Fiberglass lay-up is the most basic and
one of the longest used reinforced plastic
molding process. The mold design can be
male or female configuration, and the mold
surface is treated with a release agent that
will facilitate removal of the finished part.
A liquid gel coat of polyester, polyurethane,
or other resin is applied to the mold surface.
When the part is molded and removed, this
gel coat will form the exterior surface of the
part, a mirror image of the mold. Layers of
reinforcement and resin are added to build
the laminate to desired thickness. Lay-up
is suited to making large structures requiring
high strengths.

Fiberglass spray-up is a mechanized version
of lay-up. A spray gun simultaneously sprays
resin and chops continuous glass stands into
specific length fibers. Chopped fibers enter
the resin spray stream, and the polymer
composition is generally used to back up a
gel coat. The fiber-resin composition is rolled
out to effect complete wetting of fibers and
remove voids and bubbles before the resin
cures.


Fiberglass Machine Description
What is RTM?
What is RIM?