I also have an air tank. Mine has a shut off valve as part of the inlet.
It really holds the pressure. I make a habit of always filling it to 100psi
when I'm done using it so I always have air quickly when I need it next.
Sometimes, I won't use it all winter and it never loses pressure. If I
don't use the shut off valve, it does lose pressure.
My main complaint with air tanks is one of physics. The amount of pressure
you have in the tank is only usable down to the needed pressure in whatever
you are inflating. If I'm pumping tires to 50psi, I only get to use the air
from 100psi down to 50psi. I still have 50psi in the tank, but I can't use
it (at least not for the tires). You can't change physics.
All in all, I find it very handy. I have taken it camping several times
when I know we have a tire with a slow leak.
Wally
www.vintageairstreamer.com
> I have an air tank at home. Its almost always empty when I wish for air.