Feedback Score: 2 reviews
Join Date: Nov 2009
Location: North Arkansas
Re: How long does CO2 last???
A 50# cylinder of CO2 will be mostly liquid, which is where you get the big volume numbers. Compressed air, on the other hand is always in a gaseous state, and therefore the volume is very low for even a large diameter cylinder. Most hobby shop air compressors have about a 20 gallon tank. Air is measured in gallons, CO2 in pounds because of it's liquid state.
With the proper regulator, and keeping the CO2 tank between 60 and 90 degrees (slows the gassing rate) you should be able to use your impact off and on for weeks. This is a really tough calculation. Here are the variables: are your hose fittings tight? Is the tool working like new, or are the rotary vanes worn to the point that the efficiency has dropped? Are you doing routine tasks, or are you breaking rusty or corroded farm machinery fasteners?
Remember, air motors are extremely inefficient in performing tasks. They eat air like it's going out of style. We use electric tools when possible, as there is no waste. Electricity is 100% efficient. Air tools are never better than 50 % effecient. You need to have electricity to compress the air, then you need the air to run the tool. Makes sense! If you are looking for portability, I would go rent a 50 pound CO2 tank and the correct regulator for 4.5 cfm. There are many different regulators for beer kegs, soft drink fountain machines, HVAC servicing to blow debris out of coils etc.
This is a tough question with no pat mathmatical answer. Sorry.