This is an old, but good, project that I built a few years ago. I retrofitted a commercial fire extinguisher to hold and dispense beer. I brew my own beer at home, so it is fitting to have a homemade "keg" to hold homemade beer!
The extinguisher tank is stainless steel, and fairly easy to clean. The top unscrews, and leaves a 3" dia hole. The extinguisher was originally setup to dispense fluid (ie it has a downtube that connects the outlet to the bottom area of the tank, and a port on the top for adding pressurized gas). This is exactly what we want to dispense beer. The main modifications that I made were:
Replacing the original (nasty) downtube with a new clean one
Replacing all of the rubber seals with new ones
Lots of cleaning
Added a low pressure gauge and compressed air quick-connect system (not shown in the photos)
I got my CO2 cylinder and regulator at a local welding supply store. It was expensive, and I am not sure if it was worth it.
In order to carbonate the freshly brewed beer, I keep the extinguisher in the refrigerator with the CO2 tank set for about 12 psi. I give the beer a vigorous shake once or twice a day, and after a few days or a week, it is ready.
The extinguisher is always a hit at parties, and has become a tradition.
- I previously worked on Virtual Reality and other hardware at Valve. I currently work at Google[x].
Prior to starting at Valve, I built computer peripherals such as keyboards, mice, and joysticks that were designed to be used inside MRI machines. My company, Mag Design and Engineering, sold these devices directly to researchers at academic institutions who used them to publish scientific papers in peer-reviewed journals.
After work, I spend time on many different types of projects that usually involve circuit design, machining, material selection, and general fabrication/hacking. My favorite place to be is my home workshop.
ben dot krasnow at gmail