To understand the properties of paint is imperative for airbrush artists. The best equipment will not make bad paint spray well, especially when attempting to spray fine detail.
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| Media spray cone of an airbrush |
Before going into the hazy realm of mixing the right additives to paint, it is probably helpful if there is some level of understanding of what additives actually do in cooperation (or conflict) with pigment particles inside the brew known as paint. The article that is placed here may be helpful in reaching a higher level of awareness concerning this matter. This example is done with a hairy brush, but it works the same for airbrush.
As is the case with everything else in life, understanding the complexity of the properties of substances and liquids that are mixed to make a paint, requires some effort. But it may assist artists in choosing the right additives, on which I may elaborate in a future blog entry. The problem that most artist have in this respect, is that few of them own a laboratory where they can test how well or bad the theories that they or someone else has conjured up work in real life.
I once was in the process of creating a new paint once and I had some brands of the competition examined by the university of Groningen in The Netherlands. They told and showed me that all paints contain a lot of masking liquids which purpose is to throw off enemy researchers so that they could not figure out which substances actually do something useful (or not) in the paint. But however little of such liquids is present in a paint, they do something to a varying extent. Which makes searching for the proper additive difficult, because it may react slightly different to the paint than mixing the same retarder with a different paint. This makes paint manufacturers, practitioners of what looks to be some sort of a dark art.....
I once was in the process of creating a new paint once and I had some brands of the competition examined by the university of Groningen in The Netherlands. They told and showed me that all paints contain a lot of masking liquids which purpose is to throw off enemy researchers so that they could not figure out which substances actually do something useful (or not) in the paint. But however little of such liquids is present in a paint, they do something to a varying extent. Which makes searching for the proper additive difficult, because it may react slightly different to the paint than mixing the same retarder with a different paint. This makes paint manufacturers, practitioners of what looks to be some sort of a dark art.....
The rule of thumb in general is to mix the paint with flow improver, a.k.a. isopropyl, which does what its name suggests and keeps the internal of the airbrush cleaner and therefore easier to clean when an airbrush session is done. Also surfactants do a good job, because they break down the bond between the solvent (water in acrylic paints) and the structure that contains the pigment. These additives do not reduce the amount of pigment in the paint, but lower the surface tension between the pigment and acrylic binder, which makes the paint easier to spray and keeps the airbrush cleaner for a longer period of time, while not reducing the colour intensity of the paint. Thinner and retarder I rarely use, because their improvement of handeling the paint is not quite as noticeable when using the prescribed measure of them or mess up the paint behaviour when adding too much of them. For reference I use Holbein Aeroflash acrylic paint and I am considering using Holbein's new Acrylic Inks in the future. An other paint I have good experience with Vallejo, that also sells its own flow improver. This additive also works well with Tamiya alcohol based paint.
In general, assumption is the mother of all evil, but to assume less by knowing more, is the best option most artists have, to avoid becoming involved in the evil practice of stirring substances and liquids that allow to do magical things. To reduce the effort, time and frustration that the trial and error method may inflict, getting a grip on what is explained in the article mentioned above, may make an airbrush artist's life somewhat better. Since all brands of paints and additives have their own particular mix of chemicals, it pays to experiment to find the proper mix ratio to work with.
Meanwhile, practitioners of the airbrush trade may want to take a peek at this guy's efforts to figure out what additives work and which ones don't. Flow improver also extends the drying time a little, which allows the pigment to disperse better in the airbrushed surface after t has been sprayed on to it, resulting in a more even and smoother and more even cover of paint.
Meanwhile, practitioners of the airbrush trade may want to take a peek at this guy's efforts to figure out what additives work and which ones don't. Flow improver also extends the drying time a little, which allows the pigment to disperse better in the airbrushed surface after t has been sprayed on to it, resulting in a more even and smoother and more even cover of paint.
Testing of flow improver
Some additional information on how to use additives is provided in the video below. Besides mixing additives to the paint, this airbrush artist recommends using demineralized water as opposed to untreated tap water, because it contains less calcium (which is the component that makes the airbrush clog faster), to which I agree wholeheartedly.
More info on how to prepare airbrush paint
A comprehensive comparison of additives that airbrushers use - flow improver and thinner - in a clear visual way in the video below.
Comparison between flow improver and thinner
