Storing Paints So They Last Between Sessions

Paint is cheaper to keep than to replace, and most waste happens in the gap between sessions. Caps crust shut, acrylic grows a skin, watercolour pans go mouldy in a damp box, and a tube left on a radiator separates or bursts. A few unglamorous habits at the end of the sitting prevent almost all of it.

Tubes: the thread is the whole secret

Wipe the neck of the tube before you cap it. A collar of dried paint in the thread is why the lid will not seat, and air then dries the rest of the tube. Squeeze from the end and roll the tube up so you are not chasing a pocket of paint near the crimp. If a cap has stuck, grip it with a cloth rather than with pliers on a soft metal tube you can split.

Oil tubes, closed cleanly, keep for a long time. Acrylic tubes are less patient. Air in the top of a half-used acrylic tube will skin. Squeeze forward, cap firmly, and do not leave the tube open while you drink tea. Slowing Acrylics That Dry Before You Are Ready is about the hour of painting. Storage is about the night after.

Palettes and stay-wet boxes

Scrape a wooden or glass palette if you will not return tomorrow. A skin of old oil mixed into Monday's colour is not thrift. Acrylic on a stay-wet palette can survive if the sponge is damp and the lid actually closes. If you smell mildew, wash the box and start again. A mouldy palette is not a frugal palette.

Wood, Glass or Plastic: Choosing a Palette affects this chore. Flexible plastic that releases a dried sheet is easy to reset. A thumb-hole palette loaded with last month's greens is a colour problem disguised as storage.

Pans, jars and the cupboard

Watercolour pans are supposed to dry. Let them dry with the lid open, then close the box. Shutting a soaking set invites mould, especially in a cool damp room. If a cake cracks, it is usually still usable. If it blooms with fuzz, it is finished.

Jars of medium and solvent need their lids. Solvent evaporates and fills a cupboard. Keep it small in quantity and closed. Store paint away from heaters, cookers and the dashboard of a car. Heat splits tubes. Freezing is no kinder to water-based paint. A ordinary cupboard, out of the sun, is the correct piece of equipment.

A two-minute end to the sitting

Before you wash brushes, and you should wash them as How to Clean and Care for Your Paint Brushes describes, close the tubes. The order matters because an open tube is forgotten once you are at the sink. Stand back and look at the table. One open lid is the tube you will throw away next month.

Write the date on a jar you decanted, if you decant at all. Unlabelled mixtures are how a medium you do not recognise enters a painting. When in doubt, do not keep a mystery liquid. Fresh paint from a named tube is a better economy than a jar of unknown oil.

Frequently asked questions

Should tubes stand cap down? A clean cap, firmly closed, matters more than the direction. If a tube is very runny, cap-down storage can keep paint at the neck ready to use, and it can also leak if the cap is dirty. Seal first. Then choose a direction.

Can I revive a stiff acrylic tube? If the paint inside is still moist, a drop of water may loosen it. If it has solidified, it is cured plastic. Soaking will not turn it back into paint. Prevention at the cap is the only reliable revival.

How long do oil paints keep? A sound tube kept closed and cool keeps far longer than a typical gap between paintings. The failure is air and a split tube, not a calendar. If the paint smells harshly unlike itself or has separated into a liquid you cannot stir back, retire it.