How Do I Use Masking Fluid?
Tony Paul - Posted on 04 Mar 2009
Practical techniques for using masking fluid
There are many makes of masking fluid and even more makes of watercolour paper. The more absorbent the watercolour paper, the more likely it will be that the masking fluid will adhere to it or be, at best, difficult to remove without tearing the surface. Also, some masking fluids grip more aggressively than others.
Masking fluid rules
Always try out the combination of a new paper or masking fluid on a piece of scrap paper before committing it to a painting. Settle on a paper and fluid that work well together and see how long it is before the dried mask proves difficult to remove.
• Do not apply masking fluid to damp paper, or dilute it. It may adhere more strongly.
• Don’t try to speed up the drying process of either the masking fluid or subsequent washes with the over-aggressive use of a hot hairdryer. If you use a hairdryer, keep it very gentle.
• Remove the masking fluid as soon as possible. If you have applied the fluid but you find you are unable to start the painting in the near future, rub it off again and re-apply just before you start painting.
• In time, dry masking fluid breaks down into an inflexible, leathery scab that is immovable. How soon this happens depends on a number of factors. Don’t leave the fluid on the paper for more than a week. If its surface is no longer tacky, take it off quickly. It may already be too late. Remember, the longer that it is left on, the more difficult it is likely to be to remove.
• Masking fluid is best applied to naked paper. Applying it over dry washes can cause problems. Either the colour underneath lifts patchily or the paper’s surface pulls off.
Why use masking fluid?
Masking fluid saves us time. In my painting of the coal tit below, I wanted to create wet-in-wet washes as a background to the study of the bird. Cutting in around the bird would have been difficult so I masked out the bird and the branch it stood on with Daler-Rowney masking fluid. When dry it has a yellowish tinge, which is easy to see on the paper.
Some people use an old brush to apply the fluid (it will wreck a good one), but I prefer to use a Colour Shaper angle chisel, No. 0, firm (available from Jackson’s Art Supplies: 020 7254 0077, £2.59). This has a grey rubber pointed tip, looking rather like a brush. When finished, leave the masking fluid to dry on the Colour Shaper and then rub it off. LP
With a bit of practice, the finest lines are possible but you can also apply broad sweeps of fluid with the Colour Shaper. Here, you see the masking fluid applied and left to dry.
The first wash was applied, working over the dry masking fluid. Then the second wash was applied rapidly, wet on wet, over the first to give the effect of out-of-focus winter trees in the distance.
Twigs and branches, first in an ochre green then a purplish grey, were painted over the top of the dry washes. When these were dry, I rubbed off the masking fluid. It came off easily.
The few places where masking fluid had not covered the bird completely were lifted off with a damp brush and kitchen roll. I left others on the branch to help with its texture. The formerly protected area was now ready for painting.
The finished painting, watercolour, 7x5in. (18x13cm)
Further articles on the use of masking fluid click here.