Creating shapes using masking fluid

Apply masking fluid to unpainted paper to create finely-detailed shapes.

Masking fluid (also known as liquid frisket), allows you to cover areas that you do not want to paint. Because the frisket is somewhat thicker and easier to apply than the watercolor paint, it can be shaped into detailed designs that would be difficult to create using paint alone.

There are several varieties of frisket available. Here is a good summary of the more popular brands. I prefer the masking fluid pens, as they are better for creating delicate shapes. For beginners or those on a tight budget, the tried-and-true fallback is rubber cement. But rubber cement tends to be a bit gloopy; it isn’t good for details.

The masking fluid is usually applied directly to the paper. You can use a brush to apply the masking fluid, but be sure to select a cheap one, not your expensive weasel hair brush. The manufacturer may claim that the frisket will wash out of your brush, but it probably won’t. After the fluid dries, paint over it and allow the paint to dry completely. Then remove the masking fluid using a putty eraser or beveled piece of wood. You can rub it off with your fingers, but the oil in your skin may smudge the paint.

Masking fluid is best used with 100% cotton paper. Lower-quality paper contains bits of wood and cellulose that tend to come off when you remove the masking fluid, creating rips in your painting.

It’s possible to apply the frisket to an already-painted area instead of directly to the paper. But some of the paint will probably come off when you remove the masking fluid. You may wish to let the paint and paper dry overnight before applying the masking fluid.

In the painting below, the dandelions were drawn directly on the paper using a masking fluid pen. The course texture of the paper lends texture to the dandelions. After removing the masking fluid, I added a very light bit of paint to a few areas using a dry brush. Some small, randomly placed dots added to the effect of a field of dandelions. This required a lot of planning: I had to decide where the dandelions would be before I painted them!