The core of the flamethrower mechanism is a a bottle of WD-40 that sprays oil at a lit candle/lighter and acts like a flamethrower. This project is a good combination of rapid prototyping + some basic power electronics.
This project was a joint project with Victor Rodriguez and Candace Chen.
Step 1: Get the materials!
1. WD-40 Can
A can of WD-40 (get a 12oz can) This should be readily available at your nearby hardware store.
Get a "door-lock actuator", these are linear actuators that sometimes are put on cars to automate the door locking mechanism (they press the button down for you when you hit a button on the driver side). These should be available from Amazon or Ebay, here is an example:
Anything that looks like the above should be fine (they normally run on 12V because that is what the low voltage system of a car runs at).
3. Some hot glue and hot glue sticks (any should work)
4. A piece of hanger wire or welding rod.
5. RC Car from Radioshack
Buy the cheapest RC car from Radioshack (should be about 15 bucks or less)
6. A n-channel mosfet and a diode and a 1k Resistor (these from sparkfun should be fine but you can probably use any power FET + diode you have laying around)
https://www.sparkfun.com/products/10969 (you can probably use any value between 500-10k Ohm so don't feel obliged to buy a pack of resistors.
7. Cardboard, or Acrylic or Sheet metal, anything to make your box enclosure
I used acrylic to laser cut a box for the assembly but you can use anything you want.
8. Tape and/or Acrylic Cement
To fasten your box together.
9.Solder Board or Bread Board
10. Quick-disconnect or any kind of connectors
11. AA Batteries + Battery Holder
12. Candle and a lighter