Many novice painters ask themselves the question: do I need to cover my work with varnish if it is written with oil paints? Many artists have used this method. For example, Leonardo da Vinci, in his «Treatise on Painting», called varnish eternal, speaking of a proven means to preserve the integrity of the picture.
If you are against this method, there are certainly good reasons. Some believe that the work is already beautiful, and additional highlights will only ruin it. Others, on the contrary, add clear varnish directly to linen paints and therefore an additional layer on top is not required.
If you still decide to use a coating, then immediately questions arise: «What are the advantages of this method?», «Which varnish to choose so as not to spoil the oil painting?», «How to apply varnish on the finished work?»
When should a painting be varnished? Arguments «FOR» oil painting under a varnish film
Applying varnish to an oil painting is worth it if you want to get your work out of the environment. However, this is not the only reason for varnishing a painting. Let’s list them:
- Varnish protects an oil painting from moisture, air, sunlight, dust and other contaminants that may come from outside. External environmental factors, including grease and soot, can destroy the paint layer. With prolonged exposure, they can cause significant damage to unprotected painting and completely spoil the work. A lacquered painting is easier to clean from dust and dirt by wiping it with a damp soft sponge.
- Glossy varnishes are able to add shine and glow to a picture painted with oil paints. At the same time, the colors become juicy and bright. This method is especially suitable if the oil paints turned out to be muted and dull. However, varnishes are matte. They do not have gloss properties. Be careful when choosing a varnish.
- The topcoat is able to even out layers of paint. Therefore, if you want to make the surface more even, without relief, use varnish. In addition, this method will help hide slight flaws in the picture. For example, when applying layers of oil paint, you have an unpainted piece. In this case, the varnish will hide the unevenness, and the surface of the picture will look uniform.
- Varnish is able to protect your oil painting from minor mechanical damage, such as scratches. Although it is unlikely to save from cuts and dents.
- Lacquer also «preserves» paintings, extending their lifespan. That is why so many old works of art have survived to this day. Although the restorers also need to pay tribute. Therefore, if you want to keep the picture for decades, it is better to cover the dried layers of oil paint with varnish.
The listed advantages of this method of processing oil painting indicate that the lacquer film is an indispensable element of the picture. Therefore, the artist must be able to understand the varnishes and application techniques.
Varieties of varnishes: choose the coating material for oil paintings
In ancient times, when varnishes were not yet sold in stores, artists made them on their own. But the development of a coating in artisanal methods did not save the picture from clouding and tarnishing. Of course, experienced restorers can cope with such changes to the oil canvas. However, along with the varnish, the top layers of paint are also removed. Today, you can choose for the picture the varnish that will not spoil the image over time.
Top coats are suitable for oil paints. These include:
- Dammarny. This lacquer is a budget option. He is the most popular in painting. Its advantages are that it protects the painting from ultraviolet radiation and can also be used as an additive to oil paint. Cons – dammar varnish has a yellowish tint, so it is best to apply it on a canvas painted in warm colors.
- Acrylic-styrene. This is a transparent quick-drying varnish, which, like Dammar varnish, protects the painting from the rays of the sun, but does not turn yellow over time. It has excellent waterproof properties. Acrylic-styrene is applied in 1-2 layers. As a result, you get a picture with a beautiful glossy sheen. This varnish is a great option for oil paintings painted in cool colors.
- Acrylic pistachio. It is suitable for a colder palette. It has an elastic structure and is easy to apply. It is transparent and does not acquire a yellowish tint over time. At the same time, acrylic-pistachio dries longer than the options listed above and costs more than a dammar coating.
- Fir. This varnish, like dammar varnish, is made from tree resin, but is less common. It is equally great if you want to add varnish to paints or limit yourself to a top coat. Fir varnish, although made from natural ingredients, still has a yellowish light.
- Retouch. Based on the name of the varnish, it is immediately clear that it is not for the final coating of the picture, but for intermediate stages. Retouching varnish has the opposite properties of a topcoat: it dissolves unnecessary oil paint and, thereby, enhances the adhesion between the dried and fresh layer.
- Aerosol varnishes. These options dry quickly, are easy to apply and adhere well to the painting. However, it is worth using varnish spraying in a well-ventilated area. Also, aerosol varnishes should be bought in specialized art stores, and not in hair cosmetics departments.
It must also be remembered that varnishes are glossy, matte and satin. Based on what effect you want to achieve – shiny, velvet or satin – the type of varnish you need to choose.
When to Lacquer an Oil Painting?
The artist, working on a painting, can varnish it in several layers at different stages of applying oil paint. For example, to add brightness, you can mix paints with dammar varnish, process intermediate steps with retouch, and finish with acrylic-styrene. It dries quickly and will not turn yellow over time. However, before using varnish, you need to consider a few nuances of its application.
It is possible to process a picture with varnish only after the oil paint has completely dried. How long does it take to dry? This process is influenced by factors such as:
- number of layers;
- use of paint-drying agents;
- room humidity;
- exposure to direct sunlight;
- air supply to the room.
The more layers, the longer the painting dries. In this case, you need to wait for each layer to dry completely. A tee, medium, or desiccant can cut paint drying time in half. Make sure that the painting does not dry in a very damp room. So you can also avoid the formation of cracks. In order for the oil painting to dry faster, leave it in a well-lit and ventilated room.
Do not rush to process the picture with varnish. It is better to wait 4-6 months before proceeding with the final varnishing.
Oil Painting Varnish Tips: Step by Step Instructions
When the painting is completely dry, you can start applying varnish. To do this, you will need a wide and soft flute brush. Make sure that the fibers on it are firmly attached to the base so that you do not have to remove them from the picture later. You will also need a nail polish jar or oiler and wipes to remove excess nail polish.
Then follow the instructions:
- Pour a small amount of varnish into the center of the painting, or first into an oil dish and then onto the canvas.
- From the center, moving smoothly, evenly distribute the varnish over the picture, avoiding smudges.
- If you have not applied enough varnish, add more, and remove the excess with a special napkin.
- Spread all the varnish over the painting evenly.
- You can also varnish the image along the edges of the painting, if it is on a stretcher at the time of processing.
- If it is important to get a beautiful glossy shine, varnish the picture in several layers.
The processed picture is set to dry vertically so that dust particles do not settle on the still «wet» surface. A good and fresh varnish dries on the picture in about a day. Therefore, when buying it, look at the expiration date. Expired may never freeze.
This instruction concerns the traditional application of varnish with a brush. In the case of aerosol varnishing, the process will be faster and easier. However, keep in mind that the consumption of varnish in cans will be higher, but the possibility of smudges, brush marks or lint on the picture is reduced to almost zero.
By following the above guidelines, your oil painting will acquire a vibrancy that will last for many years to come.