Minimum Air Compressor

What would be the minimum air compressor to run normal shop tools. DA sander for example. I have a 100psi 2 gallon and I think it's too weak.

Thanks FABO

Yes, what you have is way too small. I run a 5hp two stage cast iron pump belt drive compressor on a 20 gallon tank and it doesn't keep up with running a DA nonstop. It will keep up with air ratchets and impacts well. Pair what I have up with another 60 gallon tank and it would do the job.