Oil Painting Care
Avoid extreme temperature, including hot cars. Don't hang near fireplaces, showers, or kitchens. Temperature changes cause the canvas to expand and contract, making the paint crack and maybe fall off. High humidity leads to mold growth.
Handle it by the sides and the back bars. These are the strongest points.
Don't lean the canvas on anything that bends it. Might cause tears, and leads to cracking years later.
Don't leave the paint surface touching anything for more than a few minutes. Until the paint is fully dried (a few years) it can be pressed out of shape. Some plastics will melt to the surface and be impossible to fix.
Dust with a lint free cloth, like microfiber or a wypall as needed. People say feather dusters are bad for this because they can lose small pieces that will stick to the paint.
Don't spray with any cleaning products. EVER.
If something is stuck to it, try some water and very light rubbing with a towel. Or call me.
It is okay to gently touch the surface, it's pretty tough. Just wash your hands first, skin oils are slightly corrosive, and who knows what else is on your hands.
Avoid direct sun for more than a few minutes
Sunlight causes colors to change and the canvas to degrade. I made a strip of canvas with different colors on it and left it in my car window for a year, the colors were mostly fine, but the canvas cracked and disintegrated.
Indirect sunlight is probably good for oil paintings, it keeps them from darkening too much. If the painting darkens over the years, especially from being stored in the dark, hanging it in the sun for a few hours will brighten it back up, without causing too much damage to the canvas.
The framer should seal the back side with paper to keep out dust and bugs (spiders love paintings!). Paper lets the painting breathe, and dry out, and discourages mold.
Oil paintings take years to dry, and the chemistry is going on forever, the colors will react with each other and change over time. Modern pigments are generally very stable, but who knows what the manufacturer actually put in the tube, and what will happen fifty years from now. Some layers will dry and contract at different speeds than others, so some parts might separate(crack). Cracks aren't necessarily a problem, unless the paint actually starts to fall off the canvas, which is unlikely. They usually just add more character.
If a painting has been varnished, there is a protective layer that can be cleaned (or removed) if needed without hurting the paint. If something extreme happens, ie. a guest splashed wine on it, or oil from frying in the kitchen settles on it, kids with greasy hands, etc... the varnish can be removed and replaced fairly easily.
