Fabrication Week 1: Building a Flashlight


The Assignment: to build a flashlight

The Requirements: Portable, creates light.






Initial Plans:


Materials required (I think...)

  • Plastic soda or water bottle

  • D2 Batteries

  • Copper tape or wire

  • Lightbulb (I used a 1.5 flashlight lightbulb)

  • Aluminum foil


  • Scissors/Exacto knife

  • Electrical tape

  • Wire stripper


Attempt #1:


Issues with attempt #1:

  • The insulated copper wire is very inflexible-- it's hard to connect the lightbulb and negative side of the battery to the cable. Definitely needed a thinner wire.

  • The D2 batteries are too large to be conveniently connected to the lightbulb (which is comparatively tiny.)

  • The body of the soda bottle ended up being much too wide to effectively house the batteries/wire/light circuit.

Attempt #2

This time I tried with smaller batteries (AA) and copper tape. I secured the AA batteries to one another with electrical tape, lined the top of the soda bottle with aluminum foil for reflectivity, and secured the copper tape to the negative side of the bottom battery and to the side of the lightbulb. I then put the lightbulb through the cap hole in the top of the soda bottle and added more aluminum foil to keep the lightbulb in place. I also wrapped the batteries in cardboard and black masking tape to make it easier to grip (you can see this in the first video.)  


Proof that it works/worked. It requires pressing the bulb into the top positive side of the battery, but lights up pretty well. 

What would I do differently?

The one major change I would make to this flashlight design would be to put some copper wire between the bottom of the lightbulb and the positive terminal of the top battery to create a more reliable connection between them. Then, ideally, a user could turn the flashlight on and off by un-taping the copper tape/wire from the bottom of the flashlight, which seems safer (e.g. no risk of breaking the very thin glass or burning oneself on the lightbulb when pressed for too long.)

ITP, FabricationCaroline Neel