What brand DA?

I bought a cheap DA from harbor freight and all though it works it takes a ton of air!  I have heard the more expensive ones are more efficient on air.  If this is true which one should I buy that wont break the bank?

My air compressor is a 60 gal, 175psi, 7hp craftsman.  The HF DA pulls it down quick!

You need to look at what CFM your compressor puts out at what PSI you want to run the DA (usually around 90 PSI for a DA). then look at different DA's and their air requirements and match it up. simple as that.

CFM is dependent upon the design of the tool. Some use a lot, some use very little. Don't know what your compressor is rated at, but if a dual stage 7hp compressor has trouble keeping up with a single DA, you might be in for a rebuild soon.

by DA what tool are you talking about? I know I have a couple of 3.5 inch circle sanders from harbor freight and if I don't run them at 120+ psi they don't work for crap even on a giant dual stage IR compressor. (150 gallon I think) Seems like the harbor tools are so bad at efficiency that I need to run them at 30% over to get regular results.

edit.... sorry but I've never seen the term DA used to describe a dual action air powered sander. If this is what you're asking about then I can only assume its even worse than my 3.5"s

The DA (6"orbital palm sander) I have from harbor freight is 14cfm @ 90psi.  My compressor is rated at 9 cfm @ 90 psi.  I am no math genius but this is a bad combination right???

This sander is 6 cfm @ 90 PSI

https://www.eastwood.com/contour-pro-6in-random-orbital-sander-3-32-orbit.html

The Kobalt from Lowes is supposed to be 4.5 CFM at 90 psi.

So basically I got a junk sander from HF that my compressor is never going to keep up with????

Yes. Also 9 CFM at 90 PSI on a 7HP 60 gal compressor is not very high?

Yes. Also 9 CFM at 90 PSI on a 7HP 60 gal compressor is not very high?

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Yeah I was surprised at that too but thats what the sticker says on the tank.

Are the intake air filters on your compressor clean? It doesn't take much restriction to reduce it, further shortening your work time.

Are the intake air filters on your compressor clean? It doesn't take much restriction to reduce it, further shortening your work time.

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Yes they were  just cleaned.

When you do the math you can see why you run out of air so fast. A 60 gallon air compressor has about 8 cubic feet of air. The multiplication factor difference of compressed air between 90 psi and 175 psi is about 7. So, that gives you a starting 90 psi equivalent volume of about 56 cubic feet of air, a little over half a minute if the compressor doesn't kick on, maybe another half a minute if it does.

When you do the math you can see why you run out of air so fast. A 60 gallon air compressor has about 8 cubic feet of air. The multiplication factor difference of compressed air between 90 psi and 175 psi is about 7. So, that gives you a starting 90 psi equivalent volume of about 56 cubic feet of air, a little over half a minute if the compressor doesn't kick on, maybe another half a minute if it does.

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Yeah what Don C said!