Article by Capt. Steve Katz
Shine on!
New boat, old boat, painted boat, gelcoat boat: one thing in common is that they all need care and maintenance on their exterior surfaces to maintain the shine.
Most boats are built from fiberglass, in a mold on a production line. The fiberglass is bonded to itself and the boat with a resin, usually polyester, vinyl ester or epoxy - resulting in a fiber-reinforced composite. On top of this rough fiberglass composite is the topcoat, usually gelcoat in most production boats and often paint for custom built boats.
What is gelcoat?
Gelcoat is the outermost layer of resin, traditionally applied inside of the boat's mold as the first step of the boat building process. Gelcoat is usually sprayed as a liquid into the empty boat mold in multiple thin layers, resulting in a cured finish thickness of 0.01 in to 0.03 inches – not very thick! The chemical components have a natural color that would not be appealing for a boat, so a pigment or color is added to the gelcoat, often for the entire thickness of the gelcoat.
Gelcoat is a polymer-based resin and is cured by a chemical reaction of the components mixed before application. After curing in the mold, the boat building process continues with the fiberglass reinforced composite materials until the boat is a stage it can be pulled from the mold. Once this happens the exterior finish is complete, shiny and protected from damage throughout the boat building process. While modern gelcoat finishes are reported to be Ultraviolet light (UV) resistant, most boat owners know that even after one season outdoors, a new boat’s finish can start to look dull.
Clean, Polish & Protect
While a new gelcoat finish may look smooth, a microscope would show roughness and pores in the surface. These microscopic voids can retain dirt and stains. This combined with the effects of sun, salt and water result in a surface that can quickly dull.
In order to bring back the shine to your boat, or to maintain the shine you have, you will need to follow a few steps. If you are wondering if your boat's finish can come back to its original shine, run some fresh water over the boat's surface, if the color and shine look good when wet, you should be able to restore the finish. If the finish is beyond restoration, painting and or re-gelcoating may be a solution.
Cleaning
Cleaning with soap and water is a good start to restoring the shine to your boat, there are other details that need to be covered in this stage. Stains need to be removed – using the least damaging product. Sometimes just lemon juice can remove a simple stain that has discolored the finish, if not a harsher stain remover designed for gelcoat may be needed. Try to avoid strong chemicals like acetone, acid, or bleach-based cleaners to wash gelcoats, as these types of chemicals can weaken the gelcoat. Always start with chemical stain before resorting to harsh abrasives that can scratch or remove too much gelcoat.
Polish
Now that you have a clean stain free surface, you can begin to polish it in preparation for the wax coat. The top wax coat is only as good as the gelcoats surface – so this is where you will spend most of your time and elbow grease. The results of this stage is the finished product, minus the shine and UV protection- so if you don’t think it’s good enough – don’t rely on the next stage, it won’t help – take your time and get this right.
This step is required to remove the oxidized top microscopic layer of gelcoat that has become dull, remember the gelcoat is only so thick, so do not remove any more of the top layer that is necessary to restore the shine.
Polish is actually a fine abrasive or in the case of a compound a coarse abrasive. If you are not an expert, you may not know what products to use or how to apply. There are a multitude of rubbing compounds and polishing materials both in liquid and paste and can be applied by hand or with a buffer/polisher. Each boat's finish is different and may require different products, even on the same boat in different areas. Starting off with the least abrasive product is best, usually a polish. Often an electric buffer or polisher is a good way to speed up the process on a larger boat, smaller boats can be done by hand with good results. If the light polish does not cut away enough of the oxidized layer, increase the coarseness of the product – often moving up to a rubbing compound. Most marine detailing products offer a system of cleaning products with detailed description on their coarseness and use.
When it comes to electric buffers and polishers there is a myriad of choices- high speed, random orbit, wool pads, foam pads and more. If you are not sure, learn from an expert or review the information provided by the polish/compound manufacturer, they often have specific application instructions that even detail the speed and type of mechanical application method. Be careful, a mechanical application can easily go too far and too fast , burning or eroding the finish if care is not taken.
Once you have accomplished this stage, you should have a boat that shines brightly when the surface is wetted with fresh water. This stage may also show surface imperfections or damage, such as chips and scrapes. These should be fixed now, a deep scratch can let water or moisture into the fiberglass below the gelcoat, weakling the structure. Small imperfections can be filled with a DIY gelcoat repair kit and larger areas may require professional repair to match the shape, thickness and color of the original finish. Matching gelcoat colors is truly an art, often involves mixing from a color palled on-site until just the right shade is formulated, Even the original factory color may not match a few year old boat due to fading in the sun, Companies like Spectrum Color offer a rainbow of colors, some advertised to match a factory color.
Wax
Now the surface is the best it can be, it’s time to protect it. Wax was and still is the most common gelcoat protectant. These topcoats are like sunscreen for your boat, though now there are new polymer sealers and ceramic products that can also protect the surface like wax but better. Traditional paste waxes will fill the microscopic voids in the polished gel coat and usually contain oils that bring out the original color and add to the shine of the gelcoat.
How to choose the top coat product- you can't go wrong with a wax, you can apply multiple coats to better protect the surface– depending where and how you keep your boat a wax may last as little a few weeks or 6 months – but probably not much longer. Applying another coat of wax before the existing coat begins to wear will continue to extend protection indefinitely– avoiding backpedaling into the polish and correction stage.
Polymer sealers and ceramic products – it seems there are new products introduced every day to this marketplace and there are major differences in the chemical composition and application requirements.
In general, these products last longer and often provide a better shine than traditional waxes. If you plan to do this yourself be sure to read all about the product. An example: if you protect a surface with a solvent-based polymer sealant and apply a second coat, the second layer will dissolve the first coat, it's designed to be a one coat product. Ceramic coatings provide a much higher durability than wax or sealants. They resist heat, UV rays, environmental contaminants & harsh detergents much better than wax or sealants. While wax sits on top of the finish’s surface, a ceramic coating creates a chemical bond to the surface.
No matter what you choose as your protective coat, the details and hard work is in the cleaning, polishing, buffing and correction stage. The wax, sealant or ceramic is there to protect your hard work. Be sure to learn about the nuances of these specialty topcoat products-there may be benefits for you and your boat.
While cleaning, polishing and protecting the boat's finishes may not be as much fun as fishing, the hard work will be noticeable every time you get onboard and will help to keep the boat looking good in the year to come.
Until next time ...
Keep it clean!
