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I have a question about air compressors. I got my hands on a air impact driver and ratchet and I work on cars around here for extra money while I’m going to school and I keep forgetting to ask my teachers this but my question is what is the lowest gallon of air compressor you can use to get the job done ie. Remove lug nuts, head bolts etc. I heard 30 gallon is the minimum but I was wondering is there any less of a gallon the reason being is air tools would save me a lot of headaches but I don’t have a lot of money. Thanks again
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All depends, your house electricity delivers about 15 amp and your air compressor takes 15 amp. So if you have dedicated power, with 30gal compressor you should be able to run (kick in the motor of the compressor) every 5 minutes without triggering the circuit breaker – that is if you are using electric compressor. So big question is how much air can you use in given time? If you use air grinder or drill you can use 20 – 30 PSI in a minute. if you use impact wrench, it will use less air but it all depends on the impact wrench – if you use cheap impact wrench it would take more air to operate compare to more expensive models (Air consumption is measured in CFM – Cubic Feed in Minute) Not only you have to look at total size of the compressor, you have to look at how fast your compressor can charge the air. If you are running 4CFM tool, and if compressor delivers 2 SCFM(Standard CFM)@90 PSI, you are going to run that compressor all the time or burn it out.
So with 30 gal tank, the only thing you are using is the single impact wrench that is rated 4 CFM – it should be enough as long as your compressor can deliver least 4 SCFM@90PSI. But if you are operating Air grinder, it will give you about 30 seconds of service and the compressor will kick in (and if you keep this up, the breaker will drop). So buy the biggest tank you can afford with the highest SCFM at 90 PSI. The most of the air tools I have requires about 3 – 4 CFM.
There is already a thread in the tool section regarding compressor with a lot of great information in C8-)
Some air tools use a lot of air, others use a real lot of air. Like Skim said, stuff that is run continuously like grinders will consume air very fast and no homeowner type compressor (or even a small pro unit) will keep up if you run the grinder constantly. Stuff like air impact wrenches or ratchets aren
The single most annoying problem is when that air compress runs and takes down your breaker. You only have 15 amp service for standard electric line. You can actually work around by running a electric sub panel with 20 amp fuse. This will require you to replace all electric lines in the room and installing a sub panel. After this change, your compressor can run as more frequently without dropping the breaker. (but compressor can actually burn itself out due to heat build up) If tank space is a problem, you can also add a extra tank inline.
The second most annoying problem is noise. Man, that thing is loud!!!
Especially the ‘oil free’ kind which many of the homeowner models are. When I switched to the oil lubricated type the difference in how much less noise it made was amazing.
A 25 gallon tank should be fine for a impact and air ratchet ( my campbell hausfeld has a twenty gallon tank and runs the impact and ratchet just fine , although it is not sufficent for my air powered drill , grinder , sanders – it will run them but cycles on / off rather often ) mine has a 3.5 horse motor. I would not go any lower then a 3 horse motor.
I’m not sure how a 25 gal tank is supposed to be comparable to a 60 gal tank – that’s like saying 3 cans of beer is comparable to a six pack. A 60 gal unit will give you quite a bit of reserve (probably overkill for home use), the 25 won’t and as DioFan said, will cycle more often. Where it may be similar to the 60 gal unit is in the scfm rating. It sounds like a reasonable unit. Just remember, if it’s the oil free type it will be loud.
House is wired for 15 amps. If cycled on/off too often, it will cause the breaker to drop. I have 30 gal and is barely enough to keep up with my IR 3/8 impact wrench. 4.7 scfm @ 90 psi and tool normally uses 4 CFM so it should be (barely) enough. I get by replacing all garage lights with energy efficient bulbs and disconnecting everything from garage.
There is already a thread for air compressors in the Tool section. There is a lot of good information there.
This is for service and repair C8-)
I agree johnzcarz I don’t know how a 25 gallon can be compared to a 60 gallon. I decided not to get it I trust you guys way more than someone telling me that stuff. I’m very desperate for an air compressor and don’t have much cash and I believe the right one will come to me when It’s meant to. Thanks so much everyone you guys have helped me so much.
I am looking at an air compressor and I was looking at the specs you guys said before and I was wondering if these specs would work on what I would use it for. I need it for air tools mainly impact drivers and ratchets. Here’s the specs: It’s a porter 25 gallon and they said It’s suppose to be comparable to a 60 gallon. Air delivery 4.9 scfm @ 40 psi and 4.7 scfm @ 90 psi. Running hp is 1.6 and It’s a 15 amp if that matters. Thanks a lot
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