Making the air raid siren
Dates:
Day 1 (Feb 15):
I found some ideas to make. My four ideas are air raid siren, water wheel, magnetic train, and rube goldberg machine.
Day 2 (Feb 17):
*Missed due to band class
At home, I decided to make a model of the turbine the air raid siren. I was about to use Fusion. However, after trying to model fusion, it was difficult for me. Therefore, I made a 3D model of it in Tinkercad.
Day 3 (Feb 21):
When I got to school, I quickly measured the pointy part of the motor, so I can ensure the motor fits the siren to make it spin correctly. Right before I 3d printed my air raid siren, I decided to change the height of the siren to 4cm because I felt if it was too small and might not create a humming sound.
While the 3D printer was printing my turbine, I began finding a base for the motor to sit in because I realized the intense shaking that the motor might make to make the siren wobble.
Day 4 (Feb 23):
Missed due to BEIMUN
*At home, I made the 3D model of the outside case of the air raid siren
Day 5 (Feb 27):
I got my 3D-printed turbine. Then, I began 3D printing the case. While printing the case, I found out my motor was gone! I can’t find it anymore! Luckily, I was able to find another motor. A circular one. The circular motor was relatively easy to make sure it didn’t shake. After talking to Mr. Michie, he decided I should drill a hole that’s the diameter of the motor. Later, I went to the fab lab, drilled a hole, and the motor fits perfectly. However, the turbine’s hole doesn’t fit the pointy part of the motor because the circular one has a plastic base, but I was able to resolve the problem by hot gluing the motor on the turbine.
After finishing drilling, I found a switch and a battery pack. Then I started to solder the wires together with the help of Bowen. Furthermore, I’ve realized that the height of the turbine case could be too short. Thus, I added two wooden planks at the sides to make the case reaches the height of the turbine.
*** On Tuesday, I found out that the 3D printing case was too small! So that night, I quickly remake a new one. The original one was 7cm*7cm, and I changed it to 8.2cm* 8.2cm
Day 6 (Mar 1):
When I first got to the school, I rushed to the design center and printed my part. Fortunately! in the afternoon, my case was printed! However, the case was a little too big, so I hot-glued some cardboard on the case. Approaching the end of the class, I hot glued the case on the siren, and… the moment of truth… IT WORKS!
I asked for some feedback from my friends:
Eddie: The air raid siren is very visually appealing. The red and white create contrast. I could hear the whistling sound from the siren, but I feel the siren could be louder, and there’s a flappy motor sound which makes it doesn’t sound as good. Overall, it’s very good
Bowen: Looks very good, but it could be louder
Andrew Luo: Looks good. I can definitely hear the siren sound but I feel it will be better if could be louder. Also, the siren has a flappy and vibration sound?
Jayden: The siren is not loud, but it looks cool
The general consensus is that my siren wasn’t loud, and it made that flappy vibration sound. I went on fixing the problem straight away. I realized the vibration sound could be coming from the motor, so I taped the motor more, and I took off the turbine case, and pealed some layers of the cardboard because the wind pushing outside could make the cardboard create a flappy sound.
Here’s my finished product!
As you can hear, most of the flappy sound is gone, and the siren is a bit louder.