This is my fire gauntlet. With about 2 weeks of planning and 1 week of building I produced this. Schematics and code are available by clicking "View on Google Drive" above.
The entire assembly is mounted to my arm using galvanized steel. This steel was hand cut using heavy duty sheers and shaped to fit my forearm. The different pieces used for this were then riveted together with pop rivets. A small amount of velcro was used for the base of my forearm because it was a little loose otherwise
The gas is ran from the propane tank to a modified propane torch that I added fittings to to make compatible with 1/4" tubing. This tubing runs down my arm to an L shaped fitting and out a nozzle. I couldn't find a nozzle with the correct diameter opening so I took a cap with the same threads as the L-shaped piece and drilled a 3/32" hole into that. It seems to give me the best pressure to gas release ratio.
For the systems electronics I soldered to a protoboard an ATtiny84 microcontroller and a flex sensor. This flex sensor goes from the base of my wrist to my palm and its resistance changes depending how much it is bent against the black lines. The microcontroller then interprets this change in resistance and maps it to a servo mounted on the valve that came stock with the torch I modified. For ignition I used an arc generator to create the spark at my palm. It is essentially a large transformer that steps up my 5V input.
You can find the sketch as well as other details in my schematics provided at the top of this page.