Any well-stocked garage should probably have an air compressor. Surprised? You’ve gotten by for how long without one? Well think again because an air compress is a great pickup.
An Air Compressor’s Many Uses
An air compress is a tool that creates a high pressure storage zone for compressed air and then releases it on your command. Why is that useful? It’s like a reverse vacuum or a leaf blower, except with many tool attachments.
Here are some common uses of an air compressor in a home setting:
- Cleaning dirt out of your garage
- Blowing away wood after sanding (and before painting) furniture
- Filling bike, car, and wheel barrow tires
- Filling balloons
Here are the parts of typical air compressor:
The main user interaction points are the on/off switch, the output pressure adjustment (this can be closed entirely), and the output port(s). The output port will connect to a hose that connects to your attachments. Most of these will be obvious, but it’s worth noting the output pressure adjustment — it’s regulator between the stored air and the hose that controls the pressure of the air being released from the tank.
Not shown on the image but it’ll be obvious on most models is a safety valve that can be pulled for quickly draining air from the tank without using the attached tool. You’ll want to pull this each time you are done using the tank because you’ll never want to store it at pressure. Pressurized air can create condensation which, over time, can rust out your compressor tank, hence the drain valve at the bottom.
Some popular attachments are:
- Blow gun (how you blow high force air out of the compressor)
- Blow gun with extension
- Dual-head air chuck inflator for Schrader valves (used to fill a bike or car tire)
The blow gun can also have its own attachments, like a rubber tip for getting under surfaces or a valve for filling a basketball. Attachments are normally sold in kits, that go for about $25-$50. Such kits are included in some air compressors but won’t be found with base-level models or in professional-grade ones.
Air compressors can also drive power tools, like an air hammer, impact driver, brad nailer, or reversible drill. Tools like impact drivers and grinders are typically restricted to larger, more powerful air compressors and you can’t efficiently drive them with a typical 6-gallon home compressor. Look at the CFM and PSI demands on the tools you want to use and you’ll know what compressor to get!
The easy thing to do when shopping for an air compressor is to look for the capacity (in gallons or liters) and the PSI, and then buy the compressor if those look good. But don’t miss out on checking the Standard CFM (SCFM), which is a measure of airflow from the compressor. After all, high pressure (measured in psi) in the tank is only useful if the air can be put to use. This is exactly what the CFM measures.
Think about it like this: a home compressor like the Porter-Cable below has enough pressure to operation a nailer — because it has a high psi — but moving a nail takes a lot of pressure, not a high volume of air. Operating an air hammer or grind wheel requires minutes of usage at high pressure, which means high sustained CFM output, not just high psi. Typically a home user will need 2-5 SCFM, but this can vary greatly depending on the work you plan to do.
At the very bottom of the article you can find some minimum air tool requirements for SCFM and pressure. These will be home garage level tools, not pro-grade ones you’d find in a shop. Keep in mind you’ll need very little SCFM for a brad nailer (around 0.2) but a lot for persistent tool, like a die grinder (7 SCFM). In the middle range you’ll have your nibblers, impact drivers, and drill tools.
Air Compressor Parts
If you are new to air compressors you might need some explanation on what you are looking at. A typical setup, like on my Porter-Cable above, will have just a few parts you need to know about.
- Tank Pressure Gauge – Indicates the air pressure on the inside of the tank
- Regulated Pressure Gauge – The pressure sent out to the hose. Always less than the air tank pressure
- Regulator – A knob that lowers the pressure from the tank to the outgoing hose
- On/Off Switch – Turns the air compressor on and off
- Safety Valve – This will open if the internal pressure is too high. It can also be pulled so that you can remove the air pressure from your tank. A tank should not be left under pressure when not in use.
- Air Hose Exit – A quick connector where the hose can connected
One important item not pictured is the drain valve on the bottom of the air compressor. This is used to drain the bottom of the tank when you are not using it. The tank hold air at high pressure, which causes water to condense on the inside. You don’t want this water sitting at the bottom of your tank, so you need to drain it occasionally.
What To Look For In A Compressor
Home buyers who are new to air compressors usually buy them because they have a specific purpose in mind, like needing a nail gun for an upcoming project or because they want to outfit a garage workshop.
The typical purchase that makes sense will be:
- Pancake-style air compressor
- Oil-free design
- At least 5-gallon capacity
- Over 120 psi maximum air pressure
Secondary considerations should be the SCFM, size, noise level, warranty, accessories, and of course the price. Keep in mind that the price will vary greatly based on the included accessories — a well-kitted compressor might cost twice as much as a barebones one. You might also want to consider the weight and amount of horsepower. More weight and more horsepower aren’t sure-fire signs of quality, but they are indicative of a better compressor.
Many people prefer an oil-free design because it produces cleaner air and less emissions when operating. Oil-free designs are also mandatory for operations in some professional settings, particularly those indoors. Generally speaking, oil-free will be the way to go for the home or light-duty user.
Best Air Compressors
I personally use a Porter-Cable pancake model that is no longer in production (shown above). It’s a 120 psi, 6-gallon unit that has been problem-free for years. I’d recommend it, but it’s no longer for sale. As such, the nearest equivalent is my top pick.
Note: Most base models don’t include a hose or attachments, so they aren’t usable on their own.
Porter-Cable Model C2002
The Porter-Cable C2002 is a top-selling compressor with great reviews, and it looks great on paper. The top-line specs are…
- 150 psi max pressure
- 6-gallon capacity
- 2.6 SCFM at 90 psi
- Low-volt motor for easy cold weather starts
- Oil-free design
Normally we’d recommend a bigger name, a Dewalt say, but having had my Porter-Cable for so long, the C2002 seems like a downright reasonable choice. It sells for under $100 for just the air compressor or $170 for the all parts you need to get started. Most home buyers will want to go for the full kit, but if you have some parts from an old compressor then you can get away with just the compressor itself.
Bostitch Pancake Air Compressor Model BTFP02012
Bostitch’s entry-level BTFP02012 (the yellow model pictured above) is quite similar to the Porter-Cable. It’s a 6-gallon, pancake air compressor with a 150 psi maximum pressure. In fact almost all the specs are the same as found on the C2002.
One difference between this and some other models is the quieter operation, 78.5 dBA in fact. Now that’s not exactly quiet, but it won’t deafen you if the garage doors are shut. At 17 x 17 x 19 inches the size is about average for a pancake compressor.
The Bostitch and Porter-Cable models look to be almost exactly the same, but from our research the Bostitch has a longer hose (about 2 feet longer) and there is a 3-year warranty from Bostitch as opposed to 1-year with Porter-Cable.
One downside is that the motor is just 0.8 horsepower so refill times aren’t as short as they could be.
Makita MAC2400 Air Compressor
Another top pick in the home garage air compressor world is the Makita MAC2400. This compressor has some clear changes from the previous two models. First of all, it’s a dual-tank design (called a “twin stack”), not a pancake, and it’s also oil-lubricated.
This model has more power and higher specs than the other two. What that means on paper is you get 4.2 free air CFM @ 90 psi, up from 2.6. You also get about three times the horsepower of the previous models — 2.5 horsepower vs. 0.8 from the others.
There are some downsides with this model as well though. First of all, it costs a good deal more than the others. It also weighs a hefty 77 pounds, so you aren’t moving this one around too often, even if it is a little bit smaller than the pancake models (18 inches high and 19 inches wide). It’s also a little bit louder than the Bostitch, at 79.0 db.
Long story short: the MAC2400 air compressor can power two nail guns at once and the previous two can’t. There is a good chance that doesn’t matter for you, but it can make a huge difference if you are working with a team.
If this sounds like more than you need, you can look into the Makita MAC100Q or the very popular MAC700. The MAC700 looks smaller, lighter, and easier to move around, but it’s still 60 pounds, so don’t be deceived into thinking it’s light duty. It’s best to see one in the store before ordering online if at all possible.
- What is an oil-free air compressor?
Some air compressors are oil-lubricated while other are oil-free. Oil-free air compressors do not use oil to lubricated movings parts, but rather have replaceable parts and special low-friction surfaces them. Oil-lubricated air compressors used to be quieter and longer-lasting than oil-free models, but that's no longer the case as oil-free designs have improved greatly over the years.
- What is a pancake air compressor?
A pancake air compressor is a model with a single tank that is a flat, elliptical (or saucer) shape. Pancake compressors are typically used for home usage with tanks that are under 7 gallons in volume. The design is lightweight but awkward to carry because the width of the tank.
- What is a hot dog air compressor?
A hot dog air compressor is a model with a single tank that is long and shaped like a pill or like a short hot dog. The shape is typically easier to carry than a pancake compressor, but is heavier for a given air volume. A typical hot dog compressor for home use is the Makita MAC700.
Air Tool PSI and SCFM Requirements
|Tool||Pressure Needed (psi)||SCFM Needed (@90 psi)|
|Brad Nailer (18 gauge)||70||1.2|
|Impact Wrench (1/2″)||90||4|
|Impact Driver (1/2″)||90||4|