Hints, Tips & Techniques for Oil - Mediums
Painting with oil colour almost always involves the use of Mediums and Oils in order to to further control the colour, prevent overthinning (see also solvents) and maintain the flexibility of the paint film (fat over lean).
At Winsor & Newton we can separate our mediums into four categories:
Linseed Oils
Oil Mediums
Fast Drying Mediums and
Water Mixable Mediums
Below you will find an explanation of how mediums are used and an insight into the effects that you can create with them.
Working with oil colour is a skill that needs to be learnt and in this section we will also explain a few of the oil colour rules such as oiling out, how to combine different mediums, fat over lean and why varnishes should never be used as mediums.
Oil mediums in use
Linseed Oils
Linseed oil is the traditional medium, as it is the binder for most oil colours. Generally oils dilute the colour, increasing gloss and transparency and are used in combination with solvents. The consistency, colour and drying time of linseed oil can be varied by different processing.
Click on the links to find out more about each individual product.
Back to top
Oil Mediums
Oil mediums are ready made mixtures of particularly suitable linseed oils with solvents. They can be used as general purpuse mediums and can be used directly for oiling out.
Click on the link to find out more about each individual product.
Back to top
Fast drying mediums
Modern resins called alkyds are used to make fast drying mediums for oil painting. These are extremely popular because they generally halve the drying times of the colours.
Click on the link to find out more about each individual product.
Liquin family
| Liquin Effects |
|
|
|
 Liquin Original effect |
|
 Liquin Fine Detail effect |
|
 Liquin Light Gel effect |
|
 Liquin Impasto effect |
|
Back to top
Water mixable mediums
Water mixable mediums are available for use with Artisan Water Mixable Oil Colours. These dedicated mediums ensure that all the traditional oil colour techniques can be achieved without the use of turpentine or white spirit (mineral spirits). In addition, all Artisan bottles are easy to open as they do not require child resistant caps.
They include:
Artisan mediums family
Back to top
Combining different mediums
All the conventional mediums can be mixed. However, the structure of the painting is under less stress in the long term if mixtures are avoided.
We recommend Water Mixable Mediums to be used exclusively with Artisan colours in order to benefit from the use of water instead of solvents.
Back to top
Not using varnishes as mediums
Picture varnishes are not recommended as constituent parts of mediums because of their resoluble nature. Neither should they be used as intermediate layers in oil paintings.
Back to top
Oil Painting Rules
When painting with oil colour, artists must adhere to three conventional oil painting rules:
- Fat over lean - (see explanation below). When oil painting in layers, each successive layer must be more flexible than the one underneath. This rule is maintained by adding more medium to each successive layer.
- Thick over thin - Thick layers of oil colour are best applied over thin under layers. Thin layers on impasto paintings are likely to crack.
- Slow vs. fast drying colour - Slow drying colours should not form continuous under layers as any faster drying layers on top may crack.
Back to top
Oil Painting Techniques and Effects
Artists can create a multitude of painting effects with the use of mediums. Below are a few illustrations which explain how they work and hopefully inspire you to try them out.
 |
Glazing
Glazing is the build up of layers of transparent or semi trasnparent colour over dry underlayers. It is a lengthy technique where the effects in oil are unmatched when compared to other media. Liquin original is an excellent glazing medium and will reduce brushmarks. |
 |
Scumbling
Loosely brush a thin film of opaque or semi-opaque colour over your underpainting. This may actually show through in places and can retain an important influence on the surface appearance of the painting. Liquin can be used to thin the colour or if you prefer a thick texture, use Liquin Impasto or Liquin Oleopasto |
 |
Stipple Effect
A bristle brush and thick viscous colour can create a "stipple" texture. Tube colour alone will work well or colour mixed with Liquin Oleopasto. |
 |
S'graffito
"S'graffito", the technique of scratching into a wet oil film, can be done with the pointed end of a brush, painting knife or any scraping device.
It is effective in defining outlines or details for expressive effects. If you want more time for scraping back the colour you can slow the drying by using Refined Linseed Oil or Artists' Painting Medium with the colours.
|
 |
Impasto
This is the technique of applying paint thickly, so that the brush strokes are plainly visible and create a textured effect.
Liquin Oleopasto will add texture and increase the transparency. For thick impasto, build the texture in several layers allowing each to dry first.
|
 |
Underpainting
Many artists complete the underpainting ofa project in faster drying colour (such as Griffin Fast Drying Colour) to save time and then go on to complete it with conventional colour.
Underpainting can be done in monochrome using any colour, or it can be done in full colour if using fast drying colours.
|
| |
|
Back to top
Oiling out
Oiling out is the application of an oil medium to a painting which has sunk (become dull), or lost its oil to the layer underneath. The most common causes for this are an over- absorbent, cheap ground or the use of too much solvent and insufficient or no medium. When the colour is dry, Artists’ Painting Medium should be sparingly rubbed into any sunken areas with a clean cloth.
Wipe off any residue and leave to dry for a day or two. If smaller, dull areas remain, repeat the process until the painting has regained an even sheen. Varnishes should not be used for the purpose of recovering the lustre of a dead painting. For a faster drying oiling out medium, use Thickened Linseed Oil diluted with 50% white spirit (mineral spirits).
See related FAQ for ‘oiling out’
Why is my oil colour crawling when I leave it to dry?
Back to top
Fat over lean
Fat over lean is better understood if considered as ‘flexible over less flexible’. When painting in layers, the proportion of medium used in each layer should be increased. The higher proportion of medium makes subsequent layers more flexible and prevents the painting from cracking. This rule has traditionally been kept by adding more and more oil to the solvent used. However, as Liquin is now more commonly used, it is the Liquin content which is increased. There is no need to use oil as well.
See related FAQs for ‘fat over lean’
Can I intermix different colour media?
How can I stop my paint from flaking?
Do I have to use oils as well as solvents when painting with oil colour?
Back to top