Brush Spa: Caring For Your Brushes

There’s a lot of confusion in online circles on how to care for watercolor brushes, perhaps because their care is so different from oil and acrylic brushes.  With watercolor, it’s all about damage prevention.  Be nice to your brushes and they will last for decades!

How To Be Nice To Your Brushes

The main goal is to maintain the point (of your round brushes) or edge (of your flats).

1. Never, never leave your brush sitting in your rinse cup as this will squash the brush tip against the bottom of the cup and ruin it.  It can also damage the finish on the brush handle and dissolve the glue that holds the brush together.  Even while your painting is in progress, rinse with a quick swish in your water jar, then set your brush on a rag or brush rest when not in use.  Watercolor will rinse out just as well 20 years from now as it will today, so you don’t need to stress about it drying in the brush.
2. When you dry your round brushes after rinsing, wipe them gently on a rag or paper towel at an angle that matches the taper of the brush while slightly twisting to maintain the pointed shape. Never dry a round brush by wringing it out or squeezing the water out with your fingers as this will flatten it. 
3. When you pick up paint from a dry pan, lightly brush across the surface of the pan as though you’re painting it with water. Don’t use the point of the brush to drill into the pan as this will damage the point.  Artist Jane Blundell pours pans at an angle to help facilitate proper paint pick-up, which is an excellent way to train yourself to be nice to your brushes.
4. After washing your brushes, reshape them to a nice point or edge using your fingers.
5. When you get a new brush, it will have the hairs glued together with gum arabic.  Gently wash this out with warm running water before you start painting.  Don’t try to bend the hairs before you’ve washed it, as this can break them.
6. Brushes often ship in a plastic sleeve to protect the point.  Don’t try to put this back on as-is as you’ll end up bending hairs backwards.  If you’re travelling with your brush and need to protect it, cut the sleeve lengthwise with a pair of scissors and slide it onto your brush from the handle end.

Besides messing up the tip, there are three other ways brushes can get damaged:

1. Getting paint in the ferrule (the metal part that holds the brush hairs).  Dipping your brush all the way up to the ferrule in paint-y rinse water or resting your paint-filled brush with the tip “up hill” from the ferrule can cause paint to run back into the ferrule and dry between the brush hairs, pushing them outward and causing the brush to frizz or split. Solution: don’t dip your brush into your rinse water past the ferrule.  Get a brush rest that holds your brushes horizontally or tip-down or lay them on a rag.
2. Your brush is shedding hairs.  For natural hair brushes, the hairs themselves can rot which will cause them to break.  The glue that holds the hairs can also become damaged in natural and synthetic brushes. Both of these problems occur when brushes are put away wet in an airtight container, causing water to sit in the ferrule for extended periods. Solution: Store your brushes in a bamboo or cloth brush roll where they can continue to dry after you put them away, or just be really sure they’re dry before you pack them up. If you use travel brushes and put them away wet in the field, remember to get them out and wash and dry them when you get home.
3. Bugs eat your brush.  Clothes moths and dermestid beetles are two common household pests who like to eat animal hair such as natural hair brushes. Solution: Store your brushes in an air-tight container for long-term storage (after being sure they’re dry).

Things You Shouldn’t Do With Watercolor Brushes

Watercolor brushes are usually more expensive than brushes for other mediums, so it makes sense to save them just for watercolor.  Here’s some things you shouldn’t do with your best brushes:

1. Paint on watercolor ground.  Watercolor grounds are rough and abrasive. Use your cheaper synthetic brushes and save your nice sables. 
2. Apply masking fluid.  Use a cheap synthetic or a ruling pen for this.  Dip the cheap brush in dish soap before you begin and you’ll have a chance of being able to use it again.
3. Paint with acrylics, gouache, or oils.  Acrylic and gouache stick to brush fibers, and acrylics dry right onto them.  You want smooth, synthetic fiber brushes for these media, so you can more easily wash them.  For watercolors, you want hairs with texture that will hold more water.  Oil paint requires harsh solvents to clean up which will be hard on your brushes and could leave oily residue that will make them less absorbent. 

How to Clean Your Brushes

If you’re following the guidelines above and being nice to your brushes, cleaning should be a snap.  Just rinse them out with running water in the sink, reshape, and dry them point-down in a brush rack or horizontally on the edge of a table with the hairs sticking off the edge (to keep them from drying flat on one side).  

No Soap, Please!

There’s generally no need to wash watercolor brushes with soap, and in fact soap, and especially dish detergent, can dry out and damage natural hair brushes.  Oil-based soaps and products for human hair, which some people recommend, can leave oil or silicone residues in the brush which will make it less absorbent.  The goal of hair products is to make hair smooth and slick and protected from humidity – but we want our watercolor brushes to be fluffy and absorbent. Commercially-made brush soaps are usually formulated for oil and acrylic brushes. They have oils to help re-hydrate bristle brushes that have been cleaned with solvents – not necessary for watercolors. Soap coming out of your brush can also make weird streaks in the gelatin sizing on your watercolor paper. 

Saving Abused Brushes

If you were mean to one of your brushes, there is hope.  Here are some ways to repair damage.

1. If your brush is splayed or split, wash it very thoroughly in warm running water, concentrating on getting paint out of the area next to the ferrule.  Then squirt a drop or two of gum arabic onto the brush and comb it through with your fingers.  Reshape the brush and let it dry for two weeks to allow the hairs to “remember” where they’re supposed to be before rinsing out the gum arabic.  A cornstarch solution can be used instead if you don’t have gum arabic.

2. A bent point on a synthetic brush can sometimes be repaired by dipping the brush in very hot (just below boiling) water for 10-20 seconds then re-shaping with your fingers.  Don’t submerge the ferrule, as the hot water could melt the glue that holds the hairs in place.

3. If you used a brush for something you shouldn’t have, this is the time to break out the soap.  Use a mild bar soap such as Ivory, Fells Naphtha, or Master’s Brush Cleaner.  Work the soap into a lather and see what you can clean off with it!  Rinse super thoroughly when you’re done. 

4. Loose ferrules can sometimes be repaired with an application of super glue, or with heat shrink tubing (sold with electrical supplies).

5. If the handle is rotten or delaminated, it can be replaced with a piece of dowel rod, sanded into your preferred shape and glued in place using super glue or another waterproof glue or epoxy.

6. A bent hair or two sticking out from the side of a brush can be very carefully trimmed with small scissors or an xacto knife.  Cheap flat brushes with an uneven edge can also sometimes be trimmed with an xacto knife and a straight edge, although my results have been mixed.  Generally, it does not work to change the shape of a brush by giving it a hair cut, because good quality brush hairs taper to a point and have a slight curve which is aligned specifically to help the brush keep its shape.  When you cut them, this shape is destroyed and the hairs stick out weirdly.  On the other hand, if the brush is unusable, what do you have to lose!

7. If all hope is lost, you can always turn your brush into a “special effects” brush.  Artful trimming with an xacto knife can turn a flat into a “comber” or a scrubber for wiping out paint.  Scrunch a brush in masking fluid and let it dry to make an abstract “stamp” for applying random-looking masking fluid texture.

And there you have it!  Be kind to your brushes, and they will be kind to you.