If the tool air consumption ratings are close to or slightly over the compressor output ratings, it will still work. It just means you can't nail down the handle on the sander and go non-stop.
You have to get off the trigger when you are repositioning the sander, checking how the surface is progressing, or when you hear the air motor slowing down as the tank pressure drops off. That will give the compressor a minute to catch up.
I just popped a power panel out of a stucco wall with an air chisel that "shouldn't be running" on a 2-HP 4-gallon portable - you just use it in short bursts instead of constant. Stop and sweep up the mess, and give the compressor a few minutes to cool off.
And shop carefully for your tools, check the specs. The brand-name air tools like Ingersoll-Rand cost a bit more up front, but are usually a little more frugal with your air supply - compared to some of the No-Name Harbor Fright specials, they can be a LOT more frugal. And as a bonus, they live longer under hard use, and often work better
- check the stroke length on the sanders.
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