Answers to some frequently asked questions

Carnauba wax vs. gel coat sealant

Carnauba wax Vs gel coat sealant,
which is better?

No one debates the need to seal and protect gel coat finishes but there is disagreement over how best to do it. Many will only use a natural carnauba wax but boat manufacturers are increasingly recommending only gel coat sealant. There are a number of valid reasons for this. While carnauba waxes may be fine for fresh water, sailboats, their durability is very limited in salt water, especially on powerboats. Combining the corrosive effects of salt water and the abrasion caused by the hull cutting through the water limits carnauba wax durability to 60 days or less. Above the waterline is not much better. Carnauba waxes start to melt around 150 degrees f. Direct and reflected UV and thermal radiation is literally melting the wax off the finish.

Synthetic sealant on the other hand, have better bonding characteristics than carnauba waxes, better abrasion resistance and melting points in the thousands of degrees. Synthetic sealant will outlast carnauba waxes and will typically produce a brighter shine. Sealant should last 180 days, even in salt water.

So why the debate? In the early days of recreational boating, enthusiasts often applied over-the-counter, automotive sealant to their boat's gel coat. Many of these sealant contained strong petroleum solvents and/or coarse abrasives which actually accelerated gel coat oxidation. These enthusiasts were applying a "protective" sealant to their boat only to have it quickly turn a dull, chalky white. No wonder sealant got a bad image among early boaters!

Rule No. 1:
Don't use automotive sealant or polishes on gel coat finishes. There are exceptions but if the manufacturer doesn't specifically recommend their product for gel coats, don't us it! Use only polishes and sealant that are designed for gel coats.

Another problem shared by both carnauba waxes and automotive sealant has to do with the very nature of gel coats. Gel coat is porous. Seen under a microscope, your boat's flat, smooth gel coat surface is millions of tiny holes! These holes, or pores, fill with microscopic grime; marine scum and salt crystals, which promote gel coat oxidation. Think of this oxidation as "plastic rust". The contamination in the pores is eating away the gel coat from the inside, filling the pores with a dull, chalk. As the chalk fills more and more pores, the entire gel coat surface will take on a dull, whitish finish. Carnauba waxes and automotive sealant do not remove pre-existing micro-contamination in the pores. Worse, they seal the contamination in place where it continues to oxidize from the inside, under the protective wax.

Rule No. 2:
Select a gel coat sealant that has some kind of micro-fine, cleaning or polishing agent (not a coarse abrasive) to remove existing contamination in the pores. Removing this debris and then sealing the surface with a gel coat sealant will greatly retard the oxidation process and add years to the life of your boat's finish.
Rule No. 3:
Always consult a Professional Boat Detailer if you’re in doubt about the type of soaps, cleaners, or sealant to use on your Boat
New Boat Maintenance Program

We offer a maintenance program for the new boat owner to start the boating season right. The exterior is polished to improve any minor flaws, and then a coat of Weather Shield sealant is applied to exterior gel coat surfaces. We also offer an interior vinyl guard package as well.

Maintaining the gloss of new or just-polished gel coats.

New gel coats and just-polished gel coats should be protected with either a synthetic polymer wax or a gel coat/Fiberglass sealant. Both offer greater protection and extended durability because they seal the pores from air (ozone) better than a store bought carnauba wax, as carnauba does not last on gel coat. If you use a store bought wax, you should plan on waxing your boat 6 times a year. If using a professional synthetic polymer wax or gel coat/Fiberglas sealant, plan on applying a protective coating twice a year.

What is gel coat?

In 1942, Owens-Corning developed a strong plastic laminate made with a cloth mesh core impregnated with a polyester resin. They called their new product Fiberglas.

Products made from Fiberglas, everything from a bucket to a boat hull, are made in a female mold. This mold has a mirror-smooth inner surface, which is sprayed with a mold release agent. This agent stops the resin from sticking to the mold and facilitates easy removal of the molded part. In the first step of the manufacturing process, a thick layer of resin, usually with a colorant added, is sprayed against the inner surface of the mold. This resin, which will become the outer surface of the molded part, is called the gel coat. Next, layers of resin-impregnated glass fiber mesh are built-up to a desired thickness.

When the resin hardens, the fabricated part is removed from the mold. The molded part is said to be made of Fiberglas but the smooth, glossy, outer surface is still referred to as gel coat.

Is gel coat clear coated?

It can be but it’s not the same as an automotive clear coat. In clear, gel coat finishes, the same resin is used for the first step but no colorant is added. The disadvantage of clear, gel coat is that discoloration of the inner layers will occur over time and the color can not be restored because it is under the top, clear, gel coat. Polishing can restore clarity to the top, clear, gel coat but can not restore faded colors under the clear, gel coat

Why does gel coat scratch so easily?

Actually it doesn’t. Gel coat is a very tough, scratch-resistant finish. The problem is that, regardless of the gel coats color, all scratches show up as white. This causes scratches to be visually highlighted.

Will scratches in the gel coat lead to failure of the coating?

.No. As long as the scratches are minor, it is a cosmetic issue. Scratches, blisters and peeling gel coats that reveal the inner cloth mesh are a different matter. These blemishes should be repaired before polishing is attemped

Cleaning gel coats.

Repeated use of strong acid cleaners, including oxalic acids, can penetrate into the opening pores. While this dissolves the chalk in the pores and gives the illusion of increasing surface gloss, it makes the gel coat even more porous. Eventually gel coat can become so porous that the gloss can not be restored by any compounding, polishing or finishing procedure.

Occasional use of butyl cleaners to remove diesel residues or other grime (spot cleaning) is generally considered non-injurious to the finish but do not allow these cleaners to dry on the surface. Black stains on the side of moldings can be safely removed using a citrus cleaner.

Routine cleaning should be done using any shampoo approved for washing automotive/marine/Fiberglass surfaces. Car wash shampoos are perfectly acceptable.

Do not use dish washing or laundry detergents.

Plastic rust! The gel coat aging process.

Exposure to ozone and ultraviolet light causes the polymers on the surface to gradually breakdown. Think of this oxidation process as "plastic rust". As the surface oxidizes, pores open in the gel coat containing oxidized resin molecules called "chalk". This chalk eventually turns the entire outer surface a dull, opaque color. Gel coat oxidation can be greatly reduced by keeping the surface sealed and protected using either a synthetic polymer wax or a gel coat/Fiberglass sealant.

Use of the proper product makes the deference! this is a 1993 boat that spends it's summer at 3 rivers, we have detailed it once a year for the last 16 years

FIBERGLASS BASIC MAINTENANCE
1992 Bounder before polishing

same 1992 bounder after

Custom Detail, Salem Oregon's Oldest And Most respected Boat and RV Detailing Expert since 1992, Expert Gelcoat and Filon polishing, restoration & protection, High performance - Custom - Classic Auto & Truck Detailing

Carnauba wax vs. gel coat sealant