Rust repair using fiberglass is easy and can be executed by anyone who is willing to put in the needed effort. Fiberglass is a non-corrosive material that can be used as reinforcement or as a repair patch on almost all surfaces including metal, plastic, and wood. Typically, fiberglass is used for rust repair by replacing the rusted metal and sealing the surface. Fiberglass rust repairs are easily available at all local auto body supply store.
Preparing the Surface
Before using fiberglass, the surface should be prepared by washing the affected area with water and then cleaning it with a wax or grease remover. To ensure precision, you may apply masking tape to the surrounding to protect it when grinding the affected area of the metal surface. Having done that, apply metal conditioner with a clean cloth and use a separate cloth to wipe it off before it dries. This will prepare the surface of the metal for rust repair.
To apply the fiberglass-reinforced filler, place the needed amount of fiberglass to a mixing board. Next, mix the resin and hardener with a plastic spreader using a firm wiping motion. Once that is done, you will notice that the filler will begin to harden in a couple of minutes. Continue mixing the resin and hardener until the filler attains a uniform color. Allow the fiberglass-reinforced filler to harden and finally block sand with the use of a paper until the filler becomes level with the metal. In case the surface does not get leveled, you may layer another fine coat of filler.
In the presence of small rust-outs whereby rust has eaten through from the backside of the metal, a slightly different procedure should be followed to ensure rust repair. To prepare the surface, follow the same procedure as described above. Additionally, you can bevel the edges of the rust and paint scraps by using a pick hammer. Also, use a rust deactivator on the affected area to seal out any air or moisture so that oxidation is prevented.
Once the metal is prepared, close all rust holes with a fiberglass reinforced filler (waterproof). As directed above, use a plastic spreader to place the filler in the rusted holes and allow it to harden before smoothing it with a sand paper.
Large rust-outs or gaping holes are generally unattractive and can alter the structure of a metal body. Using fiberglass cloth patch and resin liquid provide an inexpensive means of rust repair. To apply the cloth patch, first apply a thin coat of filler on the repair area and on a piece of plastic cut to the size of the rust hole. Having done that, place the fiberglass cloth above the piece of plastic and put the patch, over the rust hole (fiberglass side down). With the use of a plastic spreader, even out the surface and press out all the air bubbles that may be present. Once the patch is firmly in place, remove the plastic. To complete the rust repair, apply a thin layer of fiberglass-reinforced filler over the cloth patch. If you need to paint the surface, here are some tips for painting fiberglass surfaces.
Rust is not just a cosmetic issue, it also affects the integrity of the item as well. Using fiberglass will help reinforce the strength of what you are repairing, so you don't have to replace it.