I do this:
- take it out of its box
- unlock the needle, push it forward lightly until I feel resistance, lock it.
- attach it to the compressor, turn the compressor on
- adjust pressure to something between 20 and 60 PSI. Most of the time low, around 25
- check nozzle free, mechanics all moving
- put some water into it and see if it comes out nicely, onto a piece of paper towel.
For the paint I tried putting it into the airbrush undiluted (some of my Army Painter paints are quite thin), diluted with a drop of water, or with Vallejo airbrush thinner. I tried everything between
- so thin it looks like a wash on the model, runs away and doesn't cover at all
- so thick it only takes 3-5 seconds to completely clog up the nozzle
I tried mixing the paint in the airbrush's cup (not good) and mixing in an external container (better, although wasting lots of paint because I have to use a pipette to put the paint into the airbrush and I can never get all the paint from there. It triggers my OCD immensely).
Anyway, after that I start painting.
I usually do a quick spray on a piece of paper to make sure there's no funky $*** going on, then I spray on the model.
I am not very good with coordinating the two functions, so I usually pull back the trigger to get the air fully (that's why I set it low on the compressor), and then slowly depress the trigger to get some paint in.
While spraying I keep the airbrush mostly level or facing a bit downwards.
Problems I encounter:
- the nozzle clogs. Then it starts splattering around.
- even while the spray picture looks pretty decent there are tiny drops around the area I spray, similar to when you use the toothbrush technique to paint stars. I tried to prevent that by moving the airbrush closer to the target, but then it starts blowing the paint around on the model, even with fairly low pressure. It also takes ages to spray the model then because I paint only very small areas.
When priming I take off the nozzle cap, otherwise the primer clogs it because it is pretty thick.
Priming works decently then. Nice thin primer coats, although far less quickly than I had hoped.
Both when priking and when basecoating I keep a paper towel and some isopropyl alcohol near, to clean the nozzle.
After use I clean it of course.