(c) Caring for brushes. For the lettering brushes to perform
properly and have a long life, you must clean and store them properly.
All paints are not compatible with all thinners. Therefore, when you
clean the lettering brush, you must ensure the thinner is compatible
with the paint (figure 168). If you do not use the correct thinner to
clean the brush, you could ruin the lettering brush.
Figure 168. Paint/thinner compatibility chart
Proper cleaning and storage of lettering brushes help prolong their
life. After you have cleaned lettering brushes used in oil paints or
lacquers, fill them with linseed oil, shape the hairs, and place them on
their sides. Never rest brushes on their hairs.
An expedient way of storing a brush is to fill it with motor oil. The
oil prevents the remaining paint from hardening, which causes the
brushes to become useless. However, you must clean the brush and change
the oil after a month of nonuse.
A paint brush conditioner helps keep the larger brushes soft and pliable
(figure 169). The container and thinner also softens dried oilbased
paints in brushes. (The GSA supply catalogue details this container.)
You also can use mechanical lettering devices and prepared letters to
letter graphic projects. Both mechanical and prepared letters have the
advantage of producing uniform letters. Unfortunately, even the most
experienced illustrator cannot letter a