Ferrules
is the tapered metal tube that holds the brush hair filaments and are
designed for the basic shape and size of the brush. These are made of
different materials - aluminum, nickel, gold, satin, copper lacquered,
chrome, black chrome and nickel-plated. Seamless nickel-plated ferrules
usually appear shinier, with darker tone than aluminum. While
manufacturing, there is a high stress on its dimensional accuracy and
perfect surface finish.
Apart from the normal shapes like conical, cylindrical & fan,
ferrules also come in special shapes and in different sizes such as
curved, ringed, etc. Ferrules made of corrosion-resistant steel, brass,
and nickel, are designed to hold and reinforce the brush knot and
improve the brushes' appearance and add life. Brass, an alloy metal,
makes the strongest ferrules. Though sometimes left plain or with a
clear or gold colored coating, copper and brass ferrules are usually
nickel-plated for appearance and corrosion resistance. Aluminum ferrule
are much weaker but cheaper to produce and appear on lesser quality
brushes.
Quality brushes features a seamless ferrule, regardless of the metal
type. Ferrules with seams tend to pull apart and allow paint, solvents,
and water to accumulate, thereby causing loosening or damage to the
handle. In some brushes, a flexible natural or plastic quill is used in
place of a metal ferrule.
Brushes
used for acrylics have long handles that allow the artist to work at a
distance from the canvas. Acrylic paints are more caustic than oils, so
acrylic brushes are designed with synthetics and bristle. Acrylic
brushes are usable in other mediums, particularly oils, while brushes
designed specifically for oil painting and watercolors are unsuitable
for acrylics. Artists can very effectively use glazing and layering
techniques when using acrylic brushes.
Both natural and synthetic bristles can be used with acrylics,
depending on the artist's preference. But, acrylics, being alkaline in
nature, can be hard on natural hair brushes. Those made with high
quality synthetics have excellent durability and offers excellent
stiffness, snap and hair shape retention for maximum control. The
brushes must be kept clean. If acrylic paint dries in a brush it is very
hard to get out without using strong solvents that might damage the
brush. Brushes are cleaned promptly by washing them with warm water and
mild soap when finished painting.
