Tips on Oil Painting – Canvas Priming
November 9, 2009 by admin
Filed under Visual Art
Remi Engels, Ph.D. asked:
When you refuse to buy any of the pre-fabricated canvases you can always buy a roll of primed or raw canvas cloth. The first step in the process towards constructing a finished canvas is the stretching of the canvas. Once the stretching is done it is time to prime the canvas cloth if you bought a roll of raw canvas.
The reason it is necessary to prime a raw canvas is that both linen and cotton cloth will eventually rot when saturated with oil paint. To prevent the occurrence of rotting the canvas cloth must be treated with a glue or gelatin solution to so-call “size” the canvas and then coated with an oil-based primer.
Here are the steps to be executed in the priming process:
1) After stretching the raw canvas, evenly brush the weak glue or gelatin solution onto the raw canvas using a wide nylon or bristle brush. Note, do not stretch raw canvas too tight, because the priming will shrink the canvas cloth and therefore tighten it automatically.
2) When the fabric dries, coat it with a mixture of white lead in oil and turpentine, again using a wide brush. The brilliant white surface that results makes it easier to gauge the colors you will be using while you paint.
3) Once the canvas is dry, sand it lightly.
4) Then, apply a second coat of the white lead in oil and turpentine solution, and sand the canvas again.
All these materials and the accompanying instructions can be bought in a serious art supply store or on the Internet.
Many artists also enjoy working on wood panels, which is a proving support for oil painting. The old masters worked on oak, poplar, and mahogany, but today “wood panel” can mean anything from a piece of poplar to plywood to Masonite. The latter is increasingly popular because it is inexpensive, durable, and can be cut into virtually any size.
Wood panels are perfect for rendering intricate, detailed subjects where the weave of the canvas might be too uneven. You can buy prepared boards or you can make your own. You must prime the panel with gesso before you begin painting. Dilute the gesso with water; apply it with a wide housepainter’s brush, let it dry, and then sand it smooth. Repeat the process two or more times. If you like a slighter rougher tooth, add less water and do not sand the board.
You can also oil paint on watercolor paper or vellum. You can size the paper with an acrylic medium first so that the oil paint does not eventually rot the paper. If you want to make your painting last longer (permanence) you need to choose heavy paper of at least 200 lbs.
This is the end of short primer on priming different grounds for the purpose of oil painting. There is much more to learn but this will give you enough information to go to a reputable art supply store and be able to converse intelligently on the subject of priming and priming methods. This will certainly start the conversation and you will learn right there about the latest techniques and inventions regarding priming and while you’re at it also about stretching canvases.
When you refuse to buy any of the pre-fabricated canvases you can always buy a roll of primed or raw canvas cloth. The first step in the process towards constructing a finished canvas is the stretching of the canvas. Once the stretching is done it is time to prime the canvas cloth if you bought a roll of raw canvas.
The reason it is necessary to prime a raw canvas is that both linen and cotton cloth will eventually rot when saturated with oil paint. To prevent the occurrence of rotting the canvas cloth must be treated with a glue or gelatin solution to so-call “size” the canvas and then coated with an oil-based primer.
Here are the steps to be executed in the priming process:
1) After stretching the raw canvas, evenly brush the weak glue or gelatin solution onto the raw canvas using a wide nylon or bristle brush. Note, do not stretch raw canvas too tight, because the priming will shrink the canvas cloth and therefore tighten it automatically.
2) When the fabric dries, coat it with a mixture of white lead in oil and turpentine, again using a wide brush. The brilliant white surface that results makes it easier to gauge the colors you will be using while you paint.
3) Once the canvas is dry, sand it lightly.
4) Then, apply a second coat of the white lead in oil and turpentine solution, and sand the canvas again.
All these materials and the accompanying instructions can be bought in a serious art supply store or on the Internet.
Many artists also enjoy working on wood panels, which is a proving support for oil painting. The old masters worked on oak, poplar, and mahogany, but today “wood panel” can mean anything from a piece of poplar to plywood to Masonite. The latter is increasingly popular because it is inexpensive, durable, and can be cut into virtually any size.
Wood panels are perfect for rendering intricate, detailed subjects where the weave of the canvas might be too uneven. You can buy prepared boards or you can make your own. You must prime the panel with gesso before you begin painting. Dilute the gesso with water; apply it with a wide housepainter’s brush, let it dry, and then sand it smooth. Repeat the process two or more times. If you like a slighter rougher tooth, add less water and do not sand the board.
You can also oil paint on watercolor paper or vellum. You can size the paper with an acrylic medium first so that the oil paint does not eventually rot the paper. If you want to make your painting last longer (permanence) you need to choose heavy paper of at least 200 lbs.
This is the end of short primer on priming different grounds for the purpose of oil painting. There is much more to learn but this will give you enough information to go to a reputable art supply store and be able to converse intelligently on the subject of priming and priming methods. This will certainly start the conversation and you will learn right there about the latest techniques and inventions regarding priming and while you’re at it also about stretching canvases.
Tips on Oil Painting – Solvents Mediums and Varnishes
October 21, 2009 by admin
Filed under Visual Art
Remi Engels, Ph.D. asked:
If you paint with oils you will need a solvent to clean your brushes and thin your paints. Of course, if you paint with water soluble oils then your solvent will be water.
Turpentine is a standard solvent used to thin ordinary oil paints. You can purchase turpentine in any art supply store or hardware store. In some cases, the kind of turpentine you buy in a hardware store may be fresher because of the shorter turnaround time.
Some artists work with mineral spirits. These are also available in hardware stores. To save money, buy the largest available quantity and use a smaller container when you do your actual painting.
Tube oil paint (i.e., oil paint directly from the tube) can be difficult to manipulate. Some colors are stiffer than others and may be hard to evenly distribute over your canvas. To solve this problem, artists often need to mix their tube paints with a so-called painting medium.
A painting medium is a liquid solution that makes the oil paint smoother and easier to manipulate. Adding any one of a number of different painting mediums changes the consistency of the paint. Some mediums are meant to make the paint thinner for glazing and others are meant to make the paint thicker for impasto painting. There are also mediums to shorten or lengthen the drying.
The most basic medium is regular turpentine. Adding a little turpentine thins oils paint. Another frequently used medium is linseed oil, which makes the paint more fluid but, over time, it also tends to yellow the paint. The most commonly used medium is a combination of turpentine and linseed oil, sometimes with the addition of a little damar varnish.
Begin by experimenting with a half-and-half mixture of turpentine and linseed oil. Because linseed oil slows down the drying process, you may want to increase the proportion of turpentine. A good mixture is three parts of turpentine to one part of linseed oil.
Once you find the medium you like, mix a batch and store it in a tightly sealed jar. As you paint, dip your brush into the medium, then add a little paint, then mix them together on your palette (mixing surface).
Preliminary compositions can be drawn on your canvas with a so-called thin turp wash, i.e., a little bit of paint with a lot of turpentine. A turp wash evaporates very quickly, so you can quickly paint over them.
In general, the more turpentine you use the matter the finish will be and the more linseed oil you use the glossier it will be. If you like robust, permanently visible brushstrokes, you may want to use less medium. Dry brush is one technique where you do not add any medium at all.
Special painting mediums are also available that change the oil paint in different ways. The most common are those that shorten or lengthen the drying time of the oil paint. Check your art supply store or the Internet to see the available types of mediums. All medium bottles will show instructions on how best to use the particular medium.
Oil paintings must be varnished to protect them from undesirable elements such as dirt and toxins. Varnish is a clear solution made from a resin and turpentine or some other solvent.
In art-supply stores you will see two major types, retouching varnish and picture varnish. Depending on the paint layer thickness, it can take six months or more for an oil painting to dry. In the meantime, the surface of the painting needs to be protected with a coat of retouching varnish. After the varnish is applied, the turpentine evaporates, and leaving a thin protective coat. You can apply retouching varnish as soon as the paint feels dry to the touch.
Picture varnish contains more resin than retouching varnish. It should be applied about six months after you complete a painting. If you paint with impasto-like brushstrokes, you may have to wait as long as a year before applying the final coat.
Both types of varnish are applied in the same manner. Using a broad, flat nylon brush, apply the varnish evenly using horizontal strokes. You can also use retouching varnish to brighten dry dull patches in your painting.
If you paint with oils you will need a solvent to clean your brushes and thin your paints. Of course, if you paint with water soluble oils then your solvent will be water.
Turpentine is a standard solvent used to thin ordinary oil paints. You can purchase turpentine in any art supply store or hardware store. In some cases, the kind of turpentine you buy in a hardware store may be fresher because of the shorter turnaround time.
Some artists work with mineral spirits. These are also available in hardware stores. To save money, buy the largest available quantity and use a smaller container when you do your actual painting.
Tube oil paint (i.e., oil paint directly from the tube) can be difficult to manipulate. Some colors are stiffer than others and may be hard to evenly distribute over your canvas. To solve this problem, artists often need to mix their tube paints with a so-called painting medium.
A painting medium is a liquid solution that makes the oil paint smoother and easier to manipulate. Adding any one of a number of different painting mediums changes the consistency of the paint. Some mediums are meant to make the paint thinner for glazing and others are meant to make the paint thicker for impasto painting. There are also mediums to shorten or lengthen the drying.
The most basic medium is regular turpentine. Adding a little turpentine thins oils paint. Another frequently used medium is linseed oil, which makes the paint more fluid but, over time, it also tends to yellow the paint. The most commonly used medium is a combination of turpentine and linseed oil, sometimes with the addition of a little damar varnish.
Begin by experimenting with a half-and-half mixture of turpentine and linseed oil. Because linseed oil slows down the drying process, you may want to increase the proportion of turpentine. A good mixture is three parts of turpentine to one part of linseed oil.
Once you find the medium you like, mix a batch and store it in a tightly sealed jar. As you paint, dip your brush into the medium, then add a little paint, then mix them together on your palette (mixing surface).
Preliminary compositions can be drawn on your canvas with a so-called thin turp wash, i.e., a little bit of paint with a lot of turpentine. A turp wash evaporates very quickly, so you can quickly paint over them.
In general, the more turpentine you use the matter the finish will be and the more linseed oil you use the glossier it will be. If you like robust, permanently visible brushstrokes, you may want to use less medium. Dry brush is one technique where you do not add any medium at all.
Special painting mediums are also available that change the oil paint in different ways. The most common are those that shorten or lengthen the drying time of the oil paint. Check your art supply store or the Internet to see the available types of mediums. All medium bottles will show instructions on how best to use the particular medium.
Oil paintings must be varnished to protect them from undesirable elements such as dirt and toxins. Varnish is a clear solution made from a resin and turpentine or some other solvent.
In art-supply stores you will see two major types, retouching varnish and picture varnish. Depending on the paint layer thickness, it can take six months or more for an oil painting to dry. In the meantime, the surface of the painting needs to be protected with a coat of retouching varnish. After the varnish is applied, the turpentine evaporates, and leaving a thin protective coat. You can apply retouching varnish as soon as the paint feels dry to the touch.
Picture varnish contains more resin than retouching varnish. It should be applied about six months after you complete a painting. If you paint with impasto-like brushstrokes, you may have to wait as long as a year before applying the final coat.
Both types of varnish are applied in the same manner. Using a broad, flat nylon brush, apply the varnish evenly using horizontal strokes. You can also use retouching varnish to brighten dry dull patches in your painting.
