In the grand scheme of airbrushes and sprayguns, choosing the right airbrush compressor is the least important step and, possibly, the most expensive step.
People who make the best choices answer these three questions first.
Here’s the basic formula to determine how much air flow capacity you need.
Look at your setup. How many airbrushes and sprayguns will you use at the same time? One after the other in succession doesn’t count. This gives you your Total Air Volume Needed.
Total Air Volume Needed is the bare minimum. No less. Don’t get anything that pumps out anything less than this number. Bad. Very Bad.
But there’s still something else to consider here.
Duty Cycle, normally given as a percentage, means the compressor engine should only run for that percentage of every hour the compressor is in use. It’s a good recommendation to follow as best you can to keep your compressor running for a long time to come.
50% Duty Cycle = 30 minutes running for an hour’s use.
25% Duty Cycle = 15 minutes running for an hour’s use.
Compressors, especially big ones, can be loud. Very,very loud. There are four ways to handle the noise.
In fairy tales everything always happens in a land far, far away–Snow White and the Seven Dwarfs, Cinderella, Sleeping Beauty, even modern fairy tales like Star Wars (I don’t know if I’d call Yoda a fairy god mother though…).
Lock your compressor away in the dungeon, or the tower, or banish it to New Jersey. The garage, shed, or even a closet work great if you don’t have you very own dungeon or convenient access to Trenton.
All of these methods work because noise gets softer with distance.
If you decide to get medieval on you compressor make sure your choice allows great ventilation, compressors use air after all.
Also, keep compressors out of the elements. Most compressors put up with the rain and snow.
Potential un-fairy-like problems.
Don’t offload your own noise problems onto your neighbors. Waking up the neighborhood in the dead of night because inspiration slammed you upside the head with a 2×4 is not nice.
Don’t forget to keep your compressor maintained. Out of sight, out of mind. Don’t fall into that trap. You’ll still need to drain the tank and moisture traps, check oil levels if applicable, blah blah blah.
If you’re the handyman, Do-It-Yourself, I-don’t-need-to-pay-someone-else-to-do-what-I-can-do-myself, person then you might build a noise box around the loud beastie.
I’ve seen untamed, very loud compressors become nothing more than the occasional dull rumble.
Just like the fairy tale treatment air flow is the problem.
Compressors use LOTS of air. Make sure they can breathe.
Quiet and even silent compressors exist out there [Click here for best silent airbrush compressors]. They range from low rumbles to a little louder than your refrigerator.
It’s story time!
Silent compressors can fool you about how loud they really are. Many times the fan that cools them is louder than the engine pumping the air. How do I know?
When you start work on a compressor you depressurize the air tank first.
I opened the air tank drain valve. The air rushed out (incidentally the compressor was shipped full of compressed air). Air tanks don’t take long to depressurize, a few seconds, maybe ten. The air kept hissing out. I stared, puzzled, at this compressor after a full minute of flowing air. How can an air tank have that much air in it? What’s going on? I’d turned it off!
My instructor looked at me. Rolled his eyes and flipped the power strip off. The tank stopped spewing out air. Heh heh…umm….whoops.
Yes, the compressor was running while I was working on it. Talk about embarrassment…
These compressors do tend to be small. They can range from a few pounds on up to 50 or 60 pounds.
Smaller sizes make them far more portable than bigger, louder compressors. The smaller the compressor the less capacity that compressor has, but depending on your application that could be a very acceptable trade off.
There is one major down side to quiet and silent compressors.
Airbrush compressors are expensive because making noise is easy and making a mechanical device that doesn’t make a lot of noise, isn’t.
You can do the comparison and see for yourself.
Walk through the aisle of your local hardware store. The compressors there aren’t that expensive. Not only that, but they have a lot of power. They can move a lot of air and pump it up to high pressures quickly. Sounds great doesn’t it?
Ahh, but sound is the catch.
Turn on one of these inexpensive beauties and you’ll understand immediately what it means to be unable to hear yourself think. In fact, most compressor manufacturers don’t attach decibel ratings to their products.
Decibels are a method of measuring noise intensity. These compressors are intense when it comes to noise.
On the other side of things is the quiet and silent compressors
Quiet compressors generally top out around 55-60 db (decibels). But what does that compare to exactly?
The decibel scale is logarithmic. That simply means that for every 10 points higher on the scale the sound is 10 times louder. The reverse is also true. For every 10 points you drop on the scale the sound is 10 times softer.
So the difference between 60 db is 100 times louder than 40 db.
Silent compressors top out between 50 and 55 db. The price also goes up by roughly 4 times for the quieter compressor.
This is an elegant solution. Why?
If compressed gas is so great why doesn’t everyone use it?
Technically, everyone uses compressed gas. Compressors pressurize whatever gas they’re pressurizing and pressure cylinders (tanks) store the compressed gas for use later. But that’s getting technical.
There’s no engine. The engine is what makes the noise, uses electricity, and compresses the air. It’s just a tank of high pressure air.
Experienced users horde an extra tank or two for the inevitable ‘I just ran out of gas in the middle of what I’m doing!’ moment. Local welding supply, and beverage supply companies are your friend.
The risk is really, really small. This risk so small that it’s a non-issue. I mention it because if you do suffocate yourself, it’s completely your fault, because it’s easy to avoid.
Here’s how to avoid suffocation. Ventilation. You shouldn’t spray in an enclosed space anyway, so you shouldn’t be able to drown yourself by displacing all the breathable oxygen.
This is another very small risk that’s completely avoidable.
Rough handling that knocks or shears off the head allows all the pent up gas to escape turning the docile air tank into a torpedo.
Avoid this problem by not handling the air tank roughly. If you can strap the tank against something else upright to avoid the tank falling over.
For whatever reason, if you discover problems finding or running power to your compressor do one of these two things.
Make sure the generator will put out enough power for your compressor. You might want to talk to the compressor’s manufacturer and ask them about the start up power surge. Your generator will need to put out enough power to cover that initial surge.
Finding good steady power at the fair grounds or for a mobile service is murder. A #20 CO2 or N2 tank frees you from the power grid nightmare.
An air tank on a compressor is a good thing. Your compressor with a tank will run longer than a compressor without an air tank. It might cost more, but it’s a good thing.
Compressed gas users don’t need this advice. Welding supply or beverage supply stores sell dry gas.
Air compressors must have a moisture filter and an air filter, but they might not come with the compressor you purchase.
Moisture filters remove the compressed air’s water vapor before the aerosol spray mixes with it. The paint type you use determines what kind of bad results you’ll get. But no one wants bad results. Unless you live in New Mexico, deep in the Sahara, or in Antarctica, get a moisture trap.
If you live in extremely humid places like Hawaii, on or near any body of water’s coastline, or in the tropics, you might need to do more than purchase a moisture trap.
Dry air beats humid air every time. Don’t forget it.
Both control the amount of air delivered to your tools. But they control airflow very differently.
Bleed valves adjust the pressure by removing air from the pressurized air system before you have a chance to spray it. They bleed air like medieval doctors bleeding their patients.
Air regulators adjust the pressure by allowing controlled amounts of air from one part of the pressurized air system into another. It’s like the on-ramp traffic lights on many freeways. The lights regulate traffic onto the freeway. Regulators regulate pressure into the air line.
You need enough air to run your equipment. Choosing the right air source will keep you on the right track to starting airbrushing right.