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Making Beeswax Impasto Medium for Oil Painting

Beeswax Impasto Medium is a traditional oil painter’s medium that is used to thicken paint. You can buy it ready-prepared or make your own. Vincent Gordon takes us through the steps of how to make it yourself.

The paints at the top are soft and buttery. The paints at the bottom have been mixed with beeswax impasto medium (shown on the right) and are stiffer and will hold sharper edges.


In the late 1500s we first notice a deliberate use of the raised mark and what is considered the first steps towards an impasto style of painting, in the works of Titian and other painters of the Renaissance period. The technique found wider use in the drama of Baroque paintings beginning in the 1600s with works by Rembrandt and other artists of that period. Fast forward then to the late 1800s with the onset of Modern expressive forms of painting and the preoccupation with emotion expressed through surface quality and colour. Impasto painting really begins to establish itself in the works of Van Gogh and then the artists of the Expressionist movement. Since then impasto painting techniques have been widely used by modern and contemporary artists.

impasto medium


Beeswax Impasto Painting Medium

Impasto medium is a paste that is added to oil paint to allow a raised brushmark on the surface. The traditional impasto medium is made with beeswax. It will thicken and stiffen oil paint to retain brush and painting knife marks, extend paint, and add a waxy matt sheen to your colours. It demands a confident and bold approach to mark-making.

The following formula will make a soft, easy to control impasto medium:

Formula

100g Bleached Beeswax pellets
100ml Damar Varnish 5lb cut
200ml Turpentine (rectified, double-distilled or gum)

Natural or bleached beeswax can be used. I would recommend using bleached as it is much paler in colour and will not discolour lighter paint shades in the way that a yellow, natural beeswax will. You should also obtain the beeswax in pellet, granular, or flake form, for ease of use when weighing and dissolving.

The 5lb cut Damar Varnish will act as a strengthening and wetting agent in the formula, helping to prevent the beeswax from drying out and cracking after applying. Damar Varnish 5lb cut can be bought ready-made or see my article How to make Damar Varnish to make your own. The term ‘5 lb cut’ means ‘five pound cut’, ‘lb’ from the Latin standing for ‘pound’, an old abbreviation that is still widely used in the USA among other places and is a designation of the concentration of resin in the varnish.


Method

impasto medium

Any airtight container that can withstand solvents will work.
Shown left to right: Studio Essentials Plastic Screwtop Jar, Studio Glass Bottle, and an empty jam jar.

1. Weigh out the beeswax pellets or granules and place them in a large glass jar, (you will need the lid).

impasto medium

2. In a separate vessel, ie. mixing jug, combine the damar varnish with the turpentine and stir thoroughly. I use an old, unvarnished paintbrush handle for stirring. Avoid brush handles that have been varnished or lacquered with a colour, as these tend to peel and flake after a time and may contaminate your medium.

impasto medium

3. Pour the damar/turps mixture into the jar containing the beeswax.

impasto medium

4. Stir everything together until all the beeswax pellets are fully wetted and the damar/turps mix starts to turn the milky white colour of the beeswax. This change of colour tells you that the turpentine has already started to break down the wax pellets. You may need to stir the mixture for 2 to 3 minutes to achieve this.

5. Place a lid on the jar and leave overnight. Stir again thoroughly on your return the next day, being sure to scrape the sides and bottom of the jar. Repeat this process over 3 to 4 days.

6. The beeswax is fully dissolved when you cannot see any individual pellets remaining whilst stirring, and the mixture is a smooth white paste. It will be thick enough that your stirring implement will stand up in it. Make sure you check the bottom and sides of the jar as these will be the last areas to dissolve.

When you think the medium is ready to use, scoop out some of the impasto medium from the side or bottom of the jar using a painting knife and spread it thinly along the length of a palette knife, a 1-inch wide knife is ideal for this. If the medium looks smooth and lump-free then it is fully dissolved and ready to use. If you see any undissolved wax pellets on the palette knife then you need to stir the mixture again and leave for another day.

making impasto medium

Spreading the medium along a large palette knife is a good way to inspect it to see if the wax is fully dissolved. It should be smooth and free of lumps.


Using Your Beeswax Impasto Medium

Mix the impasto medium with your oil paint on a palette in any quantity, but bear in mind that the more medium you add, the less colour strength you will have as the amount of pigment is then dispersed in a larger amount of material. This also increases the transparency of the mixture. A 50/50 mix of paint and medium is a good place to start, you can then either increase the amount of paint in the mix to bring the colour strength back up or increase the amount of medium to further extend and thicken your mix. Always be patient when mixing a medium with paint on a palette, the more thoroughly they are combined, the more consistent your paint finish will be.

making beeswax impasto medium

A light turquoise paint was mixed from white and Phthalo Turquoise. The left side is neat paint and while it does have body, notice how soft the edges are. The paint on the right side has had impasto paste mixed in to thicken the paint. You can see that it is stiffer while still being creamy. Notice the slight lightening of the colour. The paint will also be more transparent in thin layers.

This formulation of impasto medium is smoother than some other beeswax oil painting mediums. For instance, compare the smoothness of the mixture above to the graininess of the Gamblin Cold Wax Medium mixture below.

Gamblin Cold Wax Medium is a ready-made beeswax medium but it is made with alkyd resin and odourless mineral spirits instead of damar resin and turpentine. Notice how it has a grainier texture when mixed with oil paint. The paint on the left is neat and the paint on the right has been mixed with the Gamblin Cold Wax Medium.


Shelf-life, Drying time, Varnish, Stability

Over time your medium will stiffen in the jar, so it is best used within six months, though if the jar is well-sealed I have had it last much longer. If the medium has thickened but is still usable, try adding very small amounts of turpentine to your paint/medium mix on the palette whilst blending to loosen it up.

The drying time of your paint when mixed with impasto medium will depend on how thickly it is applied and to what substrate. Low ridges of say 2mm applied to a canvas support should be dry in around two weeks. Thicker applications will skin-over in a similar amount of time, but may remain soft underneath this skin for several months. Eventually, after at least six months, the paint and wax mixture will dry hard but remain flexible regardless of the paint-to-medium ratio.

If you wish to alter the sheen of your fully-dried impasto painting, then applying a varnish is a possibility. A spray varnish is a good choice because a brushed-on varnish may pool around the ridges of raised areas of paint, which may then run or create an uneven varnish finish. If you do use brushed-on varnish, then during varnishing, carefully check all the raised areas of paint and gently brush out any pools of varnish that may have accumulated.

If you wonder about wax being sensitive to heat, it is reassuring to know that the dried surface of your painting will be stable. The melting point of bleached beeswax is around 65°C, and even higher when blended with oil paint, so your painting will not be vulnerable to the heat of normal environmental conditions.

Impasto mediums can help you achieve quite high ridges when painting with a knife.


Ingredients and Equipment at Jackson’s


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