Cfm ratings based on compressor?
 

I've done quite a bit of spraying using my friends 10 gallon 1.5hp air compressor and Costco paint gun, and I've gotten surprisingly good results at about 50psi.

So I've been shopping around for a compressor for myself. I was looking at a few 2 hp compressors, which put out about 6cfm at 40psi. I saw a compressor size selection chart, and saw that 10cfm is recommended for HVLP guns. Which is surprising because the one I've been using probably puts out 4cfm and worked fine.

It seems to me that an air tank would flow whatever is asked of it, so are cfm ratings based on what the compressor can supply once the tank starts to drain? Meaning, will a 20 gallon tank rated at 6 cfm actually put out 10cfm or whatever you need? Is it just the compressor that won't be able to keep up? (Putting out only the rated 6cfm)

Thats usually how it works, the pump that operates the compressor does'nt have the balls to compress the tank that much. Look around for compressors from shops that go out of business, you'll pay the same as a new one but you'll get a real compressor that does what its supposed to.

I love my HF 60 gallon compressor its 2hp 15 cfm @90 psi, But i'm building a stupid air system right now 2 compressors (both about 15 cfm @90 psi) with 3 60 gallon tanks. Plus im going to get a condenser this weekend from a junk yard to help better dry my air.

The tanks is just a reservoir It will supply what ever pressure/CFM. The lower CFM compressor will result in longer cycles to keep the tank pressurized and it may not be able to maintain pressure during heavy use. The reality is that you are not constantly spraying. Therefore a lower CFM compressor will do fine.

Ya, that's sort of what I was thinking. Guys on the autobody forum are claiming that you need an 80 gallon 5 hp compressor setup minimum. But I've been doing ok with just a 10 gallon.

Just bought a Snap On 20 gallon off of ebay. Guy, ya I'd like to have an 80 gallon, but I want to be able to transport it.

Let me know and we'll toss it in the truck.

Lol, appreciate the offer man