The other ways I control the drying time of my acrylic paints is by using a retarder in my paint mixes and by using a moist airtight container to store my squeezed out paints in.
A retarder is an acrylic medium (sometimes called a Slow Drying Medium) that when added to the acrylic paints slows down their drying time and keeps them “open” or “workable” for a longer period of time. They basically slow down the evaporation process of the water within the paints.
I use the retarder in two ways. The first way is to add it to my paint mixes via my “mixing white”. I make my mixing white using Titanium White but I add a retarder to it in a ratio of 2:1 and mix it thoroughly. I prefer a thick gel style of retarder similar to the consistency of the paint as opposed to a liquid one which can thin down the paint. By adding the retarder to this mixing white I am making it dry more slowly and therefore it is “open” or workable for longer.
My “mixing white” is added to my colours to make tints. These tints make up the majority of my colour mixes. Using this white with the retarder in it, I have effectively made my colour mixes slower drying or “open” as well. The only colour mixes that don’t contain the retarder are my darks or “shades” and I usually like these to dry fast anyway so as they can be painted over with the slow drying tint.
The second way I use the retarder is by adding it to my fine mist spray bottle. I do not want the spray to be a jet or produce large droplets of water, as this makes the paint watery and runny which makes it very difficult to pick it up and to spread thickly on the canvas. It is paramount that my
paints have a thick consistency in order for me to achieve an “oil-like” look to my work.
My spray bottle contains rain water but with the addition of retarder in a ratio of 10:1. Once the water is added to the retarder in the spray bottle I shake it to mix the two ingredients thoroughly. I use this to keep my mixes usable and my paints moist and “open”. Without the use of a spray bottle, I would find that my paint and mixes would dry too rapidly for any worthwhile application. I believe this procedure is an essential part of painting using acrylics.
The next way I make painting with acrylic paints less frustrating and more practical is the way I store them for long periods of time and not have them dry out. I do this by placing my paints into a storage device called a “Palette Garage” which is designed to keep paints moist for weeks. If I break for a “cuppa” or overnight (or for weeks), I put my squeezed out paints, which are on the “L” shaped insert, into a humid environment. When I am ready to paint again, my paints are there waiting to be used. This not only saves me time, but also saves paint.
No more dry blobs of paint as soon as I turn my back. I believe this is the reason painting in acrylics is so frustrating for some artists. Unless you are working with large amounts of paints that will stay wet by sheer volume or you are working at a very fast pace, the paint will skin over or dry completely, making them useless.
If you are a slow painter like me, having a way to keep your paints moist while you take a break is very advantageous and this single bit of equipment has made painting in acrylics, like painting with oils.
An alternative to using the “Palette Garage” is to use a “Sta-wet” palette or placing your palette of mixes and squeezed out paints in the fridge or freezer overnight (they don’t even have to be covered).