Two of my most visited posts are Sandy demonstrating how to fold a plastic bag and my Youtube video on how to clean your brushes. With the advent of plastic bag bans you may have other ways to deal with your plein air trash, but we all still need to clean our brushes.
Itâs especially hard to keep oil painting brushes nice when youâre on the road. Thereâs seldom a utility sink available, and itâs not nice to repay your hosts by washing brushes in their kitchen sink. In a pinch, I shower with mine, since theyâre usually no dirtier than I am. Sometimes I wrap them in plastic and hope for the best. And that best, after a week in a hot car, usually isnât very good.
A cardinal rule of brush care is to never let brushes stand on their bristlesâin mineral spirits or water. That includes during painting. Thatâs one reason why a small, swinging solvent holder is a great ideaâit tips over if you leave a brush in it.
Watercolor brushes
In general, watercolor brushes need to be rinsed when youâre done painting, shaped back into their proper form, then allowed to dry flat. They will dry just fine in a brush roll, but not in a sealed plastic container.
Pay particular attention to rinsing them if you paint with saltwater or use alcohol to prevent freezing.
Unless youâve done something very silly, thereâs never any reason to use soap; in fact, itâs not good for fine hair brushes.
Oil and acrylic brushes
For oils (and to a lesser degree, acrylics) brush care is serious business. Itâs possible to clean acrylic paint out with running water alone, but soap wonât hurt hog bristle or synthetic brushes and it will save water.
Synthetic brushes are generally easier to clean than hog bristle brushes. This is the upside of synthetic brushesâ downside; they carry less pigment, so thereâs less pigment to clean out.
Soap is not detergent.
Soap starts with a natural fat to which an alkali (like lye) is added. Detergents are synthetic cleaning compounds. They often have additional surfactants added to increase their oil-stripping qualities. Both allow oil to be lifted out with water, but soaps are gentler. Thatâs also why we donât use detergent to wash our hair; itâs too good at removing oils.
Donât leave brushes standing around dirty
The secret of brush-cleaning is to get to them fast. Get as many solids as you can out with mineral spirits; that will prevent clogging your sink. Thoroughly coat them with soap, inside and out, and wash them with a rag, not your bare hand. (Even the least-toxic of pigments shouldnât be ground into your skin.) The brush is clean when the water runs clear, and not before.
If you left your brushes standing and theyâve started to harden up, detergent wonât work any better than soap at softening the mess. I sometimes pre-treat them with coconut oil when I canât get the paint out.
Donât expect heavily-used brushes to last forever. Theyâre made of hair and they wear out. In fact, most of my filberts started life as flats. But by cleaning your brushes regularly, youâll ensure that they will last as long as is possible.
A plug for my daughterâs soap
My daughter Mary makes my brush soap. I offer it (in small batches) to my readers. Maryâs been offline as she prepped and sold her house, but sheâs got her soap lab up and running again. You can order her soap here. âYour brush soap is seriously great. Better than Murphyâs or the pink stuff from Jerryâs. I can always âget a little more outâ with yours,â said my student, Mark Gale.
Iâm in Britain on another lovely, long, blister-inducing hike. Iâve turned my phone off and while Iâm gone, Laura will be running the office. Just email me as usual if you have questions or problems registering for a class or workshop. (Who am I kidding? She fixes all that stuff anyway.)
Reserve your spot now for a workshop in 2025:
- Canyon Color for the Painter, Sedona, AZ, March 10-14, 2025
- Advanced Plein Air Painting, Rockport, ME, July 7-11, 2025.
- Sea and Sky at Acadia National Park, August 3-8, 2025.
- Find Your Authentic Voice in Plein Air, Berkshires, MA, August 11-15, 2025.
- Immersive In-Person Fall Workshop, Rockport, ME, October 6-10, 2025.
Your soap is brilliant, it really works!
I have soaked oil brushes in walnut oil to soften the paint after inadvertently leaving one on the easel for a time.
At a spot where I volunteer, cleaning acrylic brushes is a constant problem. (We could go through dozens and dozens if not careful.) A day or two in Murphy’s Oil Soap can work wonders to rehab dry brushes. They won’t be new, but many can be largely salvaged.
I’ve been a Murphy’s fan for many years, even considering I happen to be allergic to it as it’s formulated now if I breathe it enough to smell it..
BUT: and a huge but: I use synthetic brushes because I like the way they handle paint in smaller paintings. Get most oil paint out out by using your brush cleaner with Gamsol,, wipe, then put them in a jar with 1/2-3/4″ Murphys in the bottom. Mush it a couple of times to get the Murphy’s up as far as possible, and leave standing there overnight! Rinse out the next day, and you’re golden.
Does NOT work with bristle. Softens it too much.. And obviously, with synthetic brushes, leaving them in the Gamsol is a huge no-no. Oh – and if you use acrylic, it will make Murphy’s solidify. Got me.