Surface preparations are used to seal, prime and add tooth (for color adhesion) to all surfaces such
as canvas, wood, paper and metal.
The most commonly known and used medium is gesso. Gesso comes in different viscosities from heavy gesso that has the ability to hold sculptural shape to thin gesso that is a gentle primer for fine art work. Gesso comes in white, clear or black.
Within the painting category, there are several different types of products you would use in
addition to the color itself. They are Fluid Mediums, Gel Mediums, Additives, and Texture
Gels. In general when it comes to thinning acrylics, the only 'rule' is to not mix acrylic paint with more than 50 per cent water. Any more than this and it may loose its adhesive qualities and peel off at some stage, or lift when you paint over it.
You can mix in as much acrylic medium (glazing, texture paste, etc) as you like because it's got the acrylic resin in it that acts as the 'glue' that makes the paint 'stick'.
Fluid Mediums reduce viscosity of heavier paints and gels, tend to self-level and
do not retain brushstrokes. Fluid Mediums modify acrylic paints in a variety of
ways and contain acrylic resins to maintain or enhance adhesion and durability.
Use when maximum transparency is required to add luminosity and depth to your projects. This
fluid medium can be used to create brilliant glazes when mixed with transparent color. Glazing
Medium dries quickly for rapid layering and tends to minimize or eliminate brush strokes.
A classic medium used to give fluidity to delicate brushwork or to act as a low sheen
adhesive for collage. This medium has a creamy consistency and is great with opaque
This medium is used to extend the “open” time of acrylics by more than 40%, giving you an opportunity to really work the paint to enhance color blending.
On the opposite end of the spectrum from Fluid Mediums, Gel Mediums add
body to thinner paint as well as extending color volume and adding transparency. Gels mediums can also add “open time” as they tend to dry slower than thinner paint films.
Excellent for retaining brush marks while slowing the drying time and adding body to the
paint. Excellent for transferring printed images.
Gloss/Matte Heavy Gel
A very thick gel medium that extends working time and increases brilliance and transparency. Mix with acrylic paint to increase body and get an oil paint like look that holds brush or palette knife marks. Ideal for creating collages with heavier objects.
A very thick, matte, opaque preparation of marble dust and polymer emulsion used to build
heavy textures on rigid surfaces. This product handles like clay and dries to a very hard
stone-like surface. Can be mixed with acrylic color or overpainted when dry. Great for sculptural
Fluid Medium Effects
Enhances blending, workability, and adhesion of acrylic colors for painting directly on fabric or unprimed canvas. Reduces dry paint stiffness. No heat setting required.
Adds richness to acrylic colors by creating a metallic/pearlescent effect. Dries translucent
and will not oxidize. Can add shimmer or sparkle to a picture even in the smallest amount.
A pre-filtered, ready-to-use medium that easily thins any acrylic to the right consistency for
spray application. An excellent choice for color washes and watercolor techniques when used
with acrylic colors.
Texture Gels contain particles that produce a variety of unique textural and dimensional
effects. They may be mixed with acrylic colors, other mediums, or used on their own.
White Opaque Flakes
A heavy, coarse gel containing irregular sized and shaped white opaque flakes. May be used
to create foliage effects in landscapes by mixing with opaque color or glazing over when dry. Has a similar effect of snow flakes or coconut flakes.
A medium body gel that contains clear round plastic beads and dries to a semi-gloss surface. Perfect for creating a “bubbly” but smooth texture that can be dramatic when mixed with color.
Additives allow you to adjust the chemistry (and as a result the working properties) of
acrylic paint. They can be used to increase the flow, the opacity, or the thickness, and more.
An excellent choice when working in low humidity, or whenever increased workability and
blending time of acrylic paints and mediums is desired.
Varnishes are applied over a completed piece of work to change or unify the surface sheen
and protect the painted surface from the environment and ultraviolet light.
There are many misconceptions about whether or not it is necessary to varnish an acrylic project. As a general rule, you should always varnish your acrylic work when possible. Varnishes are applied over dry paint films and serve several purposes. Their first and most important function is to protect the project surface from the environment and protect the pigments from ultraviolet light.
In general there are two qualities of these materials: artist quality and craft quality. The artist's materials are usually more expensive and come in larger containers. If you are a beginner I recommend start with craft supplies and see what you like. Both versions can be bought in most craft chains and stores.
Please tell me if you found this post useful!
Don't miss out! Keep up with all the crafty goodness by subscribing to the Einat Kessler creative newsletter