Fibreglass Repairs

Fibreglass is an incredibly flexible material used in numerous applications ranging from yacht hulls to pond liners. Its exceptional mechanical properties such as tensile strength, stiffness, flexural strength and water impermeability make this material highly desirable.

To preserve its properties, it is imperative that any damage is promptly addressed and this article outlines an easy solution for repairing fibreglass surfaces.

Preparation

Fibreglass has long been used in numerous applications such as yacht hulls, surfboards, flat roofs and water tanks due to its excellent mechanical properties and impermeability. Although fibreglass offers numerous structural benefits when applied properly, its limits can sometimes be reached and cracks or other damage require repair in order to remain functional.

Cracked structures should always be closely examined when cracks or other forms of damage appear to assess whether they threaten their overall integrity, particularly where structural considerations are involved - for instance if there are exposed substrates.

If the damage doesn't impact the structure, cosmetic repairs such as polyester resin or epoxy gel coat can be performed for cosmetic reasons only. Before starting any work on this area, the damaged spot must first be thoroughly cleaned with an acetone-soaked cloth to remove dirt and debris that might interfere with its bonding process.

Laminating

Fibreglass is an ideal material for surface repair applications requiring a durable and strong solution, such as structural surfaces that have become damaged due to water ingress. Fibreglass repairs surfaces such as flat roofs, grp boats, surfboards, tanks and pond linings.

First step of a successful repair: inspect existing structures. Locate all areas of damage; depending on its severity, damaged structures could potentially require cosmetic or structural repair work.

Prior to beginning repair work, it is vital that all surfaces you will be working on have been meticulously cleaned using a dampened cloth saturated with acetone. Any dust or dirt left on surfaces could prevent bonding of new laminate sheets. Once this step has been accomplished, measure and cut a sheet from fibreglass matting sized appropriately to repair that area of damage.

Bonding

Fibreglass is an extremely flexible material, being used for everything from yacht hulls to flat roof coverings and pond linings. However, fibreglass has its limits; without proper repairs being performed on damage it could render structures unusable.





Fibreglass repairs First step to any effective fibreglass repair is sanding down the damaged area to a smooth and even finish, using a 12:1 taper so that it matches up as closely to original material as possible.

Once sanding has been completed, the repaired area should be thoroughly cleaned using a solvent to remove any contaminants and mix the resin according to manufacturer's instructions. Please also keep in mind that extreme hot or cold temperatures may inhibit curing speeds for polyester resin.

Finishing

Once your final coat of resin has set and hardened, sand to achieve a smooth surface and wipe clean before sealing it with a pigmented topcoat sealant.

Before beginning any fibreglass repair project, the most critical step should be assessing any damage thoroughly and considering its effect on structural integrity of a component.

If the damage affects mechanical properties, more in-depth work and replacement may be required; otherwise, cosmetic issues that do not compromise mechanical properties may be repaired with epoxy or polyester filler.