There's been quite a few threads lately asking questions about customizing. I encourage new customizers to please check the Custom Tips and tutorials thread before you post a thread asking questions. A great deal of work has gone into compliling all the tips available in that thread (and as always we're open to PMs with suggestions for the thread )

However, the question that seems to get asked the most is about paint grades and what paint to use. Because of this I've decided to address this common question in a seperate thread that I will later merge with the tips and tutorials thread.

Fellow "seasoned" customizers please feel free to add your 2 cents or let us know your thoughts on this topic, but as always remember to keep it fun and friendly

As always, it is recommended to use Acrylic paint over enamel. A fellow mod from another forum discovered an excellent blog post on the topic "The Difference Between Acrylic Paint Grades" (for those of you who don't like to follow links I've copied and pasted below )

The Colorful Truth About the Difference Between Acrylic Paint Grades

(Drum Roll Please…)

If you’ll recall from where we left off last time; we have pigment and we have binder. Here comes the answer you’ve been kept in suspense over. The primary factor in different grades of paint is the ratio of pigment to binder.

Binder comes in several differing forms, some runny, some thick, some sticky, and some jelly-like. Regardless the type, binder is generally much less expensive than pigment which is often derived from pure and sometimes rare elements. Thus paint with more binder and less pigment in the mix will be less expensive to manufacture than one with a lot of pigment, and less binder.

This ratio is called the Pigment Load.
Lower grade paints have a low pigment load, which makes them less expensive. The very best grades of paint have a high pigment load ratio. This applies to virtually all paints on the planet—watercolors, acrylics, oils, exterior paint, you name it!

Though there are varying costs for the different types of binder, delivery and storage method; the biggest difference between ‘cheap’ and quality paint -between inexpensive and quite costly, is usually all about the pigment load ratio. Of course at the upper end, the source, rarity, purity and type of pigment become primary factors in the price of the paint.

Acrylic Paint Grades

Artist (grade) acrylics are designed for painting on canvas, board, paper, panels, and other prepared surfaces. They are highly pigmented and and generally of a paste consistency thus preserving brush strokes. They can be used with a variety of painting techniques, including impasto and knife painting.

Iridescent, pearlescent, interference, and metallic (grade) acrylics mix conventional pigments with powdered mica (aluminum silicate) or bronze to achieve amazing effects. Colors have shimmering and reflective characteristics, depending on the coarseness or fineness of the powder added. Iridescent colors are used in both fine arts as well as crafts.

Student (grade) acrylics have working characteristics similar to the higher-grade artist acrylics, but with lower pigment concentrations, less expensive formulas, and a smaller range of colors. More expensive pigments are generally imitated by hues; that is, use of less pure mixtures of pigment to achieve the look of the purer high grade pigmenting elements. Student grade acrylic colors though formulated to be mixed; will have expectedly lower color strength. Hues also may not provide the same exact mixing characteristics of full-strength colors.

Incidentally, there’s no reason at all to spend the extra shekels on the higher-grade paints until you’ve used student grade to ‘flesh out’ an image on your prepared surface. It generally takes several applications to fill in for the absent pigment anyway, so if you like the way a piece is turning out you can always get the artist grade to go over and complete the painting.

Fluid (grade) acrylics have high pigment concentrations, but lower viscosity (so they’re thinner) than artist acrylics. They mix easily into almost any acrylic mediums. Fluid acrylics can be used in achieving a watercolor-like technique. They are also an excellent choice when working with a sprayer or airbrush. Mix them into heavy gels for impasto techniques. They also find many uses among crafters.

Gouache (grade) acrylic is both a fluid acrylic and a craft acrylic. Like traditional gouache, it is opaque and dries to a matte finish. Unlike traditional gouache, it uses an acrylic polymer binder that is water-resistant when dry. Like craft acrylics, it adheres well to many surfaces. This makes it a favorite in decorative and folk art techniques.

Craft (grade) acrylics can be used on surfaces besides canvas, such as wood, metal, fabrics, and ceramics. They are used in decorative painting techniques and faux finishes, often to decorate ordinary everyday objects.

Scholastic (grade) acrylics use considerably less expensive pigments as well as dyes in formulations that are safe for younger artists, and cost effective for classroom use (i.e. finger painting). The color range is normally limited to common primary and secondary colors, and the actual pigments are unspecified. Because scholastic acrylics use dyes as well as pigments they won’t be very lightfast and so will fade from extended exposure to bright light.

Exterior (grade) acrylic, our last but certainly not least. Although I was kidding about exterior grade acrylic paints earlier they are often used as artistic medium and are available in in several grades or pigment load levels themselves. As is apparent by their name they are formulated to withstand outdoor conditions. Like craft acrylics, they adhere to a variety of surfaces. They are more resistant than other acrylic paint to both water and ultraviolet light. This makes them ideal for architectural accents, murals, outdoor signs, and many faux finishing techniques. Think about it for a moment; exterior acrylic paint is seen more than any other grade of acrylic paint. I’m not speaking of the homeowner’s annual or biannual preventative coat. The murals in public outdoor venues are definitely viewed on a much larger scale than the masterpieces in art museum collections or small galleries.

Did that help clear up any ambiguity regarding the differences in grades of acrylic paint? Hopefully you now have a much better understanding of the differences as well as some creative ideas about how to use the various grades of acrylic based paints. More options to add to the mix when devising the creation of your vision. Enjoy!