Fiberglass is more frequently used in sports cars where weight is a consideration.

This lighter weight material can offer numerous advantages over conventional automotive materials. One advantage that might not be obvious is the ease and durability of repairs.

Because many lack the knowledge to repair composite parts and molds, damaged items are often replaced.  The process may seem intimidating at first, but fiberglass parts are often easier to repair than parts made from traditional materials.

Fiberglass is the foundation of the composites industry. It has been used in many composite applications since the 1950’s and its physical properties are well understood. It is lightweight, has moderate tensile strength, and is easy to handle. Fiberglass is used in a wide assortment of projects within the industry.

Automotive fiberglass resin requires fiberglass mesh fabric and a catalyst.  Fiberglass resin and mesh can be used to patch holes in automotive body panels and maintain the required rigidity for a body panel.

There are several types of glass cloth you’ll see at body repair shops, plus resins with and without epoxies.  These are matt mold, standard woven cloth, chopped glass, SMC, and polyester resins.  Glass cloth comes in varying grades (thicknesses).

Matt mold is often used for body work because of its random pattern.  It won’t leave a noticeable ‘weave’ in your paint finish.  Woven cloth is primarily used for building up structure or splicing sections of products made of the same material.

Although woven cloth has better strength and crack resistance, matt mold gives auto body technicians an advantage of being able to work areas without the fear of sanding down to the visible weave of the woven cloth.

Ideally, a repair is made by using woven cloth and then using matt mold to cover the repair area.  Bodywork always requires that the repair be blended into the surrounding area.

A deep depression must to be sanded wherever the woven cloth is to be used. Because of this, automotive body workers use matt mold for much fiberglass repair work.   They get the strength they need by using an adequate thickness.