It’s probably not a plumbed connection that’s leaking. Check the regulator or pressure switch. You can also check for leaks at the drain. If you’re leaking that much air, I’m surprised that you can’t hear exactly where the leak is coming from.
Real Mechanic’s Time Saver Magnacaddy style socket holders for about ten dollars a piece. The packaging says Torin but the product says MTS (and Torin). They have 1/4 and 3/8 in red only.
B009672BIW
B009672BQ4
If you really need to seal a connection and nothing else will work, Loctite 55 is the best option. It’s a cord sealant, and can seal straight threads without the need for a rubber washer. You see straight threaded fittings like this on some European showers, and it allows you to adjust the depth...
I'm not sure if tarnish is the right word, but I am restoring an old deli slicer (Hobart 1612), and I have a never ending black residue caused by the abrasives that I used that I can't seem to fully clean off the aluminum chassis. I used Scotch-brite discs on a buffer/polisher at around 3,000...