Page 24 - Artist Materials Advisor

Here is a typical recipe to make gouache paint. Gouache consists of water, pigment, and gum binder, the same as watercolor paint. The difference is primarily the addition of a white extender, which creates an opaque water-based paint.

The ground is the paint layer applied to the support to prepare it to receive paint. Paint­ing grounds have several functions; the most essential is to provide a surface favorable to paint application. Grounds also change the absorbency of the support, reduce or enhance its texture, provide a different texture entirely, and create a surface that forms a good bond between the support and the paint layer. The ground is crucial to the durability of the painting. De Mayerne noted as early as the 17th century that quality materials were as essential to the ground layer as to the paint layer.

To create a fresco, it is necessary to understand the process. In buon or true fresco, you paint with pure pigments on wet lime plaster. As the plaster cures, a layer of crystal forms over the pigment, locking it into the surface. The author, assistant to Dego Rivera, discusses the brief history of fresco painting techniques.

There’s a bewildering array of drying oils for oil painting. Where do all the different drying oils come from? How are they different? And how do you choose the right one for your painting?

Gel painting mediums come in a variety of thicknesses and properties, but their primary purpose is to change the consistency or appearance of paint. Think of gel medium as transparent paint so that when added to oil colors, it diminishes the opacity of the color while helping to maintain its consistency. Gel mediums increase the transparency of oil colors without making the paint more fluid, such as when adding drying oil to increase the transparency of a color. This is advantageous when you want a transparent layer of color without making the paint runny.

Formulas for varnishes and mediums call for measurements that are often confusing for artists. For example, in his formula for a glazing medium, Ralph Mayer calls for a “5-pound cut” of dammar (or damar) varnish. How do you know what is a 5-pound cut?

The term balsam has been used to designate the resinous exudate from trees of the order Coniferae, which have also been called resin or turpentine. Balsam is a soft, semi-liquid consisting of terpenes associated with bodies of resinous properties. The balsams most used in varnishes or as paint mediums are Larch balsam (a component of Venice turpentine), Strasbourg turpentine, Canada balsam, and copaiba balsam. Balsams flow easily on a surface and give a lustrous, pleasing quality when applied. However, unless a harder resin is mixed with them, they deteriorate quickly. Here are several formulas incorporating balsams.

The term ‘flake white’ originated from the fact that when basic lead carbonate is made according to the old Dutch method or ‘stack process,’ it falls off the metallic pieces of lead as ‘flakes.’ This is not the case when lead white is made according to modern processes, which is the pigment type used by all artists’ paint manufacturers today.

Congo copal is no longer available commercially (at least as it was available in commerce formerly), because the suppliers have long stopped trading due to strife in Africa since the last quarter of the 20th century. Trade of Congo copal was once controlled by the Belgian government, but as this region of Africa gained independence and the demand for copal resins diminished during the last half of the 20th century, the commerce of Congo copal has all but ceased.

Ackermann’s Superfine Water Colours were prepared and sold at Rudolph Ackermann’s shop, The Repository of Arts at 101 Strand in London, and also sold through print and booksellers in Great Britain. He published a list of watercolor cakes that appeared in 1801 and was appended to A Treatise on Ackermann’s Superfine Water Colours.