Difference between 2 CFM & 7.5 CFM die grinder??


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Old 09-14-08, 08:35 AM
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Difference between 2 CFM & 7.5 CFM die grinder??

Besides needing more air flow, what will be the difference when using these 2 air die grinders?

Tractor supply has a Farmhand 18,000rpm/7.5 CFM (or thereabouts), whereas Lowe's has a 18,000rpm/2 CFM (or thereabouts) ... about the same price. How will these perform differently?
 
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Old 09-14-08, 10:29 AM
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Welcome to the forums!

I don't know why the big difference in cfm. Usually the better built air tools won't use as much cfm as a similiar cheaper built tool.

The more cfm you use, the harder the copressor has to work to keep up. If you use more cfm than the compressor can put out, you will end up either operating the tool at a reduced speed or waiting on the air compressor to catch up.
 
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Old 09-14-08, 11:19 AM
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2 guesses, since I can't see the complete specs on either one.

Are they being rated at the same pressure? IE 7.5@90PSI and 2@90PSI?

Could be one has larger vanes on the turbine, so may give more torque, but use more air. With a die grinder I wouldn't think that would be a huge issue, it's more about the speed of rotation.

Agree with marksr, but thats really a big difference. Normally it's more on the order of 1 or 2 CFM.
 
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Old 09-14-08, 04:10 PM
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don't believe

everything you read in Lowe's. Me thinks there is no such thing as a 2 cfm die grinder. Even a 1/4 horse one will consume about 15-16 cfm. Even if they mean average (15 sec) run cfm, it's not enough to grind.
 
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Old 09-16-08, 07:24 PM
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the difference is going to be in torque, i have two blue point die grinders and one uses a lot more air than the other both are rated for the same speed but the one that uses the most air has the most torque. by the way the high torque one is almost 2 times the diameter of the other one.

if we're not supposed to eat animals why are they made out of meat?
 
 

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