Frequently Asked Questions

On this page I will be listing FAQ that need to be answered. If you have a question about oil painting, send the contact form to us and we will post your question and answer on this page.

What is oil paint made of?

Oil paint is made up of powdered pigments coming from organic and man-made substances. These pigments are mixed with an oil (binder or vehicle) to dilute them to a consistency suitable for painting. The paints are made in various qualities or grades. The cheaper or inexpensive paints are usually ground into an oil that is known to darken with time and exposure to light. The better expensive permanent types of paint used by professional artist are ground into the best oils. They have the finest stable and balanced pigments.

The organic oil paint pigments come from different types of metals and minerals. Some of the blue colours come from copper. Cobalt is a pliable, soft metal until it is heat treated. The processing of the metal ingredients in the paints increase the price of the paint.

The man-made substances used for some pigments are created from different metals such as the cadmiums. Other man-made metal is the titanium pigment.

The paint pigment is ground together with a binder such as linseed oil, other oils are used depending on the pigment. Bees wax can be added and driers and stabilizers.

When you look at the label on the tube of paint the name of the pigment used and the pigment number is listed. For example PBr7 - PBr stands for pigment brown, PY pigment yellow etc. The label will also tell you about the vehicle or binder the paint has been made with. This binder or vehicle is usually linseed oil. Sometimes safflower oil is used for light colours.

What is light fastness?

Because UV (ultra-violet) light oxidized the colour off with time, some paints are less likely to fade. This is under the "light fastness" rating the manufacturer assigns to a colour. It also relates to the "permanence" of a colour. This rating is given to oil paints with regard to their quality and grade of paint. The lower the rating number, the more fading from the UV light under normal conditions. In addition, the type and quality of vehicle or binder in the pigment would affect the light fastness rating. For a cheaper paint there would be a higher incident of fading compared with a more expensive brand.

How do you determine if a paint is opaque or transparent?

Usually it will say on the label of the paint tube. But if it doesn't then you can check by putting a dark line on a piece of white card, use a brush to put a thin layer of paint over this line. If you can see the line; it is transparent. If you can not see the line the paint is opaque. If the line is indistinct but visible it is translucent or semi-opaque.After you have been painting awhile, you will learn which colours are transparent and which are opaque and semi-opaque.

Why do some paints dry faster than others?

The earth colours dry faster which are:

Burnt Umber

Burnt Sienna

Raw Umber

Raw Sienna

Light Red

Mars Red

Mars Violet

Mars Orange

are all made using iron oxide. It is the metal that has corroded and iron oxide (rust) is what is left. These colours are often used at the beginning of a painting.

The slower drying colours are:

Titanium White

Zinc White

Alizarin Crimson

Some yellows

Green Earth

Ivory Black

These are often used toward the end of a painting. This is the principle of fat over lean in practice.

What are the differences between oil paints and acrylic paints?

The biggest difference is with traditional oil paints you use a medium or solvent to thin the paint with. With acrylic paints you use water to thin the paint with. But today you can get water soluble oil paint. This water soluble oil paint uses water instead of solvent or linseed oil to thin the paint with. Another difference is the drying time between acrylic and oil paints. Acrylic paint dries alot faster than oil paint. You can slow the drying time in acrylic paint by adding a medium called a retarder. You have to learn to paint alot quicker with acrylic paints to accommodate the drying time. The drying time in oil paints is alot slower (depends on the colours too). Another difference is acrylic paints have no smell as opposed to the traditional oil paints thinned with solvents.

What are the similarities between oil paints and acrylic paints?

The thick consistency of the paint that allows many different painting techniques. You can use virtually all the same painting techniques with both types of paint. The painting order of using your dark colours first then gradually using the lighter colours after is the same. (dark to light) This is the opposite with watercolour. You paint on an easel or some sort of prop.

What does the "fat over lean" rule mean?

When you paint with oils you need to start with thin paint by using a medium to thin it or make it more fluid. The oil paint is very thick straight out of the tube. By thinning the paint with a medium, this give the paint a more flexible feel to it. As you build up your paint layers you will use less medium; thus your paint will be thicker and less fluid or less flexible. By going by this rule "fat over lean" you will avoid the "cracking" that can occur due to the thinner paint drying quicker than the thicker paint underneath it.

How do I change something in my painting?

You may have painted a picture and decide you don't like something about it and want to change it. You may just want to move a tree or eliminate a rock or bush from your painting. If the painting is still wet you can scrape off the area you want to change. The palette knife is a good tool for this job. If you want to wipe out the area completely you can use a rag dipped in solvent and this will remove most of the paint in the area you want to change. If the painting is dry then you will have to remove all the rough areas by using sand paper and then paint over the entire painting. I have found it is a good idea to keep all your old paintings and then you can look back and see your progress.

How do you know when a painting is done?

The answer to this question for me is when there is no longer anything that is annoying me about the painting.

How does oil paint dry?

Oil paint dries by a process of oxidation rather than absorption and evaporation. Drying by oxidation means that the oils change from a liquid to a solid state when the oil molecules absorb oxygen into their polymer chain. When uncured oil paint gets buried by overpainting, its oxygen access is restricted. The surface layer which is exposed will dry first, and the deep underlayers will take much longer to oxidize. It can take years for a painting that has very thick paint to dry completely.