Airbrush Cleaner & Thinner Recycler
Being an avid user of an airbrush I was always hassled by the wife with smelling the fumes when I would clean my airbrush. I always needed a place to dump my old thinner as well. So it led me to make this cleaning/flushing system. As an added bonus, I now save and reuse more thinner than I had in the past, and it's kept fumes down, so that the wife no longer complains, and it reduced cleanup rags to almost nothing. I made my cleaner in less than one hour, from materials I had laying around, so no purchases were needed, but I would guess it could be made for less than 2 or 3 bucks if you had to buy the brass tubing and hose.
You will need the following:
Make sure can is clean and washed and free of any residual liquids. Wash with soap and water, and allow to dry. Then make a hole in the top of the can opposite the screw cap in the corner, to fit the 1/8" or 3/16" brass tubing. Make it snug so it holds the tube when it's inserted. The length of this tube needs to extend about 1" above the top of the can and go to within about 1" of reaching the can bottom. Next make a hole on the same side of the cans top near the screw cap to fit the 1/4" tube. Insert the piece of 1/4 x 1 1/2" brass tubing in this hole. Now solder both of these brass tubes in place. Your brass tube and hose sizes may vary as to your airbrush, and plastic bottle or funnels sizes. I found the dimensions given suitable for Paasche brushes, and the 4 oz. plastic epoxy bottles.
Next cut the bottom out of the squeeze bottle or use your funnel, and then slip a piece of flexible hose on the spout end, and then onto the 1/4" brass tube. The length of this hose is a matter of preference to the user. Now do the same on the other liquid supply tube, and connect it to the siphon tube on your airbrush. I usually use a color container, with the glass jar removed for this purpose. Other brushes may be different, but the intent is the same.
Then after your airbrush is connected to the cleaning reservoir, put in some filter media. This can be anything from cheesecloth, cotton waste to dacron 88 fiberfill. The purpose is to help trap and hold any solids from the paint flushed from the airbrush. It also helps to keep the thinner from getting stirred up, by the thinner getting returned to the can by the return line. Fill the can loosely to about 1/3 to 1/2 of the cans height with the media. Solids will accumulate in this media, and it can be removed when full by use of a wire coat hanger bent into a hook on the end, and just fished out of the can. Place some filter media in the plastic bottle as well. This will keep the thinner from splashing when you spray into it.
Put about 1 or 2 quarts of the appropriate thinner into the can, connect your airbrush to compressed air source, and direct the spray into the plastic bottle. While spraying, adjust the fluid and air valves, and continue flushing until its clear. I usually finish it off with a shot or two of unused thinner from a separate container, into the plastic bottle, after a thorough flushing. You may find you have to keep a shorter hose on the material siphon connection, but this depends on air pressure used, and the airbrush itself. It may be necessary to hold the air brush level with the top of the can until you get a flow of thinner through the airbrush. Since most airbrushes don't have the capacity to lift the thinner any great height, initially, but once it starts to flow, it can be raised to a more comfortable position.
That's really all there is to it. If the reservoir is mounted under the hobby bench etc, you will find that solids settle out to the bottom, and in most cases if it is not agitated, you will usually get clean or almost clean solvent for flushing your air brush. Some airbrush manufacturers make a device similar to this, but I usually like to make my own stuff if I can. Its cheap, easy to make, and does the job. Hope it serves its purpose for you to.