Thanks guys.
Yea TJ I remembered your build. I looked it up on cx today but the pictures didn't load.
I was looking at an 11 gallon tank would that be sufficient?
If not I could get a cordless impact and just have it run the lockers and be done with it.
Sent from my iPhone using Tapatalk
LOL
I don't know what it is with the pics on that...its like they work for a year, then don't, then do....and I am not changing anything...very random....even for some it always works, for some, never....all very weird.
If you get an electric (Li-ion, etc) gun, etc, sure, you have a Plan B for tools, and those work great.
11 gal is a good size, but, harder to find room to fit other than using up interior space. You CAN use multiple smaller tanks too. People have used their sliders as tanks for example, you can be creative.
Lockers use fairly low PSI, filling tires uses unlimited for speed/resetting blown beads, train horns use ~ 150 psi, and most air tools are limited to ~ 90 psi or so. Different tools use different CFM though as minimums.
The main thing about using a tank are regulator(s) for the item that DON'T use full blast air, such as lockers and air tools, etc...so you don't blow them up, etc.
The more PSI a tank can hold, the "more air" you can stuff in there.
For example, if you need to air tires back up to 40 psi, when the tank has 40 psi in it, it may only put ~ 20 psi in the tire, as it may get split 20/20 when it equalizes. It might need closer to 90 psi to start, to fill a tire to 40 psi...depending on the volume of the tire, and the tank.
Some tanks are only rated to hold 120 psi or so...so, that doesn't store as much air as a tank rated at 150 psi, or, one rate at 200 psi, etc.
Of course, the COMPRESSOR has to be able to pressurize the air in the tank to those limits to take advantage of it.
Once a LARGE tank is drained, the compressor needs a LONGER time to fill it again/Re-pressurize it again to a high pressure.
That mostly means that once drained, you are filling tires from the compressor rather than the tank per se.
An average 33 x 12.5/15 holds ~ 3.5 cubic foot of air IIRC....but you need another complete volume to add another ~ 14.7 psi to a tire (They start at ~ 14.7 psi because that's atmospheric pressure).
So, to round it off, lets say you aired down to 15 psi, there's really 15 psi plus the 15 psi for the atmosphere....so to get to ~ 30 psi, you need to add about 3.5 cubic feet of air...or about 26 gallons.
If the tank is 26 gallons, it would then need to simply have enough psi to force the tire to increase by ~ 15 psi, so the tank's ENDING psi would be no lower than 30 psi (Equalized). That would be ~ 60 psi to start with for that 26 gal tank.
If the tank is 13 gal (Half the 26 gal), the starting psi psi would need to be doubled, to ~ 120 psi, to get the same end volume/psi into the tire.
If the tank is 6.5 gal, you now need it to start at closer to 240 psi to get the same end result, and so forth.
Of course, with a compressor filling the TANK from the other end, the entire time air is leaving the tank to go to the tire, the compressor is adding air to re-fill the tank....so you can play catch up.
Most compressors for truck tires are rated at their CFM at ZERO PSI...but, in reality, the CFM drops sharply as the PSI increases. For tank filling, if its a 150 psi rated tank, you want to know how well the compressor can fill once the PSI gets to say 100 psi or more, and that number is typically ~ 1/2 the rating at 0 psi.
Some do list their output for psi higher than zero, with 90 psi (An air tool target) being an example....that number is closer to what cfm the tank is going to be filled at.
So, if your compressor can do 3 cfm at 90 psi, that's almost a tire volume per minute (If we use the ~ 3.5 CF for tire volume)...so, if it takes the tank about a minute to fill the first tire (To 30 psi from 15 psi), by the time that minute is over, the compressor has replaced much of the air already....so you can start tire #2, and so forth...or have enough capacity left to take tire #1 from 30 to 45 psi, etc.
In practice with the extremeair and a 4.5 gal tank, it took ~ 45 seconds to air up the 1st tire, and a few minutes for each after that...unless I do one, then go do something else for a bit (While its recharging...), then do another in ~ 45 seconds, and so forth.
If using it to spin on lug nuts, no problem, as there's a pause between each nut, etc...and that's enough recovery time. You could not run a grinder, etc, continuously though....as the 90 psi would not be able to be maintained if using over ~ 3 cfm.
The absolute fastest tire filler etc would be a CO2 tank though, unless you got an OASIS, etc...which is pretty much a 45 lb DC shop compressor you mount in your rig.
