Q. Whats the longest length of time I could safely leave masking fluid on good-quality watercolor paper before having to remove it? Im handicapped and cant paint every day; there are times when my masking may stay on for a week or longer.
A. If your studio space isnt too warm or dry, Id say it shouldnt be a problem to leave masking fluid on your paper for a week or so. After a time, though (and its difficult to say how long), the masking could discolor your paper. You might want to experiment with a scrap of watercolor paper: Put a stroke of fluid on the paper, then put the paper on a baking tray in a 150 F oven for a few hours. This will accelerate the aging of the material. If you can easily remove the dried fluid after, say, 4 hours in the oven (and it doesnt discolor the paper), then you can feel confident that applied masking will last for a week or so in your studio.
Albert Handell lives and paints in Santa Fe, New Mexico. He exhibits his work with Ventana Fine Art in Santa Fe, where he has had annual one-man shows since 1987, the Howard Portnoy Gallery in Carmel, California, and the Third Canyon Gallery in Denver. Several books have been published on his paintings and teachings, the most recent being Painting the Landscape in Pastel (Watson-Guptill Publications, 2000) by Handell and his wife, artist Anita Louise West.