I had an interesting chat with a customer today regarding airbrushes, their cost and quality.
He had bought one the cheaper models, under £50 from that online store that has the same name as a river.
He was having problems with it, spitting and continually clogging.
I explained to him that all airbrushes will clog, the spitting is a different matter.
Cloggin is caused by the paint drying on the needleresuklting a in build up of paint completely blocking the nozzle in his case. It can be down to a poorly finished needle, too low air, or too thick a paint, it can happenf if the room you are spraying in is too warm.
Ideally with pre-mixed paints like Vallejo Air, and Game air you should be spraying at about 15 -18psi, this should be enough to atomise the paint as it leaves the nozzle and give you a fine even coat with decent size cone.
If the air brush clogs, try adding one or two drops of flow improver (retarder) to each cupful of paint, this slows down the paints drying time.
If the paint still clogs with paint pre-thinned you may need to look at the state of the needle.
Generally needles in cheaper brushes are not that well finished, they are not that smooth, paint collects in the tiny scratches in the metal, especially if the needle is a softer metal, you may even have a slight hook on the very tip of the needle, test for this by rolling and dragging the needle on some fine cloth, if it catches you have a hook in the needle.
You can polish the tip of a cheap needle with some 2500 grade aluminium ooxide paper.
Gently wrap a piece of the paper around the tip of needle and rotate it in one direction, for a finer polishing you can also use Jewellers rouge, (very expensive stuff) or a polishing compound.
Next you need to find a model shop like Test Valley Models that clean and service airbrushes.
We use isopropaqnyl and 40mins in an ultrasonice cleaner to give your brush a really deep clean, we only use interdental brushes for cleaning the nozzle and jets in the brush.
Finally we oil the trigger valve, and needle with Iwata airbrush oil.