Overview

This is a mini retro-styled desk fan that has a functional oscillation mechanism. The design is a complete rework of my older oscillating fan model.

It uses a common 130 size brushed hobby motor and incorporates an 18650 battery in its base for completely portable operation. Compared to the older design, the new version has significant internal changes, resulting in much quieter operation and an easier assembly process.

Fusion 360 model link: https://a360.co/3g4nEfN

Changes

• All fasteners standardized to M3x10 bolts and locknuts.
• Reprofiled base to fit standard 18650 battery holders, instead of requiring a lithium pouch cell. Battery life should be much longer as a result.
• Main shaft gear is now an internal gear of a much larger diameter, with curved spokes to reduce noise transfer. Motor pinion gear has a small cutout to achieve a similar effect.
• Motor/shaft drive gears now have larger teeth, requiring less precise clearances.
• Motor mount redesigned to allow adjusting gear clearance. Attachment points have been thinned out to reduce noise, with a TPU-specific variant available for even lower noise levels.
• Redesigned blade assembly with individually adjustable fan blades. Blades are much wider and have greater camber, reducing noise and moving more air. Subjectively, they look a lot better too.
• Front housing extended rearwards, with motor mount attaching directly to it instead of being sandwiched between front/rear shells. Allows opening up the housing without the motor mount coming out.
• Rear housing bolts are now exposed on the outside of the housing, instead of being hidden inside, for much easier housing assembly.
• Added a springy cutout at the bottom of the loop/handle component to reduce noise transferred to the base.

Recommended filaments

• Standard PLA/PETG/ABS for the main body parts and oscillator gearbox
  • Important note: certain filaments have much more friction than others, such as the Prusament Galaxy Silver I used for the exterior parts. In this case you'll want to print all the internal oscillator parts out of a filament with a more slippery filament.
• TPU strongly recommended for certain parts to reduce noise levels. These include the main and motor pinion gears as well as the motor mount. Optionally the mid shaft, front shaft, and oscillator screw can also be made in TPU to reduce rattles.
  • TPU-specific variants of the front shaft and motor mount are provided in the files.

Parts

• 130 size hobby motor. Try to find a low RPM motor rated for higher voltage (6V/12V). The typical 1.5/3v ones spin too fast with too little torque to work well with this design, and may overheat and burn.
  • For a good quality option, the Mabuchi FK-130SH has carbon brushes and is rated 7200RPM@12V. It runs quieter than the generic hobby motors.
• 608 bearings (x2)
• 18650 battery and holder
• Mini toggle switch with 6mm/0.25" thread diameter
• TP4056 charging board
  • A small heatsink is highly recommended - these cheap charger boards get extremely hot in certain circumstances
• Adjustable boost converter (2-24V) - highly recommended to better tune the motor speed. If your motor runs at an appropriate speed at normal battery voltage, this isn't needed.
• M3 locknuts (x25)
• M3x10mm button head bolts (x32)
• 35mm nylon standoffs (x3)
  • Printed standoffs can also be used
• Mini felt or rubber feet (x3)
• Hot glue, wires, etc.

Printing recommendations

• Print all the TPU parts individually, in particular the rotating shaft components and gears, to reduce stringing.
• Depending on your bed surface, the oscillator arm and handle will likely need a brim to keep them stuck down.
• Part clearances have been optimized for my own printer and will probably need adjusting.
• For the cleanest surface finish, I used 0.1mm layers. Anything from 0.05-0.2mm should be fine for this design.

See the Printables page for the full build guide.