Thanks for all the answers. I’m thinking about making a cocktail-making machine powered by an Arduino board, so the liquids it would be propelling range from spirits (probably wouldn’t have to worry about microbial growth there) to mixers, carbonated and non-carbonated.
In a similar post, I asked about the best way to dispense fluids and ultimately I think I came to the conclusion of just pressurizing everything instead of relying on pumps (though I’m still open to suggestions).
So how easy are nitrogen/CO2 containers to obtain? Quick searching led me to some welding supply stores and lots of paintball discussion…
Easy. I have three myself, they’re useful for airing up tires offroad. I’d check around nearby to see how easy it will be to refill them. It should be easy to find a place, but depending on your area it may be a hassle. I have to drive 15 miles to refill mine and they’re only open during the week when I’m at work and can’t do it. But they last longer than you’d expect. I’ve aired up all 4 tires from 5psi to 30psi 3-4 times with a 5lb tank that’s only slightly larger than a 2 liter soda bottle.