Step By Step Process To Smooth Out Rough Fiberglass
Fiberglass, also known as GRP, for glass-reinforced plastic or FRP for fiberglass reinforced plastic, is regarded as a kind of plastic that is soaked or saturated with small glass fibers for reinforcement. Fiberglass is lightweight, strong when it comes to both compression as well as tension, and easy to mold into intricate shapes. Fiberglass was first introduced in the aircraft industry and has gained wide acceptance as a material for boat hulls, car bodies, and even residential construction since then. If you are looking to smooth out the rough fiberglass, then sanding it is one of the best options to consider. Go through the below-mentioned steps carefully to sand the fiberglass, which in turn will help smooth out the rough fiberglass:
- Clean The Fiberglass Panels
First of all, clean the body rigorously in order to get rid of any surface contaminants including grease or mold releases. A good wax, as well as a grease remover or alcohol with the help of clean rags or paper towels, should be used at first to clean the panels. One problem that you will encounter using a Scotchbrite pad with cleaners first is that it has a tendency to open up the pores in the gel coat that can allow some of the release agents to soak up into the fiberglass. Prevent cleaning like this due to the reason that it can cause imperfections in the paint down the road.
- Sand The Fiberglass
Now, sand the fiberglass before you start painting. It is important that the body panels are well supported, otherwise, there is a risk of distorting the panel with pressure from the sanding block. One of the best things about fiberglass is the gel coat finish, which will serve as an initial guide coat. You will need to sand the part as long as the gelcoat is moderately dull to give it enough tooth to take hold of the primer. The gel coat will display any low spots in the panels by remaining glossy, while the surface on every side of it will look dull.
- Dry Sanding Using 220-240 Grit Production Paper
Start by dry sanding with the help of 220-240 grit production paper in order to rigorously get rid of the glossy layer from the gel coat. Any areas that are still left glossy will not give the primer a tooth to bite into for adhesion. Be extremely careful to avoid sanding completely through the gel coat layer, which can open up pinholes in the fiberglass that can later show through the paint.
- Seal The Gel Coat With Fiberglass Resin Or Body Filler
If the gel coat is sanded through and the strands of the glass show, you need to seal it with fiberglass resin or body filler. Corvette panel adhesive is one of the best products in order to repair these areas. Repairs such as these always need to be sanded and blocked smooth before you lay down your first coat of primer. Any major repairs or alterations generally need extra procedures to achieve professional results.
- Apply Primer
The primer used should be consistent with the topcoats that you are using. If you are looking to use today’s modern base or clear coats, then urethane primers need to be used, which also applies to any single-stage topcoats. Remember, you can always go through the recommended procedure from your local auto body supplier. The primer needs to be wet sanded using 400 grit paper or finer to mate with the top coats being used. Be sure to rigorously dry and wipe down the surface using clean paper towels and do any extra cleaning with a final wash or wax and grease remover.