Hand lay up
The hand lay up technique is the simplest way of processing UP-resins into
final products. It does not require extensive investment in equipment, takes
place at room temperature and is used for a wide variety of products. It is an
open mould process.
Hand lay up is suitable for the production of medium to large size products in
limited series lengths, such as covers for machines and installations, boat
hulls and decks, trailers, etc.
The hand lay up technique is also used extensively for mould making,
prototyping and development purposes. As the final result is directly
depending on the skills of the operator, well-trained operators are a
prerequisite. Operator costs constitute a large part of the total costs of
this processing technique.
Before starting the hand lamination, the mould is cleaned carefully and
release agent is applied to the mould. Subsequently the gel coat, if required,
is applied. Then layers of glass mat are cut in the required shape, put into
place into the open mould and saturated with polyester resin.
Glass mats with a weight of 450 gr/m² are mostly used as a standard
reinforcing material. Sufficient layers of glass mat are applied on top of the
gel coat, the number depending on the required laminate thickness of the
construction. One layer of glass mat results in a thickness of the finished
product of approx. 0.8 mm. In some cases woven glass cloth is used in order to
increase the mechanical strength where desired.
