Dawn Jordan shares several ways to prepare a MDF board ready for oil painting.
The choice of surface you paint on can create very different effects in a painting. The preparation of the surface also can create such a difference to the final outcome of the painting. In this article I am concentrating on MDF board.
Generally, the thicknesses I use are 3mm, 4mm or 6mm board. Obviously the thinner the board, the lighter in weight, which is an important consideration when painting en plein air, either on holiday or just to keep the weight down in your back pack when painting for the whole day.
I do find 4mm MDF difficult to source, but your local builder’s merchant is a good place to start and they should be able to cut the board into the sizes required.
I tend to prepare a lot of boards at once, creating a variety of textures, (rough, smooth etc) and using different coloured grounds, meaning I have a ready supply to hand to suit every occasion when going out to paint.
Preparation of MDF Board
There are various ways of priming and preparing a board for painting including using an oil primer or an acrylic gesso primer. Here I concentrate mainly on the acrylic gesso method:
- Apply two to three coats of acrylic gesso using a cheap brush or a roller, depending on the finish you desire. If you are looking for a very smooth finish the gesso can be finished with sand paper, however, I tend to like the brush marks to show so use a stiff decorators brush. For smaller boards I use a 1” brush, brushing in different directions
- The final coat can be finished in different ways depending on the effect you want.
- Use just gesso to give a white finish
- Add some acrylic paint to the gesso to give you a coloured ground. There are also a limited variety of coloured gesso on the market.
- Use a texture paste for a rougher finish. A textured ground is good to enhance broken brush work which gives a looser feel to the painting. There are various texture pastes on the market but Holbein do a white acrylic gesso in a coarse texture which gives a fine sand texture. They also make this in a clear acrylic gesso coarse texture which you can mix with acrylic colour to give a tinted ground. I sometimes use a mix of one part Polyfilla (powder) to three parts gesso and apply with a stiff 1” decorators brush leaving the brush marks visible. Depending on how short (absorbant) you want your ground, you may wish to apply the texture coat as the second layer and then a final coat of gesso on top.
- Short grounds - A ‘short’ ground is more absorbent and absorbs the oil from the paint which causes the paint to dry more quickly which is ideal for plein air or alla prima painting. A little chalk (whiting) can be added to the gesso if you require a particularly short ground. ‘Long’ grounds give a glossier look to the painting.
Dusk at Topsham, oil on board with warm burnt sienna ground, (20x25cm)
A coloured ground removes the glaring whiteness of the board and somehow takes away the fear of making that first brush mark. It also makes it easier to judge the values, as a white ground makes darks look darker.
White grounds were traditionally used to create maximum luminosity when using a glazing technique (see Tulips, below).
Tulips, oil on board, painted on a white ground to ensure luminosity in the flowers, (25x25cm)
Different coloured grounds can set the mood and produce different effects in the finished painting. In certain cases, you may want to allow some of the ground to show through in the final painting as this creates unity and depth in your painting.
It is worth experimenting with both warm and cool grounds. Examples of warm grounds would be a burnt sienna (see Dusk at Topsham, above), burnt sienna with a tiny touch of ultramarine, raw sienna or a yellow ochre ground. An example of a cooler ground would be ultramarine with a tiny touch of burnt sienna to produce a cool grey (see Tide Out St. Ives, below).
There are various rules as to which coloured ground to use, but ultimately it comes down to personal choice. One rule is to use a warm ground for a painting with predominantly cool hues or a cool ground for a painting with predominantly warm hues. Another rule is to use a complementary colour for the ground to the predominant hue in the final painting.
The choices for coloured grounds are a turpsy wash or mixing acrylic colour with the last coat of gesso.
Tide Out St Ives, oil on board, painted on a cool grey ground, (20x25cm)
Apply the chosen oil colour, diluted with odourless mineral spirits, using a brush or rag. If it looks too bright or too dark you can rag it back, this will also help to dry the surface. This method allows the luminosity of the white of the gessoed board to penetrate through to subsequent translucent oil layers.
An advantage of using a turpsy wash is that the wipe out, or subtractive method, can be used for preserving highlights and lighter tones in the painting.
Coloured acrylic added to the final gesso layer or applied separately from the gesso
This method enables you to prepare different coloured boards in advance, leaving a dry surface to paint on, which is an advantage when painting plein air or alla prima (wet on wet). It is handy to have a choice of different coloured grounds to suit the various subjects you may want to paint.