Author: Boat Accessories Australia Date Posted: 19 August 2016
Gel Coat Explanation Blog
Gel coat is an integral part of any boat and over time can become scratch or damaged due to general use, accidents or improper cleaning and maintenance. Before attempting any repairs on your gel coat, it’s important to understand what it is and the proper steps to take to make it look as good as new again.
What is Gel Coat?
Gel coat is a special coating that goes over the fibreglass on your boat. It’s manufactured using an epoxy, polyester resin, a catalyst, and other chemicals.
It has little structural value but when combined with the fibreglass, it helps provide a smooth and durable surface that retards hull weakening from water intrusion and ultraviolet light.
The gel coat is usually applied first when the fibreglass mould is being created for the boat, so when it comes out of the mould it’s on the outside of hull. In many cases a pigment will be blended with the gel coat to give the boat a coloured, glossy surface.
Different Types of Gel Coat
There are two different types of Gel coat:
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| General Purpose Gel | Tooling Gel Coat |
Avoiding Premature Gel Coat Aging
Caustic cleaners or products containing bleach can age gel coat fast so make sure to minimise the use of these or rinse your boat well afterwards.
Abrasions can make any boat look old, and using a stiff-bristle brush on glossy surfaces like gel coat can eventually scrub their gloss away. Use a soft bristled brush, sponge, or rag to clean anything aboard your boat that’s smooth and shiny.
UV damage can take colour out of gel coats and this can happen a variety of ways, one being via the gel coat having an uneven surface where peaks and valleys have been created by on the coat to expose more surface to the sun’s radiant energy than a smooth surface would.
| UV-Damaged Gel Coat | Cracked Gel Coat |
Proper Care & Maintenance - Compound
A cutting compound can be used to remove a very thin layer of the coat to smooth out light marks and scratches and in turn allowing contaminants to wash away easier. Follow up with thorough wash downs after every outing using a boat soap such as Peter G’s Marine Wash. If the gel coat looks old chalky, and dingy, rejuvenate it with an anti-oxidation agent such as 3M’s Finesse-It II Glaze.
Yellow water stains can be removed with 3M Fibreglass Cleaner & Wax. If your coloured gel coat is needs reviving, contact the manufacturer to find out what brand of gel coat was used and if it can be helped. In many cases, coloured gel coat can be wet-sanded until it shines like new, but some brands will just be harmed more if you hit them with sandpaper.
| Gel Coat Before Compound | Gel Coat After Compound |
Proper Care & Maintenance - Gel Coat Fillers
Over time your fibreglass boat may end up with a scratch, nick or gouge in the finish. You can usually fix these yourself though repairing textured surfaces like diamond nonskid or multitone finishes should be left to professionals.
You will need to fill deep gouges with a resin and filler such as the Septone Gel Coat Repair Filler that should be used in conjunction with the Septone Gel Coat Hardener to cure to a white finish.
| Septone Gel Coat Repair Filler | Septone Gel Coat Hardener |
Proper Care & Maintenance - Restorers and Waxes
Keeping gel coat coated with wax is the best way to prolong its life. Regularly waxed gel coat can retain its gloss for 15 years or more. The real purpose of a coat of was is to protect, but wax also has restorative properties if the gel coat is not too badly weathered.
Restorer formulations renew the gloss in essentially the same was as wax but without the need for buffing. Resotrer kits, such as the 3M three-step range, typically include a prep wash and sometimes a polish in addition to the restorer.
For more information on gel coat maintenance, head to the Gel Coat Repair section on our site to find all the products you need to make your vessel look as good as new.
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