3D Printed Desk Fan

I'm Hilary Choi. For Ms. Berbawy's Principle of Engineering class, I decided to make a 3D printed desk fan in the shape of a fox. Inspired by and following the instructions of dinochen1983's Air Fan.

During a hot day, a great way to cool off is by using a fan. The desk fan is battery powered with a push button switch in the front to turn it on/off. The creation of a 3D Printed Desk Fan is relatively simple, but will require much trial and error when designing parts. It is a good way to improve CAD skills and become more familiar with 3D printing. In addition, it helps one gain more experience with circuits.

Materials:

• DC Motor (2 mm axis)
• Fan Propeller with Soft Blades
• Switch
• 9V Battery Holder
• 9V Battery
• 3D Printing Filament
• Single Conductor Stranded Wire (24 AWG)
• Heat Shrink Tubing
• Solder
• Superglue

Equipment:

• 3D Printer
• Soldering Iron
• Safety Glasses (when soldering)
• CAD Software
• Slicer software
• Wire Cutter
• Wire Stripper
• Dial Calipers

I started creating the desk fan by drawing a basic design. The final product differed a bit from the sketch. I used sketch as reference when designing parts.

I used Fusion 360 to model the DC motor, switch, and battery holder. When needed, I used dial calipers to take appropriate measurements so that my parts would be accurate.

The models did not need to be very detailed because they were used just as reference when designing parts that needed to be printed. It is very helpful to have parts like this modeled to keep the overall design accurate.

Next, I designed the parts for the body of the fan. It was important to take tolerances into account.

Here are my parts:

I created an assembly in order to ensure that the parts would fit together. I had to make several changes to each part file. If I had not made the assembly, I would not have known to redesign until after 3D printing, which would have wasted time and resources.

I converted my part files into STLs. Then, sliced and a 3D printed them. For this, I used Prusa Slicer and a Prusa Mini 3D printer.

I printed two eyes, one head, one tail, one body, and one base. Eyes, head, and tail required supports. I used pearl red PLA filament for the head, body and tail, galaxy black for the base, and glossy black for the eyes.

After the parts were printed, I fitted them together. Some didn't quite fit, even after I had double checked them in the assembly, so I made some adjustments and reprinted some parts.

I used dinochen1983's circuit map from the Air Fan tutorial. The circuit map is used for reference when creating the circuit and soldering.

Before soldering, I cleaned the work area and adorned safety glasses. Clamps or help from another person were needed in order to keep the wires stable.

I used wire cutters to cut off two 4-5 inch long portions of wire. Then, I used the wire strippers to remove approximately 1/2 inch of the insulation.

I slid 1/2 inch of heat shrink tubing onto the wires prior to soldering the wires together. In addition, I placed heat shrink tubing on the prongs of the switch. Because I didn't have a heat gun, I used the soldering iron to shrink the tubing by putting the tip of the soldering iron close to (but not touching) the tubing around the wire.

After cleaning the exposed wires, they were soldered to the switch. When finished, the switch was secured to the body.

I placed the battery holder in the base and popped the wires through the small hole in the bottom.

The wires were soldered together: the battery holder's black wire to one of the switch's wires.

It was imperative to treat the DC motor gently, else the wires would break off. Positive was soldered to positive and negative to negative.

I tuned the wires into the body of the fox and the fan was finally assembled. The DC motor and the snout was a tight fit. I used superglue to glue the eyes onto the head. The head was glued to the body and the body to the base. The tail was glued to the body though the large hole in the back. The lid of the base was not glued, however, because I wanted to be able to access the electronics. Lastly, the DC motor was glued to the snout. When the glue dried, fan blades were popped onto the shaft of the DC motor.

I left the switch on the battery holder in the on-position so that when the push button is activated, the fan turns on. The fan now works!

Many thanks to Ms. Berbawy for making this project possible and dinochen1983 for the inspiration. I would also like to thank Ms. Berbawy, my classmates, friends, and family for supporting and helping me when needed.