For years now I’ve been ‘recycling’ solvent by letting what I’ve used to clean brushes sit for a while until the pigment settles, then pour off and reuse the clean part at the top. Every few years I’d toss the sludge at the bottom. But it turns out that you can make paint out of it. The colour you get is a muddy mix of every hue you’ve used since saving it, but that doesn’t mean it isn’t useful. Or even beautiful.

I don’t recall exactly where I heard of this, but as soon as I did I knew I had to try it. Some tutorials I’ve seen suggest storing the paint in a jar, but then you have to put cling wrap on the surface to prevent it forming a skin, so I much preferred the option of scooping it onto an empty paint tube.

Once I’d hunted down those, I scooped out the sludge from my settling jar, spread it over my mulling slab and picked out lumps and bits of paint bristle. It was much too sloppy a mix, as it would end up quite liquid once I’d added linseed oil. I contemplated leaving it there for a few days for the solvent to evaporate, but since I was doing this indoors (with an exhaust fan going), I didn’t want to leave fumey, wet paint exposed for long. So I scooped it up into a coffee filter, folded the edges in and left it overnight. The next day I was chuffed to find it had worked. The sludge was now a typical oil paint consistency.

I spread it on the slab again and added a bit too much linseed oil because it came out of the bottle too fast. Next time I’ll use a spoon or dropper. I mulled it for a while, then scooped that into an empty paint tube and folded over the end. There was exactly enough to fill the tube.

The colour is a paleish browny green. I’m planning to use it for sketching in at the start of paintings. It’s not so muddy a colour that I can’t imagine it being useful apart from it being a bit runny.

It also gave me another idea – to premix shades I mix up a lot, like the alizarin-viridian combination that makes a great black, which I use in almost every painting. I have some smaller tubes I can use for that. It’ll save time when setting up to paint plein air.