Acrylic pouring for beginners: pouring medium, consistency, cells and safety

TUREFF• •0

Acrylic pouring, or fluid art, is paint thinned until it flows, then poured onto a surface and tilted to create marbled patterns. It is fun, no drawing skills are needed and every piece is different. It also uses a lot of paint and makes a lot of mess, so a little preparation goes a long way.

What you need

Acrylic paints (student grade is common for pouring because of the volume used)
A pouring medium
Cups, stirring sticks and a measuring cup
A primed canvas or panel
Something to raise the canvas off the table, such as cups or push pins in the back corners
A large tray or plastic sheet to catch drips
Gloves and old clothes

Why use a pouring medium?

You could thin paint with water alone, but large amounts of water weaken the acrylic binder, and the result can crack, craze or dry dull. A pouring medium thins the paint while keeping enough binder for a strong, even film. Some people make their own mixes with PVA glue, but artist pouring mediums are made to stay flexible and clear.

Getting the consistency right

This is the most important skill in pouring.

The usual starting point is to mix paint with pouring medium in a ratio given by the medium's maker, then add a little water if needed.
A common target is paint that flows from a stirring stick in a smooth stream and settles back flat on the surface in a few seconds.
Too thick: the paint will not spread across the canvas and leaves lumps.
Too thin: colours run into each other and become muddy, and the paint can craze as it dries.
Mix slowly to avoid trapping air bubbles, and let mixed cups rest a few minutes.

Basic pour techniques

Flip cup: layer colours into one cup, place the canvas on top, flip, lift and tilt.
Dirty pour: layer colours into one cup, then pour straight onto the canvas and tilt.
Puddle pour: pour each colour one at a time in puddles, one inside another.
Swipe: pour colours, then drag a thin layer of white across the top with a paper towel or card to reveal patterns.

Tilt slowly to cover the edges, then leave it flat to dry.

How cells form

Cells are the round, lacy shapes that appear when colours push up through each other. They form because of differences in density between colours, and many pourers add a few drops of silicone oil or similar to encourage them.

Silicone can leave an oily residue on the surface. Wipe it off gently once the painting is fully dry, before varnishing.
Silicone may cause problems with adhesion of later layers or varnish, so clean thoroughly and test first.
Cells also form without additives, just less dramatically.

Using heat

Some pourers pass a kitchen torch or heat gun briefly over the surface to pop bubbles and bring cells up.

Keep the flame moving and do not scorch or boil the paint.
Work in a ventilated space, away from anything flammable.
If you are unsure, skip the torch; it is optional.

Drying

Pours are thick and can take a day or longer to be dry to the touch, and longer to dry through. Keep the canvas flat and level, away from dust and pets. Cracks in a pour are often caused by drying too fast or paint that was too thin.

Safety

Wear gloves to keep paint off your skin, and work in a ventilated room.
Read labels, especially on any additives.
Do not sand dried acrylic without a dust mask.
Keep pouring materials away from food and from children and pets.

Disposing of paint and paint water

Acrylic paint is plastic once dry, and pouring produces a lot of waste paint. Avoid pouring large amounts of paint or paint water down the sink or into drains.

Let paint water stand so the pigment settles, pour off the clearer water and let the sludge dry.
Mix leftover paint with cat litter, sawdust or paper so it dries out, then dispose of the solid in household rubbish.
Scrape leftover paint from cups and let it dry into "skins" before throwing them away.
Check your local authority's guidance on paint disposal, which varies.

Share a photo of your first pour, or the consistency problem that is driving you mad, in the comments.