How to Remove oxidation From RV Fiberglass

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Fiberglass RVs do look very pretty, but not when they are covered with traces of oxidation.

Unfortunately, oxidation isn’t the easiest thing in the world to remove from your RV’s fiberglass surface. In most cases, water and automotive soap won’t suffice. However, it isn’t impossible either, unless the fiberglass has been severely damaged by oxidation.

Now, if you’ve been looking for a solution to your oxidation problem, maybe you will find the answer to your issue below.

Why does fiberglass oxidation happen?

To impart a smooth and shiny finish to RV fiberglass, it is coated with translucent or colored gel raisin material. Albeit durable, this coat is subject to fading as it weathers, as well as is subject to oxidation from sun glare, heat, and moisturized air.

To prevent oxidation, the gel coating is covered in wax. The wax itself eventually wears out, however, so it isn’t the ultimate solution for the prevention of fiberglass oxidation. Aside from that, inadequate care of the fiberglass may result in oxidation.

Extreme sunlight, excessive moisture, and air pollutants can quickly lead to oxidation. Due to this, you need to park the RV in a safe location, as well as regularly wash its surface. 

If oxidation has nonetheless started to damage your RV’s fiberglass look, then the tips below should help you restore its former look and shine.

How to remove oxidation from RV fiberglass?

Removing mild fiberglass oxidation

Mild fiberglass oxidation is relatively easy to deal with, but it will nonetheless require some effort from you.

With most light-to-mild oxidation cases, you will need to use a degreasing agent to help you with cleaning your RV’s fiberglass surface. That’s because when the fiberglass begins to oxidize and turns chalky, dust starts to stick to its surface. This results in the formation of grease on the fiberglass.

Using a degreasing agent is most convenient while washing your RV or Camper. Apply a degreasing agent to the wet surface of the fiberglass and rub it in. Depending on the degreasing solution you are using, you may or may not need to let it sit for some time. Once the required amount of time has elapsed, rinse the surface of your RV’s fiberglass.

Then, apply an oxidation remover to the fiberglass. Usually, these products should be allowed to dry and then peeled off to reveal a shiny fiberglass surface. Then, you may use a polishing compound to impart a better shine to the fiberglass.

Apply a polishing substance to the fiberglass and spread it with a buffer (whether power or manual). Some polishes contain abrasive substances that do a better job of removing oxidation, scratches, stains, and worn-out paint.

After you are done, you will need to apply RV wax to the treated area to protect it from outdoor elements.

Removing extreme fiberglass oxidation

Extreme fiberglass oxidation which has been caused by poor maintenance or RV aging is quite difficult to remove. Even professional products aren’t always able to deal with severe oxidation and make the fiberglass surface look like new.

Wet sanding is the best option for fiberglass oxidation that cannot be removed with other means. It essentially allows you to remove the top layers of coating that have suffered from oxidation. However, you should wet sand your RV only if you are 100% sure that no other product will help. 

Wet sanding is a time-intensive process, and you could easily damage the fiberglass surface of the RV if you aren’t careful. If you aren’t sure how to do it, take your RV to a professional.

Aside from that, if there are some other issues with your RV’s fiberglass paneling like deep scratches that reach the metal, wet sanding alone often is not enough. Oxidation could also span over multiple layers of coating, which doesn’t make wet sanding completely pointless, but it does make it much more difficult.

How to do wet sanding

To do wet sanding, you will need sanding paper, first of all. For light damage, finer 2,000-grit sandpaper should work well enough. For more severe oxidation damage, you may need to go for a coarser sanding paper with a grit size of 1,200-1,500, maybe even lower. 

Be mindful that coarser sanding paper (i.e. sandpaper with a lower grit size) poses a risk of scratching for your RV’s fiberglass surface. You thus need to be more careful when handling coarse sandpaper.

Soak the sandpaper in water

After you’ve got the sandpaper, you need to soak it in water for a period of around 24 hours. Some people also recommend adding a small amount of automotive soap to the water in order to prevent the sandpaper from burning the paint. If you do decide to use automotive soap, make sure not to use a polishing or waxing solution since you will do these things separately after getting done with the wet sanding.

You may want to prepare more than one sheet of sandpaper. Sandpaper gets worn out rather quickly, and for larger projects, you might need well over than just one piece of sandpaper.

Wash the RV

Before proceeding to the actual sanding, you need to wash the RV to remove any debris and obstructions from its surface. Use regular automotive soap with no polish or wax components to wash your RV. After you’ve thoroughly washed the RV’s surface, rinse it with a hose.

You don’t need to wait for the RV’s fiberglass surface to dry to move on to the sanding. The water will keep the sandpaper cool so that it doesn’t burn the paint.

Sand the fiberglass surface of the RV

You should wrap the sandpaper around a sandpaper squeegee, a handle, or a pad. If you use your hand or fingers to hold the sandpaper, you will create an unevenly sanded surface and an inconsistent finish. It is important that the sandpaper lie flat on the surface of the fiberglass.

Begin sanding the area with circular motions while applying little pressure. You want to start lighter in order to avoid damage to the RV’s paint, unless your goal is to remove it as well. If you find that the sanding doesn’t appear to affect the surface, apply a little more pressure until it does.

To ensure even sanding, switch the direction of the circular motion from time to time. Make sure not to change the pressure level on the sandpaper too much in order to avoid inconsistent sanding.

While sanding, don’t allow the sandpaper to become dry. Again, if this happens, you may burn the paint of the RV, which is a thing that you don’t want even if your goal is to remove the paint. 

If you find that the sandpaper is worn out or soggy to use, switch to another sheet.

And if you are using coarse sandpaper, you may want to repeat the process with finer sandpaper in order to remove any light scratches or abrasions left by the coarse sandpaper.

Rinse and allow the surface to dry

Once the treated surface is smooth to the touch, the sanding is complete. Then, you will need to rinse any soap and debris off the fiberglass with a hose. Make sure to do a thorough rinse – you want the surface to be completely free of any leftovers from the sanding since you will then need to apply a wax to the sanded area. 

While rinsing, touch the area to check if there is any soapy residue left behind. If there is, then you need to continue rinsing

After completing the rinsing, let the area dry completely. The fiberglass surface needs to be completely dry for further polishing.

Do not leave the RV under direct sunlight – no longer protected by any protective gels or waxes, the sanded surface can get easily damaged. Instead, place the RV in a shaded area for a couple of hours. You may use a towel or a hairdryer to speed up the drying, but you may need to wait longer to allow the remaining moisture to air dry completely.

Polish the surface of the RV

Now comes the time to polish the fiberglass surface. To do this, use a high-grade super duty polishing compound. You may apply the polishing compound with a buffer, or you may use a piece of soft cloth to apply it manually. The former is a quicker but a pricier option, while the latter doesn’t require too much money spent, but it does usually leave an uneven finish.

Some polishing products require 3-5 applications, so a buffer would be a preferable choice for polishing. If you don’t have a buffer, then it would probably make more sense for you not to buy one but take your RV to a body shop.

If you do decide to polish the RV yourself, follow the instructions provided by the manufacturer of the polishing compound. And when polishing, don’t apply too much pressure in order to avoid burning the paint.

Reapply the protective coating

After polishing, the fiberglass surface should look smooth and finished. Then, use an RV wax on the area to protect the sanded area from outdoor elements. Aside from that, waxing will impart a better shine to the fiberglass, as well as will level the sanded surface with the rest of the fiberglass.

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