
1x Rod, 22.5 mm x 1000 mm
1x M8 threaded rod, 500 mm
2x M8 nuts, Nylock/self-locking
2x M8 washers
2x M8 spring washers
2x 608 bearings
3x M4x40 screws
3x M4 nuts
6x M4 washers
Findings & Observations
Vibration & Noise: If the VAWT is mounted to something metallic (like my large balcony railing), good mechanical decoupling/damping is essential. Otherwise, vibrations from the VAWT are transmitted to the metal railing, acting like a strong acoustic amplifier.
Bearing Tension: The M8 nuts must not be overtightened, as this can cause the system to bind and only rotate in stronger winds. However, they also must not be too loose, as this can lead to a knocking noise in moderate winds (at least in my case; the cause is still unclear).
Pigeon Deterrent: Unfortunately, it does not deter pigeons!
Material Durability: The VAWT + Mounting is currently made from PLA/PLA+. These materials are not permanently weather- or UV-resistant, but for my initial test, this is sufficient. Prior to this VAWT, I had a smaller wind turbine made from PLA+ for over a year. It also withstood several moderate storms without issues.
Notes & Recommendations
This design is a working prototype and not yet final. The main issues to address are the binding bearings and the knocking noises, which will require a redesign of the bearing assembly.
You should decide for yourself whether to disassemble your VAWT during storms or extreme weather conditions. Also, verify the load-bearing capacity of the structure to which you attach your VAWT.
Happy Printing
License:
Creative Commons — Attribution — Noncommercial — Share Alike