I do have a pretty large sandblasting cabinet and before I picked it up I kept reading people on form saying that you can never really have too much compressor for that. And besides that I figured just always go as biggest possible
A large sandblasting cabinet will even tax the 7.5HP 80 Gallon T30 that you are thinking of buying for $1K.
What pump model does it have? It looks like a 2475. The tag on the pump crankcase will have this info.
It is hard to tell from photos of the pump itself if it is a 2545 or a 2475.
What is the brand on the electric motor? The rounded top capacitor housing makes it look like it could be a Baldor?
Around the time when Ingersoll Rand switched to tan colored paint about 27 years ago, they also changed their suppliers for electric motors. 25 years ago, the single phase 7.5 HP motors that IR used were made by W.E.G., and had a large flat top capacitor housing.
Based on the gray paint color of the T30 that you are looking at, I would estimate its age to be at least 30 years old now.
The unit in the photo does not appear to be a "fully packaged" model, so it does not likely have an auto drain.
The biggest risk in buying a used air compressor is neither the pump (a 2475 is rebuildable) nor the motor (blown capacitors are replaceable). Rather, the risk is in the tank.
When I bought my 80 gallon 7.5HP IR T-30, I took off the pump and the motor (each required a shop crane to lift them off individually... I couldn't even lift the electric motor by itself). I then took the tank to an oil refinery inspection outfit for them to run an ultrasonic thickness tester on the bottom bell of the tank, and compared their findings with the National Board Registration Label shell and bell specifications welded on to the tank when manufactured. It was within spec.
I then filled the tank with water, attached a pressure gauge, and pressure tested it with a grease gun filled with water, to 220 psi. It held.
I then attached a full bore drain port, consisting of an elbow, a one foot horizontal extension, and an easy access ball valve... no fussing around reaching under the tank to fool with petcocks. I also bought a Wilkerson automatic drainvalve.
New, an 7.5HP (true running, not peak) single phase 80 gallon Ingersoll Rand branded compressor ranges between $3,600.00 to $4,500.00, depending on whether fully packaged or not.
Ingersoll Rand offered the 2545 pump with a single phase 7.5HP motor for only one brief period of time that I am aware of, which was one of their anniversary editions. Otherwise, the 2545 pump is normally paired with a 10HP motor, which is not available in single phase. The 2475 pump is more easily driven by a 7.5 HP motor, which is the maximum HP motor available in single phase. That combination puts out 25 CFM at 90 psi, more or less.
It is the CFM that you need to run a large media blast cabinet.
You will be hard pressed to find what you found for less than what you negotiated.
