Have a look at this one for thinning your paints. This bloke uses windex. I use Rubbing Alcohol. Exactly the same principle works on all paints. If you don't thin your paint properly you will have a nightmare of an airbrushing experience. Another tip, keep your airbrush clean. Cheers Paul
Only one or two things I've found that really help.
-Test on card or styrene first before defacing a new model! The first few lines can be a bit uneven as you get your eye in. -Keep your paint to the consistency of milk - thick paint=blockage! -Don't be too ambitious the first few times. -Give paint time to dry properly before removing masks (and don't let paint build up too much against a mask or you will get a step). -Keep you cleaning stuff close to hand! Somehow I manage to cover myself in paint every time ... not to mention eveywhere around me. -Clean stuff vigorously after use. Nothing worse than nothing working properly because you were in a hurry last time (I'm too guilty of this).
Definitely get a compressor. Using the cans will drive you nuts.
If you are using acrylic paints, buy a can of airbrush cleaner. It's the only thing that will get the stuff off the innards short of taking the brush to pieces every time.
Experiment on scrap to find the amount of thinner you need to add. This varies from one paint manufacturer to another so it's hard to advise. I find Tamiya paints are good to spray, they have to be thinned with isopropyl alcohol (rubbing alcohol). Thanks to Parus Ater for the advice on that one.
If you are using GW or ordinary Vallejo paints then thin with distilled water with a little windex added.
Contrary to instinct, if you are trying to spray fine lines or details, you need to turn down the pressure of the air flow.
Get one of those sealed jar things for cleaning the airbrush (you stick the brush in a hole in the top and blow cleaner/thinner through it).
It's probably a good idea to buy a supply of disposable gloves to wear while airbrushing. The blue nitrile ones are the best. I should note that I don't personally heed this piece of advice. But I'm a messy ******.
Make sure you have lots of pots, tissues and cotton buds to hand. Airbrushing seems to consume vast amounts of such things. Also LOTS of thinner.
If you don't have a spray booth you can approximate one by cutting the top and one side out of a big cardboard box. I use one a printer came in. It at least stops most of the overspray.
Have some strategy in mind for moving/rotating the model while you spray it. A temporary handle or a little turntable maybe. Fiddling around trying to move something without touching it is not conducive to good airbrushing. On which subject, does anyone know of a supplier of little turntables? Like the ones cake decorators use but smaller would be ideal.
Things I've found useful - get your hands on a 5ml syringe or two, handy things for brush painting as well. I used a diaphragm compressor and if it's been on for too long it gets hot and moisture condenses and it spits so make sure you turn it off when you're changing paint and in the winter if you have a 5m hose you can stick it outside and it never gets hot at all if you keep turning it off when you're not using it.
I also use cans if I get the need to paint at night but you need two and a hot water bottle since using them reduces the internal pressure and the cool down, again, reducing pressure so you switch and put a hot water bottle on the cold one.
A lot of the online tutorials for airbrushing models tend to be quite involved but there's a Polish chappy who sounds like he's threatening you I follow on youtube. Here's one he did for the GW Valkyrie kit that shows you the basics of airbrushing like preshading and highlighting. http://www.youtube.com/watch?v=je9rKSOtYAc
You should be able to follow that with any tank, really.
Compressor is a must, and not an "airbrush compressor"; you want one with a tank or it will "spit". Mine was officially purchased to blow out my sprinkler lines in the fall
I use blue windshield washer fluid, for the car, and it's great. Just a hint of soap, some alcohol, and I hope non-toxic. Cough. Cough. Vallejo Airbrush thinner works well too, but doesn't dry as fast. Skim milk is the consistency I use, about 1:5 paint:thinner.
Oh! I use a 3M mask so I don't breathe the atomized paint and thinner! No cough.
I use an Iwata HP-B and a pair of Badger 150s. The Badgers are nearly as old as I am, one is fitted with a broad tip, the other thin. My Iwata is the gem - gravity fed and insanely precise. I love it.
I used an old 1:35 M113 as a "spray hulk" to learn on. It was very handy.