Choosing Gels, Mediums & Pastes

I often get emails asking about the differences between acrylic gels, mediums and pastes.
First, it helps to understand a general principle behind all paint and painting products.
All colored paints are made with basically two components: pigment - for color, and binder (also called medium, vehicle, and in the case of acrylic paints - polymer) which turns the pigment into a usable paint.

Any other product is usually some form of plain binder without any pigment, and is created to help customize your paint. These are used to change some characteristic of the paint itself, or to change a quality of your painting surface. The gels, mediums and pastes all fit in this category. Let’s start with gels and mediums. Gels are basically thick, while mediums are thin and pourable. Acrylic binder is naturally very thin and pourable. Most people assume acrylic is naturally thick – but it’s not. The thin quality of acrylic or polymer is not made by adding water or diluting. It just is naturally thin. So the gels and thick acrylic paints have thickeners added, while mediums have less thickener, and in the case of Golden’s specialty mediums, have none. (Golden’s specialty mediums are labeled GAC100, GAC200, etc. The GAC stands for Golden Artist Colors). All gloss gels and mediums are clear, while matte products have a finely ground white powder added to them, so they are often slightly cloudy or translucent. Pastes are thick and opaque.

Let’s look at how we could use them:

To change the consistency of a paint mixture you would add up to 30% medium to make it thinner, gel to make it thicker, and a specialty medium (GAC100 or GAC500) to eliminate texture altogether.

To make a colored paint more transparent you would make a mixture of paint with binder, but much more binder than color – about 90% binder and 10% color. You would add gloss gel (if you like texture) or a gloss medium (if you want minimal texture). For a very smooth enamel look use GAC100 or GAC500.

To make any color opaque you would add paste.

To cover over an area in your painting you would apply paste to the area (or white paint).

To create a textured ground use a gel with a knife. Gels have lots of thickener - and you have a choice of varying amounts of thickeners in the soft gel, regular gel, heavy gel and extra heavy gel (which has the most and therefore is the stiffest in handling).

To pour acrylic you would think of using a medium, since these are all pourable. However, there are 2 gel exceptions that are better for pouring: Self-Leveling Gel and Clear Tar Gel are both gels, but are pourable. I add small amounts of water to either of these, and pour over a painting to create a clear, glossy “surfboard” finish. I use minimal handling with these, in other words, I don’t use a brush or knife, but tilt the surface to move the “pour”. GAC800 is also a great pouring medium, and is the easiest to use since it isn’t as finicky as the other gels I mentioned, and will give the smoothest surface as it won’t crevice in fast drying climates – like out here in New Mexico where I live. Adding color is an option to any of these ideas.

My book, Acrylic Revolution, has over 100 acrylic painting techniques using gels, mediums and pastes. Click here to read more and/or order the book at a discount from Amazon.

Color Control with Acrylic

Perhaps you have noticed that as your acrylic painting dries, the colors change. They get darker. Actually what is happening is the acrylic paint appears lighter while it is wet. All paints are made of two basic components, pigment (which looks like colored dirt before it is used in the paint) and binder, which holds the pigment particles together and turns them into a usable paint form. Other terms for binder are vehicle or medium.

Polymer or acrylic is the medium/vehicle/binder for acrylic paint. It is white when wet, but dries totally clear and glossy. There are no white additives in the binder, but the white appearance is due to a microscopic bubbling that disappears when dry. So when you paint with acrylic it is lighter when wet, due to this whitish phenomenon. Then when the paint is dry, this binder turns clear and the color turns into its true hue. Here is an interesting comparison from music that helps me when I paint. Musical scales consist of the same note patterns, but they change in octaves. So just like I would transpose one octave into another, I paint about 10-15% lighter then what I want it to look like when dry. In other words, I go up one octave in value when I paint. The more gels or mediums you add to your paint color the greater the difference between it’s hue when wet as opposed to dry.

If this is bothersome to you here are some other options. If you don’t mind working with the paint a bit thick, then try adding at least 50% Golden’s Light Molding Paste to your paints. The paste is white when wet, and stays white when dry, so there is no change (or at least very slight) in color between wet and dry.

Another option if you don’t like the hue change, and don’t want to work with pastes, is to use the acrylic in washes like watercolor. This technique is best accomplished using an absorbent surface such as watercolor paper, or some of the unusual acrylic grounds that are available (like Pumice Gel, Light Molding Paste, and Absorbent Ground). Add at least 50% water to your paint. After painting with these diluted washes, the color stays pretty much the same hue when dry. This is because most of the acrylic binder has been diminished with the addition of water.




Pictured here is one of my paintings that uses all three techniques (1) acrylic painted lighter while wet, (2) washes on absorbent surfaces and (3) adding Light Molding Paste to the paint)



My new book, Acrylic Revolution, North Light Books, contains over 100 techniques including step by step detailed descriptions of the above methods. Please click here for purchase information.

The Sensuous Paint Skin

One of my favorite painting teachers, Phyllis Bramson, had a great analogy for painters, by comparing the paint to human skin. When a painting is finished the paint layers all cure together to form a tactile paint surface. This surface, according to Bramson, can be compared to skin. It can be thick and palpable like a baby’s skin, or thin and transparent, like the skin of someone elderly. When I first heard this it confused me, because at that time I was a new mother. My son was only 2 years old, and his skin was very transparent, not thick and palpable. I could see veins on his face just below the skin’s surface. But, hey, it was a cool analogy, and I decided to stop trying to figure it out, and just use it.

So now when I paint I often take the time to just look at the applied paint, and think about how it makes me feel. Just the paint. Not the images, colors, composition…but just the paint. If it’s thick and textured it feels tactile or sensual. If applied thinly, then I want it to feel silky, soft, veiled, vaporous. While wandering in galleries looking at art, I will search out paintings that intrigue me. Maybe I like the colors, or imagery, and will walk up really close to it. When I get right up there nose to paint, I want to feel the paint. If it looks too thin and skimpy I lose interest.

Here in Santa Fe we are lucky enough to have a Georgia O’Keeffe Museum. Her work is a perfect example of what I call “the sensuous paint skin”. (Please note that you can’t see the true nature of her painting surfaces in a photograph, only in person). In almost every oil painting of hers, there are two contrasting ways of handling the paint. Some areas are barely covered by a thin layer of paint, and you can still see the texture of the canvas coming through, while other areas use heavy impasto (brushy or knife applied texture) showing off her luscious brush strokes.

Just to clarify, there are thin applications of paint that I feel can still look sensuous. A powerful painting is created when the artist allows the medium itself to speak through the work. And what better way to let it speak then through it’s own physicality, by expressing itself through a tactile quality in the final surface.

Going Beyond Technique

The learning curve for most artists generally takes a similar path, which I see consisting of 2 parts. The first part is mastering technique. Not all techniques in all mediums, but the ones that will best suit the artists needs. The technique is mastered when the artist has enough tools to say what they want to say. Then comes part 2. This is a key point where the artist rises above technique, and the message or content or voice of the artist takes precedent. Here it gets tricky because a successful work of art contains not only the voice of the artist but the voice of the medium as well. The artist must create a balance between mastery and surrender. Mastery of the technique, while surrendering to the materials and message, as well as being a conduit to the collective energies/concerns of the times.

As a teacher I often see a tough spot happening between parts 1 and 2. This is the “leaping off” step. Sometimes students will keep taking class after class long after they have enough technique, but it’s a bit scary at that point to realize you have enough technique and then to use those techniques to say what you want to say. My suggestion is that students take a few technique classes, then take a year off with no classes and no teachers to just paint on their own. From then on sign up for a short workshop once a year to add something new, get reinspired.

I recently received a comment regarding my book, Acrylic Revolution, wishing that more of the examples in the book were finished paintings, and here is a good opportunity to add some clarity to my intent. This book is a collection of techniques. My intent in writing this book was to inspire artists to make that leap from part 1 to part 2, and to create their own unique style by combining techniques. To do this I decided to give final examples for each of the techniques but only going as far as a technique can go without becoming a painting. I put finished paintings at the gallery at the end of the book to show that powerful paintings are a combination of many techniques. It is this combining that encourages creating your own style. The techniques are purposefully left in a state full of potential, just for those purposes, to get your own creative juices flowing – not to imitate.

Opaque Painting Techniques Using Acrylic

Using contrasts or opposites is an important painting tool. Pairing warm with cool colors, or hard edges with soft, or simple spaces with complex ones, adds intrigue, focus and power to the image. Since I like to use glazes and transparent layering in my work, an essential contrasting technique then, is the use of opaque painted areas. Not all colors are opaque right out of the tube. The newer colors, which often have unusual names like Phthalo or Quinacridone, are naturally transparent. The more common colors such as Yellow Ochre, Burnt Sienna and Cadmiums are naturally opaque. (More information about pigment differences is included in my new book, Acrylic Revolution.) To paint opaquely, I start my painting session by adding a large lump of acrylic Molding Paste in the middle of my palette. Pastes in general are opaque, and will whiten colors as well as thicken the textural quality. To the paste, I add about 15% retarder and some water, mixing thoroughly, and keeping the paste mixture in a close clump on the palette to keep it staying wet longer. As I paint, I make smaller mixtures on the palette using 1 part colored acrylic paint to1 part of the paste mixture. I usually apply it with a painting knife. A painting I recently finished, called Koi Pond, uses this acrylic technique, using the paste mixtures all applied with a knife. My paintings currently on exhibit in Santa Fe use a combination of the opaque pastes with transparent glazes.

Glazes with Texture

Glazing is a technique commonly used in many mediums such as oil and acrylic to create transparent layers of color. Since acrylic can be used thickly with no cracking or adhesion problems, it also has the benefit of offering some more unusual painting applications. By using a thick acrylic gel, and adding this into regular acrylic colored paint, you can create a thick but transparent subtly colored mixture. Apply this mixture over previously applied dried and painted layers using a variety of application tools to create some unusual effects. There are many acrylic gels available for purchase. Gels are actually an acrylic medium, with the addition of thickeners, to create a thick or stiff acrylic that can be easily manipulated in a sculpting manner. I like using painting knives, rubber shaper tools, fingers, sticks, etc, as well as brushes to get my textural effects. The main point to keep in mind, is to use a clear acrylic gel to get the transparency, instead of an opaque paste. And to use a small amount of color into a larger amount of gel. I like to use a 1:10 ratio of color to gel.

The Best Time to Use Glazes

A glaze can be considered a delicate layer of color. Delicate because it is so subtle and transparent. Therefore, a glaze is best used on top of a stronger base color. A common Old Master's Technique used a grisaille, meaning grays, which is an underpainting composed of dark and light paint colors using combinations of grays or neutrals. This "gray" underpainting allows the artist to concentrate on patterns of dark and light and general composition concepts, without thinking of color just yet. When this grisaille, or first layer of paint is dry, the artist applies glazes of color over the grays, shifting the hue, and turning the gray painting into a colored painting containing a variety of values or tones. There are many ways to create underpaintings, and the use of grisaille tends to evoke an Old Master's realism. As an abstract artist, I like to apply bright opaque areas of color as my underpainting and then use glazes over those to shift them in tone and hue. This contemporary use of glazing has many advantages, including creating the illusion of solid form from the previously flat underpainted color shapes. Here is my favorite example of when to use a glaze. Let's say you were commissioned to paint a realistic portrait. After painting for quite awhile you finish the portrait in all its full gloried detail. It's fabulous! However, the client upon seeing it feels the skin tone is a bit too yellow. To repaint the portrait would take a long time, and feel like a waste of time. Instead mix a glaze of violet (yellow's opposite or complementary color) to tone it down. Apply a single even layer of this violet glaze over the entire portrait. If the glaze is too strong the skin tone in the portrait will turn violet. But if the transparency is correct, the yellow will get just enough violet on top to neutralize it towards a more acceptable skin tone. I like to mix a glaze and then test it on top of a small area first. I keep playing with it and testing it until it's just right before applying it all over.

How to Create Glazes Using Acrylic Paints.

A glaze is a transparent and subtle color application. Glazing in acrylic is best accomplished by using a slow drying medium. You can make your own slow drying medium by adding an acrylic additive called retarder to any regular acrylic gloss medium. Add up to 15% retarder to the medium. You can also use Golden's Acrylic Glazing Medium, which already contains a good proportion of retarder and medium. I often add a small amount of water to this retarder & medium mixture to help eliminate brush strokes and to ease the application. To this slow drying medium, add a very small amount of colored paint to make a colored glaze. I like to use about 1 part paint to 10 parts medium. Mix well with a knife. This mixture of medium, retarder, water and colored paint is now a glaze. Apply the glaze using a very soft brush, over an area you want to shift in color. Keep the glaze application very thin by wiping off excess glaze from your brush onto paper towels. Work quickly, and do not go back over an area once it starts to get tacky. This layer now needs to dry to work any further, or to add a new layer. When working on several layers, put a fan right next to the artwork to quick dry the freshly applied layer of glaze. To see examples of paintings using acrylic glazes go to my painting page and/or acrylic techniques page. For more information on glazes and other acrylic painting techniques see Nancy Reyner's newly released book, Acrylic Revolution, North Light Books.

Calendar of Events
Acrylic workshops, lectures and book signings for Nancy Reyner have just been scheduled in Scottsdale, Arizona and Silver City, New Mexico. For details visit my painting workshops page.


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