Airbrush Practice

Sometimes when I airbrush I end up with the lovely smooth finish and blends the equipment is known for. Sometimes I end up with a stippled surface, tide lines, spider legs, chipping and portals to hell on my miniatures.

I never write down or pay enough attention to what I'm doing differently. Now I want to paint a bit more seriously and sell things on a more regular basis to keep my afloat while I finish uni, I want to streamline and improve my use of the airbrush.

There's many ways to tailor the output of your airbrush which is why you can use it to achieve so many different effects and styles of painting. And screw it up in infinitely more ways. Well, really you can do anything with a brush that you can do with an airbrush. The difference is in speed and ability required. But, if you're making hundreds of mistakes and constantly trying to fix or cover things you cancel out any time gained. I know this well.

In true turbonerd fashion I sat down and wrote out what I wanted to achieve with my airbrush and what my current problems were and find solutions for both sets. Kinda looks like a pro and cons list to owning an airbrush.

Aims/Pros to airbrush use:

Paint quickly.
Easy blends.
Sweet blends.
Sweet blends on large surfaces.
Paint a go faster stripe on dog before anyone can stop me.
Good opacity with fewer coats.
More economical paint usage.
I like the smell of vallejo air colours.
I probably shouldnt be sniffing them.
But the smell does not dissaude me.
Smells good, trust me.

The main selling point of the airbrush to the new user is its speed - it lays down colour, and more opaque layers of colour. Faster than brushwork will with the same thickness of paint. Obviously if you load a brush with unthinned paint and slop it on it will cover faster than an airbrush with much more thinned paint. But consistency the same across both, the airbrush is much faster.

Airbrush also lays down a more even, opaque coat for the same amount of paint compared to with a brush. I have never bothered looking into why - something about how it lays down the paint compared to pulling a brush across the surface.

Highlighting with airbrushing is also much easier. With a brush you have to apply them individually and think carefully about where they'd hit. With an airbrush you can aim where your light is coming from, spray paint, and see where it hits and misses. With careful angling it's not going to hit the places that light would not hit if it was coming from the same location as your airbrush is placed.

Blending is easier because you can simply build up translucent coats of colour, with more layers going away from the point at which your colours join. It's how I paint my screamers. I put down a solid basecoat across the whole thing with one colours, then make up thinned and translucent mixes of the paints I want to go over it. Then I spray one or two coats over where I want the colours to join, then progressively more layers moving away from it and towards the area I want to be opaque in the colour I'm using. Sometimes I will instead lay down two opaque coats that meet together and then take a translucent mix of one of the colours and make a smooth join. Depends how big the area is, how lazy I'm feeling and what phase the moon is in.

Now, these only apply if you are airbrushing correctly. Which I frequently am not.

The model I am currently practicing on - a necron boomerang - now has a grainy surface from where I put down the basecoat colour like a chump.

Along with getting grainy surfaces I frequently end up with paint spidering out - where too much (often very thin) paint hits the same surface area and ends up being blown outwards in a bunch of different directions. Tide lines are common, something that happens with brush work as well.

The latter two - spidering and tide rings are my own laziness and incompetence. I have a habit of leaving my airbrush when it clogs or the paint flow changes due to drying inside the end piece. I just up my pressure or move the brush closer etc. Eventually the blocks clear and WHOOSH suddenly I have very high paint flow very close to my model. I struggle to mix and prepare paint that doesnt dry at all on the inside and cause problems.

For ages when I first started airbrushing I would spend so much time disassembling the brush, cleaning it, and wasting paint by havng to do so in the middle of painting that it became a very frustrating experience. It carried over - even now when I only have to clean out and clean up once in the middle of painting during a session over multiple hours I get really annoyed and either stop or try to blast through it.

That is simply fixed by relaxing when it happens, and sorting it out the moment it happens. I'm gonna read up some more on mixing paints and preventing drying.

The first problem is the most difficult one I have. Not achieving a smooth surface with an airbrush is down to the paint being to dry when it hits the surface, or layering too quickly or solvents evaporating weirdly. There's numerous reasons it can happen and multiple factors that can cause each to happen, or combine to cause it.

Air pressure, distance from surface, type of paint, type of thinner, thinner: paint ratio, drying time, humidity, temperature, and more things I probably haven't come across.

Its a butt.

I've done some reading around to see what seasoned airbrush users have to say about how they get smooth coats and thus far the common factors seem to be:

As low PSI as possible.
A proper airbrush thinner because the solvents evaporate at a different rate than water or water mixes.
Letting it dry properly in between layers.
Being around 8cm from the surface sprayed.
60-70% humidity.
Clean, smooth needle tip.

The basic goal is not letting any of the paint start drying before it hits the surface. You want it to hit the surface, level and then dry. This is still super fast when done properly. But if even some of your paint it drying on the way to the surface you have tiny, tiny spheres of dry material laying down and then being covered by water layers and sealed in place. Hence grainy surface.

I'm going to do a bunch of test spraying and write down how I actually do each run through and what it looks like. Sometimes I have to take long breaks between painting and when I come back I completely forgot what point I got to. Its very frustrating having to do trial and error testing with the same piece of equipment every time I start again.

I can't control temperature or humidity of my working area but I have enough other factors to fiddle with that it wont matter.

Time to go paint stuff badly, I guess.