The McGraw Long-Barrel Air Hammer, priced at $39.99, is new to Harbor Freight's air tool offerings. While it currently only has six user ratings, they're all five-stars, and it's recommended by ...

So, say the SCFM-rated tool you have is an air hammer with a 4.4 rating at 90 PSI. Multiply that figure by 1.5 and you get 6.6 SCFM, which would be the minimum a compressor would need to provide ...