How To Polish Carbon Fiber Car Panels
The need to know how to polish carbon fiber car panels has become frequent with many cars now being constructed from this ultra strong, woven, man made material.
Not many cars yet have full carbon fiber bodies but it is often found in spoilers, aerofoils, roofs or hoods. In the quest to reduce weight and longevity carbon fiber is fast becoming the most used material
Generally used on everyday cars it is fast becoming the favoured material for the whole bodies of many major sport and performance marques.
With the strength equal or above most steel panels it is a superb option. But do we need to treat it differently with regards to polishing?
The answer is YES and NO, read on to find out.
2 Types of Carbon Fiber to polish
You are likely to find either:
- Bare Carbon Fiber
- Clear Coated Carbon Fiber
Bare carbon fiber is not usually found on outer panels (Except on race cars) it is often found on the interior or under the hood. This is carbon fiber in its natural state. Dull to look and the woven layers are easy to see.
Whilst this is not impossible to polish it can become a waste of time and some damage could occur due to the heat caused by friction of polishing. This type of carbon fiber is best left in its natural state.
Clear Coated Carbon Fiber is the most common type found on the front and rear aerofoils and often hoods.
This is carbon fiber that has had a few coats of clear coat applied to vastly increase the shine. Some of the items do have a gel coat applied as factory standard and little extra care must be taken with these.
Methods of how to polish carbon fiber
We have two choices to polish by hand or by DA polisher, just as we have with normal detailing of car paint. But with carbon fiber we do have an important issue to consider.
As mentioned the earlier there can be numerous layers of clear coat applied to the carbon fiber. Each coat is applied and left to dry before the next coat is applied.
As the next coat is applied there is a chance that some small pockets of air can become trapped between the layers.
Carbon Fiber Solvent Pop
This is termed as "Solvent Pop". It often appears as small white flecks or dots which appear to be within the carbon fiber woven layers. They are not easy to see at a distance but become ever apparent to the trained eye when close up.
These can cause problems if heat is generated whilst sanding the surface. The bubbles of air will heat up through the friction of sanding and try to escape from the layers. This can cause untold damage to the panel.
DA polishing is better for carbon fiber
Therefore care must be taken if hand polishing with grit paper as this is more aggressive and uneven than a DA polisher. Uneven pressure can cause deep grooves to appear in the clear coat. Also hand sanding causes many straight line scratches to occur. Neither of these are desirable or easily fixed so care is needed.
See the video below for more detail on these aspects as AMMO NYC really give great advice and alot can be learnt from the experts in this video.
How to Polish Carbon Fiber with a DA polisher
With hand polishing proving risky we would recommend machine polishing of carbon fiber. But as with all automotive polishing the surface has to be properly prepared.
1. Check the surface
Lightly rubbing your hand over the surface to feel for any protrusions is the first check to be made.
If any roughness is found then clay barring is almost certainly needed. To do this use a good clay bar and an ample spray of quick detailer. Work the clay bar over the surface in small circles. You will feel it lifting off the dirt, sap and other surface debris.
2. Sand the clear coat
Inspect the surface next and decide on the grade of grit paper needed. Use the most aggressive first. For example use 1500 grade to start with plenty of water added to the surface.
Then change to say a 3000 grade. It is recommended that you should spend double the amount of time on the finer grade that your spent on the initial one.
As an example:
1500 grade = 1 minute
3000 grade = 2 minutes
3. Polish to a shine
Use a polish combination such as these:
Use the Pro Speed Cutting compound for the first run through and then follow up with the Ultra Finishing Compound. This will take out the sanding marks gradually and polish to an extreme shine.
How to Polish Carbon Fiber with a DA Polisher
- Attach Pad to the backing plate of the polisher
- Dab around 5 spots of polish on the pad
- Work the polish into the pad. Try to get it to cover most of the pad with the least amount of polish.
- Spray a small amount of quick detailer onto the pad
- Place pad onto the panel
- Move the pad around without switching it on to spread the polish over the carbon fiber panel.
- Set polisher to a low speed (2) and move it around the panel
- Once totally spread over the area turn up to a medium/High speed and work it over the panel. Moving it at about 1 inch per second.
Polish then protect
Once you have polished the surface to a high shine you need to protect it. Just as we do with metal car body work.
The ideal product for this would be Chemical Guys Jet seal. It offers superb hydrophobic qualities and is ideal suited to smooth, swirl free, carbon fiber surfaces.
Jet Seal will seal in and enhance the superb shine of your carbon fiber. It also offers great UV protection which is important for carbon fiber as too much exposure can lead to a cloudy/ misty appearance in the fibers.
After applying it needs to be left on the panel for 20 minutes before polishing off and we find two coats is the optimum protection.
Carbon fiber is different in many ways to normal metal bodywork, and needs to be treated as mentioned.
It definitely seems to prefer machine polishing rather than hand polishing due to the multiple layers of clear coat.
Care must be taken with pressure being applied during the polishing process to avoid panel damage. Heat generation from the friction of polishing must also be considered as the process is carried out.
However, with care, time and good products a shine equal to normal bodywork can be achieved.
More and more cars will be featuring carbon fiber panels in the near future as the quest for reduced weight in electric powered cars is sought.
Knowing how to polish carbon fiber will therefore become more common and we hope we have prepared you for it.