The lyf so short, the craft so long to lerne” - Chaucer.

Lazy, angst-ridden tutors stopped teaching craft and technique long before I went to college in the late ’70s. Sloppy artists have always ignored it. The consequence is simple — whoever made the fabulous Babylonian Ram in a Thicket knew enough to make a work that has lasted thousands of years; when Picasso and Pollock used car enamels on unprepared cotton they gave the restorers an almost immediate headache. A migraine, in fact.

First comes the surface that is painted, called the support. In oil painting this is usually canvas, in watercolours, paper. Modern acrylic primers may help to stabilise even poor canvas, but natural fibres such as linen, silk and hemp (‘canvas’ is synonymous with ‘cannabis’) can have a life of hundreds of years. Cotton quality is variable, but it will usually last only for decades. Jute, or sackcloth, has a very short life — though Gauguin managed to use it for his masterpiece Who am I? Where am I? Where am I going to?

Wooden panels require very careful attention, but can last as well as good quality linen. But you cannot use just any old plywood. Both copper and pure aluminium have proved good supports, too. I use alkyd oils on aluminium foil for greetings cards, but it is probably not reliable as a long-term support. It should certainly be backed with acid-free card to avoid wrinkling.

Canvas should not be bleached, any residual bleach will interact with the paint layer (oil paints are acidic). My favourite support is heavy-weave, raw, natural linen. For twenty years, I have bought this from Griegs, in Kirkaldy , Scotland (phone: 01592 651901). It is not available through artists’ suppliers, whose cloth is too delicate and way too expensive for me. Griegs only supply in 50 metre rolls, however. The wonderful painter Bill Gear put me in touch with them. This linen provides an excellent, chunky surface. It would not be suitable for smooth-surface portraiture.

Canvas is stretched onto a wooden frame, known as a stretcher. Properly made, these allow wedges to be pushed into the corners, to further stretch the painting if it becomes loose. For reasons of expense, many painters make simple stretchers that are not actually stretchable. Their paintings will likely sag over the years. Mounting a painted canvas onto a new stretcher is a professional job; much better to use a good stretcher at the outset. Bird and Davis make stretchers for artists’ suppliers. In the decades since I first used one of their stretchers, not one has ever warped. Cheap stretchers are made from improperly seasoned wood, and will twist.

I staple the linen onto the stretcher before priming. I staple only to the back of the stretcher (not the edge), doing one long side first, from the centre, and then the opposed side (also from the centre). The two shorter sides are then stapled, again beginning at the centre. The corners are folded and stapled last — they have to be folded so that the canvas can be stretched. Linen needs only hand-tightness (no need for canvas pliers), as it will shrink slighty as the primer dries. I would not buy ready-primed canvas.

Many painters think that they can get away with vinyl housepaint as a primer. It is a false economy. Vinyl housepaint is not compatible with either oil or acrylic artists’ paints. Incompatible paints risk cracking and bleed-through. If you have to economise, use a fast-drying acrylic wood primer, and buy it in 5 litre buckets from a decorators’ merchant. I would not do this — foolish to use the best linen and the best paint with a layer of mediocre paint binding the two together. I use the very best: two coats of Lascaux gesso over Lascaux size, supplied by Fitzpatrick. Mix a little water into the size (about one part to ten), and once applied leave it to dry thoroughly (a few hours, at least; it depends on humidity), then the first of two coats of gesso, leaving several hours between. This needs at least 24 hours before an oil or alkyd oil paint is put on it. Primer is a necessity to isolate the paint from the canvas, otherwise it will soak into the cloth, and the acid in the paint will eat it away.

Oil paints are beautiful, but they suffer from certain limitations. Most obvious is that over time the linseed and poppy oils used as a medium will brown. Devotees will tell you that over the years, oils gain ‘inner light’ as the layers become more transparent. This is because linseed oil does not ‘dry’. It gives off excess spirit within a few days and feels dry, but it actually oxidises over decades, and can take up to 150 years to transform into its final state. Wrongly applied it will also crack over this period. The old maxim is ‘fat over lean’, which means that the first layers should have less oil in them than each subsequent layer, so in the first layer you thin the paint with turpentine (so that it has less oil — or fat — in it), then you work to unthinned paint (as it comes from the tube — paste or impasto), and then thin more and more with oil until you have transparent glaze layers. Renaissance painters knew this rule — look at a Titian or a Caravaggio, and see how well they have lasted. However, the otherwise brilliant Leonardo got cocky, and the crazed surface of the Mona Lisa is the consequence. This is probably because he kept working on it for so many years, and ended up putting leaner paint over fatter (it may also be because of an incompatibility between media in the layers).

Apart from its gradual browning, oil paint is also slow to dry — usually taking about three days for an unthinned colour (though Alizarin Crimson can take a couple of weeks). This means that it attracts both dust and impatience. In the twentieth century this impatience led to most painters using an alla prima or wet-into-wet technique. This has the virtue of side-stepping the hazards of lean-over-fat painting, but the disadvantage of throwing away the gradual and subtle layering used by previous generations of artists.

Acrylic paint is a marvellous innovation, but because it is water-thinned it does not retain the mark of the brush: it shrinks as it dries. For a long time the only high quality acrylic artists’ paint was Aquatech. It shrank far less than other paints and retained high-colour, where others seemed washy or muddy in comparison with oils. Nowadays, most artists’ quality acrylics are useable. Acrylics should not brown with time. They do have the disadvantage of being toxic. I once watched in horror while a painter rolled himself a multi-coloured cigarette having failed to wash his hands. You don’t want to eat this stuff; you most definitely don’t want to smoke it. Linseed oil is sold as a food supplement, but the pigments added to it — especially heavy metals such as cadmium and cobalt — are often toxic.

During the development of plastics, a combination of alcohols and acids rendered the highly permanent paint medium called alkyd. Some formulation of this is now the basis for most decorators’ gloss and eggshell paints (including ICI’s Dulux Satinwood). Alkyd is a general term, so one alkyd medium can differ hugely from another. A few years ago, I tried to make my own paints, and was annoyed that neither of the artists’ quality alkyd media I bought produced the much vaunted buttery quality of good oils. Drippy would have been a better description. So that was four hundred quid up the spout (please let me know if you want to buy a collection of fabulous pigments).

On the subject of home-made paint, even the finest loose pigments will not have been ground to the consistency of those in artists’ quality tubed paint. It is one of the sad facts of life. For once the hand-made is inferior to the machined. Largely because even Superman would not have the elbow grease to rival the factory rollers and the manufacturers’ triple-milling.

Winsor and Newton’s alkyds are an oil-modified resin, made by polymerizing linseed oil. I first used them in the late 1970s. They were too stiff, but had the advantage of being quick-drying and non-browning. When the company dumped the original range to introduce Griffin alkyds, in the mid-1980s, I bought much of the remaining stock from their London stores. Twenty years later, I still have a few tubes left (including Rose Madder Genuine that cost £1 a tube). Griffin was an important breakthrough — a buttery consistency, top quality pigments, fast-drying, high colour. They were also cheaper than the equivalent oils when introduced. The drawback comes with the small tubes — 37ml.

Painters have become used to wet-into-wet painting, which is the one aplication that oils are slightly better for, because of their slow drying time. However, for traditional layering methods, outdoor work and sketching alkyds are superior to oils. I have paintings made over twenty years ago; the most obvious difference comes in the whites when compared to oils painted at the same time: the oils are definitely browner. Whether this is because they were bound in poppy oil rather than linseed, I don’t know, but the alkyds remain fresh.

Originally, Winsor and Newton claimed that alkyds were intermixable with oils, which made no sense to me. Nor does the practice of mixing quick-drying media (siccatives) such as Liquin into oils. Oils should be stable when painted over alkyds, but not the other way round — a dry layer will crack if the layer underneath is still wet. This is still the fat over lean principle.

Many pigments are used in the production of paints. They are graded according to permanency. Traditionally, full permanency is not awarded until a pigment has actually survived for decades in a south-facing, exposed cold-frame. The worst pigments are termed fugitive. The beautiful chrome yellow that came into use in Victorian times slowly turns first green and then black. Van Gogh probably stabilised it accidentally, by thickening his oil paints with wax. Fugitive pigments should be avoided, even when they cannot be matched by anything else. Unless you intend rapid decay to be implicit in the work.

The craftsman painter should be aware of the problems associated with some pigments. For example, Alizarin Crimson should not be thinned as a glaze. Umbers should not be used in underpainting without being thinned, because they are oil rich. The colour charts provided by colourmen are a necessity in choosing and using paint. It is also part of craft to understand the use of more and less opaque pigments. For instance, if using a yellow earth, Yellow Ochre is opaque, and Raw Sienna is transparent. So use Yellow Ochre for impasto layers and Raw Sienna for glazes. The less medium you mix into the tube paint, the stronger the pigment colour will be, so it is good to know the relative transparency of all colours if you use glazing. Cadmium Red Deep is opaque, Alizarin Crimson is naturally transparent; they give quite different effects.

Hog bristle brushes are normally used in oil painting. The two types of available bristle are French and Chinese. Chinese brushes tend to be far cheaper. I like tradional European round copper-ferrule decorators’ hogs — marketed as Decor by Stanley in DIY shops — and Langnickel artists’ brushes from the US , which have longer bristles than other brushes. They give a more calligraphic mark. I have collected perhaps hundreds of brushes over the years, and it is well worth becoming familiar with the different uses of the available array — from fan brushes to riggers, filberts, flats and rounds. I also use painting knives of many makes and Forsline and Starr paintshapers (whenever I find them in a sale, as they are prohibitively expensive). I belong to the school that advocates the largest possible brush or knife for the job. It is amazing how delicate the mark of a 1½ inch watercolour wash brush can be. But if you want that marvellous Andrew Wyeth tempora look, you will have to buy some teeny brushes (and make some tempora paint).

Oil paintings should not be hung in a room where there is an open fire, nor where the atmosphere contains either smoke or cooking oils. No type of picture can be safely hung in a humid atmosphere, such as a bathroom.

Turning to watercolours, the usual support is paper, although silk can also be used (it must be raw, untreated silk). Paper should be acid-free, so that the acids do not eat the paper. The same is true for any mounting or backing board used with a watercolour, and when framed the paper should not touch the glass. Acid-free, wood-pulp papers are fine, but rag papers are better. Some painters prefer hand-made papers, and pay for the privilege. I don’t mind who or what made the paper (Salvador Dali doubtless employed wasps). The surface of a good paper has a biscuit dryness, achieved by sizing the paper (usually with gelatin: strict vegetarians beware) to make sure that the paint adheres but does not sink in. Blotting paper would not be suitable for watercolours, but nor would polythene. I have used a lot of hand-made papers, but still prefer Arches’ Aquarelle to any other paper. It is perfect for rapid wet-technique painting. Painters who want to work the surface more — or use razor blades and the like — are better off with a heavy, handmade paper with a more obvious texture.

I use both the torchon (rough) and the fin (cold-pressed) Arches’ papers. Usually the former. On special occasions I use a sheet from my small stock of Whatman paper, watermarked either 1955 or 1963.

There are many fine artists’ quality watercolours available. I use Winsor and Newton or Rowney as tube colours. I do not use pans. As with alkyds, I only use permanent colours, and check everything carefully against the colourman’s chart.

Sable hair brushes are traditionally used for watercolour painting, in many shapes and sizes. Cheaper brushes are made from squirrel hair. Many painters prefer nylon and mixed bristle brushes. For the most part, I use Daler’s Dalon range. I am annoyed that the D88 1½ inch wash brush is no longer available, and would gratefully receive the donation of the same. It is important not to use a brush for both oil and watercolour. Traces of medium from oils or alkyds can compromise the watercolour paint. Acrylic paints will tend to solidify the bristle near the stock. So keep your watercolour brushes separate.

All artists should be aware of manuals that deal with craft. I have long used Mayer, Hiler and Doerner. There are probably newer and more straightforward works, as the scope of these is far too broad for most contemporary artists (though you may fancy using Damar varnish or Oil of Spike Lavender, or making your own oak veneer boards). New editions are better for new materials, but older ones can give fascinating insights (Hiler wrote in the 1930s about begging old brushes from decorators, because if properly used the bristles would be extremely supple. Not much hope of that these days).

Craft is precious. It is the respect that an artist shows to the viewer. Wedded with good technique and strong inspiration good craft produces exceptional work. Without sound craft, the most skillful technique and the highest inspiration are lost — the paint fades, tarnishes, cracks or simply falls off the surface. Craft is the foundation of all great art.

August 2004