Editor's Note: While foraging around the web one day looking for parts for my Iwata, I stumbled across Jay's website. Since I have a profound respect for anyone who can draw and airbrush, I spent some time on his site...and his work is incredible, even if it's not ships :-) Although these articles are written for aspiring airbrush artists, modelers can learn alot from folks like Jay. I'd like to thank Jay for allowing us to use his articles to help out modelers who are intimidated by airbrushes, and to those who are just getting started. Thanks Jay!
A well maintained airbrush is a pleasure to work with, and will last a lifetime. A poorly maintained airbrush is a fifty dollar paperweight. I can't emphasize enough how important it is to clean your airbrush thoroughly every time you use it. There are three types of cleaning. The during use cleaning, the end of session cleaning, and the tune up. For the following instructions, I'm going to assume that you are using a double action airbrush with water based paints. If you are using a single action gun, it should be easy to modify the instructions to your needs. If you are a beginning airbrusher, you really shouldn't be spraying anything but water based paints. Leave the urethanes and the enamels to the pros.
DURING USE CLEANING
When spraying, you will need to clean your airbrush out thoroughly when you change from one color to another. This is especially true if you are changing colors that are very different, like changing from purple to yellow. If there is any purple still inside your airbrush, it will ruin the yellow you will spray. Also, paint tends to build up inside the airbrush, especially on the needle, and you will need to rinse out this paint in order to get fine lines, and smooth, not sputtering spray.
If you are using a siphon feed or side feed airbrush, fill up a siphon jar or cup with water, and keep it handy when painting. If you are using a gravity feed airbrush, fill a small jar with water, and keep a eye dropper and a cheap round paint brush handy.
You may add a few drops of airbrush cleaner to the water if you are using acrylic paints. Don't overdo it though; airbrush cleaners are somewhat toxic. If you are using a water soluble paint, like watercolor or gouache, plain water will be fine. If you are using an airbrush with an unusually fine tip, distilled water may be worth buying. Minerals in tap water can build up in fine airbrushes and clog a fine tip up.
When it comes time to change colors, start by using your water to spray water through your airbrush. It is a good idea to have a container to spray into, to minimize paint mist. You can make a fine 'cleaning chamber' from any container with a plastic lid. Coffee cans and Cool Whip tubs work fine. Cut a hole in the lid near the rim, just large enough for the air cap of your airbrush to fit in. then cut a few smaller holes on the other side of the rim for venting the air, to prevent blow back. Finally, put a damp sponge inside the container to trap paint. Loofa sponges work really well for this, but a plain dish sponge will work in a pinch. Of course, you could go out and buy a cleaning chamber from the art store, but they are very expensive and don't work any better than homemade models.
After you have sprayed some water through the airbrush, the next step is to back flush. I should warn you that some models of airbrushes are much easier to back flush than others. The important element is the aircap. You want a simple conical aircap. Crown Caps and 'paint picker' caps are difficult to back flush.
To back flush, first pull back on the needle, without pressing down on it, and with your water jar still attached. Put your finger over the aircap, to block the airflow. Press down on the trigger just a little bit. Not more than a quarter of the normal travel length. You should see bubbles in your water jar. If you press down too hard, you will get a giser coming out of your water jar's air hole. If you are using a cup instead of a jar, or are using a gravity feed airbrush, only fill the cup half way up, to prevent spilling. If you are using gravity feed, use your brush to wipe the inside of the well, to make sure there is no more paint sticking to the side, then back flush a second time.
If you have an airbrush that is difficult to back flush, do not despair. You will just have to spray through clean a bit longer, that is all.
If during your spraying, you find that your airbrush is clogged up, first try to blow out the clog by spraying into your cleaning chamber, and pull all the way back on the trigger. Some models of airbrushes have holes cut in the handle so that you can pull the needle back even farther. This really helps blow out clogs.
If your airbrush doesn't have this hole, you may want to consider removing the handle while spraying. Many airbrush artists prefer to spray withough the handle. But don't through it out, its good for keeping dust out of the internal parts while the airbrush isn't being used.
If you can't blow out the clog, then do a spray through cleaning, and a back flush cleaning. Also, once in a while, when spraying for long sessions, pull the needle out and wipe it off on a paper towel. That will help prevent clogs before they happen.
After you are all done for the day, fill a bucket half way up with warm water. Place the front end of your airbrush into the water, just far enough so the siphon hole or gravity feed well is underwater. Then press down and pull back on the trigger, just as if you were spraying a lot of paint. The warm water will cycle through the airbrush and flush out any paint inside. You can also clean out siphon cups and siphon caps by attaching them to the airbrush, and flushing them out in the same way.
Be careful to keep the air valve above water. Air valves have a little washer inside them that does not like to get wet. If it gets too wet, it will swell up and jam up the air valve. You would then have to disassemble the valve to free up the washer.
After you have flushed out the airbrush, pull out the needle and inspect it for paint. It should be clean if you have flushed the airbrush out enough. Also check the aircap and siphon tube hole for paint. A toothpick is useful to scrape off really stubborn paint. Metal Polish is also good at removing paint. You can polish hard to reach spots by taking the corner of a paper towel and twirling it into a point. Metal Polish and a twirled paper towel is a great way to clean dried paint out of tips.
A variation of the bucket flush cleaning that I've just described is to use a water pick. Water picks are sold at drug stores and department stores for cleaning your teeth. Many airbrushers use these things to clean their airbrush. They are a bit expensive though, and I've never had a problem with the bucket method, so I recommend that you try my method first.
Before putting the airbrush away, check the needle and tip for wear. Run your finger over the tip of the needle; it should feel smooth, with no burrs. Make sure the needle is straight and not bent by placing it on a hard table top. It should rest flat. Check the tip for a blown out opening. The shape should be perfectly conical, no flair at the end. If the flair is bad enough, there will probably be a hairline crack too. Use a magnifying glass to check.
A needle with a burr on the end can be reshaped with a fine sharpening stone, the kind used for sharpening pocket knifes. You will only be able to get away with this once or twice before the needle will have to be replaced though.
If the needle is bent along its length, you may be able to straighten it out a bit by rolling it along the table and pressing down hard on it. If that doesn't straighten it out, the needle should be replaced.
A blown out tip can still be used if the blow out isn't too severe. You will not be able to get as fine a line as you could with a new tip though. If the blow out is very bad, or if there is a crack in the tip, replace the tip ASAP.
Every once in a blue moon, you should strip your airbrush down as much as you dare, and soak everything in mineral spirits. Everything except that little washer in the air valve, that is. If you don't want to take the air valve apart, then just soak the front end of the body shell. Badger's 2 oz. siphon jars are just the right size for soaking just the front end of the airbrush.
Let it soak for a few hours, then wipe it all off with paper towel, inspecting for dried paint as you go. Take the metal polish to any paint you find. Let the airbrush dry for a while before putting it back together.
When you do put it all back together, generously lubricate all the moving parts with Vaseline. Especially the trigger's stem, the rocker arm and the inside of the needle valve assembly.
Keep your owner's manual handy, as this will have a diagram showing how all the parts fit together.
When you are done with the mineral spirits, do not dump it out. Strain out all the paint and gunk with coffee filter, and store the spirits in an airtight container for next time. This way, one quart of mineral spirits will last you a lifetime.
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