Thursday, 5 May 2016

Restore and / or Refinish Gelcoat

Glass fibre (Gelcoat)

The outer skin of a fibreglass boat is sometimes called Gelcoat, a silica polymer (SiO2).the basis of textile-grade glass fibres, consisting of a glass thread less than 25µ (microns) thick, used loosely or in woven form as a reinforcing material in a very dense (hard) laminated plastic, also known as fibreglass (fibreglass). In most cases it is a relatively thin layer of high quality pigmented resin that gives the boat its colour. The very dense (hard) gel coat (405 – 450 µ) and its top coat (127 -152µ) helps to protect the layers of fibreglass.

After the mould has been cleaned and then highly polished as this affects the final finish of the gelcoat it is then waxed and sprayed with Mould release, and finally gelcoat is sprayed into the mould. Several coats can be applied after which the fibreglass chop is sprayed into the mould on top of the gelcoat and rolled out. Layers of fibreglass mat are then laid in to build thickness and wooden stringers are glassed in to strengthen the hull.

Gel coat has a vastly different formulation than automotive paint; it’s very dense (harder) much thicker and more porous. This means it usually requires a more aggressive abrasive than that required for clear coat paint.

Gelcoat fibreglass (polyester resin) is an ultra violet (UV) sensitive plastic. Though manufacturers add UV stabilizers in the manufacturing process, these protective agents weaken over time and must be replenished if continuing UV protection is desired

We all want the beautiful shiny new-looking boat, but we rarely get there because we assume it will cost us more than we're willing to spend. A new paint job seems like the only way, but a professional job is measured in thousands of dollars, not hundreds. Most of us would do it ourselves except we're not confident in our skills or have no experience with this sort of task. We ask for advice from others, but we are given conflicting accounts of the processes by everyone who seems to know more than us.

If the previous paragraph accurately describes you, then your hesitation is warranted. No single aspect of boat restoration is more littered with pitfalls, bad advice, and corner cutting than the refinishing. Additionally, no damage inflicted on a boat by the well-intentioned, but ill-equipped boat owner is as visible or costly as an improperly done restoration or refinish

Collinite Fiberglass Boat Cleaner -first step cleaner (prior to polishing) restores blemished fiberglass, restores neglected finishes affected by weathering

Shurhold Buff Magic - formulated with jeweller’s rouge to be a metal polish, as well as a buffing and polishing cream. This unique formula changes as you use it. With each pass of a buffer the proprietary abrasives in this diminishing compound break down. By varying the size of the abrasive a differing cut is obtained, so the more the abrasives are reduced in size the finer the resultant finish until the particles are reduced to a very fine powder, which in turn produces a burnished surface shine.

This effectively creates a compound that can work your finish from very dull to ultra glossy with just one product.  Additionally, since you do not have to switch products, this will save you time and money.  Removes: oxidation, gel coat stains, surface rust, tarnish, Plexiglas scratches and 1000 > grit scratches (Rotary speed 1000 – 12000 RPM)


Boat detailing can be a natural extension of auto detailing. Avoid washing your boat in the hot sun, always wash from top to bottom, and remember to rinse often. With proper care, you can keep your beautiful gel coat finish; do not use caustic, highly alkaline (high pH) cleaners or those containing ammonia

Surface stains may be removed by dish washing soap, mild cleansers or some household detergents. Chlorine and ammonia products can cause serious damage to the colour of the gel coat. If the stain is not removed by dish washing soap, mild cleansers, then the next procedure is to use either denatured or rubbing alcohol. Do not use acetone or other solvents to remove stains.

New proprietary restoration systems are available for boats that are on the last stages of the life of their gel coat. Apple Polishing, Island Girl, and other systems use cleaners that pull dirt out of the pores of gel coat and replace wax with special polymers that fill porosity and achieve a nearly new look. If your hull needs a total rehab, and you still don't want to repaint, investigate these products and see if any of them appeal to you.

Polishing Gel Coat

You need to use rotary polisher / wool pad combination to abrade gel coat, an orbital will not provide enough friction heat needed to restore gel coat. Gel Coat finishes are ~ 405 – 455µ (micron) (16-18 Mil) thick, and the top 5 to 6 mils is usually very dense (hard)

Meguiar's Heavy Duty Oxidation Remover removes moderate oxidation, scratches, stains and tough water spots on all fibreglass and painted marine or RV surfaces.

Meguiar's One Step Compound is an advanced aggressive, yet safe polishing compound that cleans and restores gloss on all gel coat surface in one easy step. It removes moderate-heavy oxidation, scratches, stains and tough water spots on all fibreglass and painted gel coat marine or RV surfaces. Restores colour and leaves a rich gloss on the treated surface. Meguiar's One Step Compound delivers incredible results by hand or machine.

I would recommend using a wool pad and cleaning it often with compressed air or a pad brush and using a fresh pad as often as is necessary

Klasse is an acrylic sealant and the original two-step paint care system. The first formulation was released in 1969. It was a breakthrough admixing polyethylene carnauba wax replacement system.
Through the years, Klasse car wax has evolved with many improvements. The first major change came in 1986, when Klasse was modified from its original formula to use the latest polyethylene-acrylic compound technology. Between 1991 and 1996, the chemists made incremental improvements to improve durability by more than 30% and U.V. protection by 100%.

Klasse All-In-One contains a chemical (solvent) cleaner that removes embedded dirt, light oxidation, which occurs when paint loses its natural oils, tree sap, road film and old wax plus it provides a tough acrylic protection. The foundation of the Klasse line this is a true one-step product. It cleans polishes and protects in one easy step. All-in-one is the first component of a two-part system; by adding the SG to the base coat of AIO it enhances protection, durability and the paints appearance.

Detailers Tips:

  1. Apply this product using water-dampened applicator, and then spray the applicator with Sonus Spritz.
  2. Apply Klasse products very thinly using absolute minimum pressure on the applicator.
3    Everything in a straight line, circular movements only add to swirl marks.
  1. Spray the vehicle surface very lightly with Sonus Spritz between each ‘layer’.
  2. Use a slightly damp 100% cotton towel to wipe the surface followed by a dry 100% cotton towel to remove Sealant Glaze
  3. I cannot emphasise ‘apply products very sparingly’ enough.
  4. Schnell-alternate: (Klasse Wash) Wash vehicle, apply "All-in-One" to entire vehicle while it’s still wet,  using damp 100% cotton towel, re-wash, rinse, and dry vehicle.
  5. As a quick detailer mix a 3:1 solution of Sealant Glaze and Sonus Spritz, spray onto a 100% cotton 
  6. Towel and apply lightly to pant film surface.
  7. The secret to the application of a polymer product is to apply it thin (super thin) fill a spray bottle and mist a foam pad for application.

Surface Preparation-
    • Wash with a good quality wash concentrate 1.0oz per 2 gallon
    • Using a long handled boars hairbrush with water hose attachment and a citrus based cleaner (P21S Total Auto Wash)
    • Rinse thoroughly.
    • Remove any imbedded contaminants with detailing clay (Clay Magic™) and a lubrication solution 5:1 (Distilled water/Woolite™)
    • Remove any surface imperfections with a suitable machine polish Or a swirl mark remover (3M™'s PI-III Machine Glaze)
    • Clean paint film surface with a pre-wax cleaner (P21S™ Gloss Enhancing Paintwork Cleaner)
    • Lightly wash paint surface with a diluted car wash concentrate 1.0oz per gallon
    • Dry thoroughly and start application process

Klasse All-In-One Application 

  • First and most importantly, thoroughly prepare your paint film surface.
  •   Wash, use detailers clay, polish and apply a pre-wax Cleaner
  • Shake product container vigorously to ensure mixing
  • Apply to a clean, dry surface away from direct sunlight
  • Dampen the applicator with water or use a lubricating spray during application
  • Place a small amount of product (about the size of a dime) on to a damp (but not wet) applicator (not the paint surface) apply a thin even film of product to paint surface.
  • If you are using a Porter-Cable orbital polisher to apply AIO, use a mild cutting foam (white) pad, using a low speed (3.5 – 4.0) and light pressure, let the polish / cleaners do the work.
  • Gelcoat does not dissipate heat as quickly as painted metal.
  • Apply to whole of one side of the boat (1-1.5oz of product should be sufficient)
  • Apply to vertical surfaces top to bottom and then left to right, on horizontal surfaces bow to stern and then left to right, over-lapping to ensure complete coverage.
  • This application technique affects the paints optical properties by optimising light refraction and the reflectivity of the bodylines and contours of the vehicle.
  • To test for results, wipe off product with a clean / dry Microfiber cloth. If the surface is still dull continue polishing, ensure that the product is worked in to obtain the best results.
  • Its primary catalyst is an aerobic process so for the acrylic to dry low air temperatures and/or humidity may affect the time requirement.
  • After sufficient drying time do a quick swipe test with your finger. If no smearing or drag is evident, the product is ready to be removed
  • Remove AIO as soon as it starts to ‘haze’ (set-up) this makes residues easier to remove than to allow the product to completely dry, and unlike wax, there is no benefit in doing so.
  • Residues should be slightly damp (not a dry powder) when you buff them. If the residues are still wet, you are using too much water on the applicator or too much product.
  • Removal: product can be removed with a 100% cotton cloth (Alpine DF™ Microfiber towel) or a with a Porter-Cable random orbital polisher and a non-cutting type (Grey) foam pad

Sufficient time should be allowed to enable cross-linking; 1-2 hours is recommended before the application of other products. 

Klasse High Gloss Sealant Glaze (SG) is a companion product to AIO that builds finish depth and clarity. It contains no cleaners, wax or polishes and can be layered. With each layer the gloss and depth of shine will increase and the tough acrylic protection will also increase.

The longer SG stays on the surface, the easier it is to buff off, if it is found to be difficult in almost every instance it can be traced to using too much product, applying with a dry, not damp, applicator and/or not waiting long enough before buffing. If there is resistance to easy buffing after its dry, simply mist the surface with any quick-detail spray and wipe with a dry Microfiber Cloth.

SG) Application Methodology:

  • Shake product container vigorously to ensure mixing
  • Do not dampen the applicator with water or use any lubricating sprays during application.
  • Apply to a clean, dry surface, with a temperature of >50 – 90
  • Place a small amount of product (about the size of a dime) on to a dry applicator (not the paint surface) and using a light to medium even pressure, apply a thin even film of product to paint surface.
  • As an alternative, pour some SG into small misting spray bottle, this will enable you to cover the applicator while using the minimum amount of product and this will ensure a super thin application.
  • Apply to one side of the boat (1-1.5oz should be sufficient) taking care not to apply to absorbent surfaces (i.e. unpainted plastics and rubber trim)
  • First pass:  apply (ultra- thin) roof to floor on vertical surfaces and across on horizontal surfaces
  • SG is formulated from hard resins and therefore must be given sufficient time to cross-link, >24 hours, but anytime up to 72 hour period is recommended before other layers / products are applied this provides better durability and a deeper shine
  • As air is the primary catalyst for the acrylic to dry, low air temperatures and / or humidity may affect the time requirements.
  • Residues should be dry when you buff them. If the residues are still wet, you are using too much product.
  • After sufficient drying time do a quick swipe test with your finger. If no smearing or drag is evident, the residue is ready to be removed.
  • Removal: product can be removed with a 100% cotton (Alpine DF™ Microfiber towel) or a with a Porter-Cable random orbital polisher and a non-cutting type (Grey) foam pad
  • Sonus Spritz is formulated the same way as Klasse and can be used to ‘even’ out layers or as a quick detailer
  • Second pass (ultra- thin) apply in direction of airflow, horizontal surfaces bow to stern, vertical surfaces front to back.                                                                                                
  • Third pass (ultra- thin) and any subsequent layer(s): apply in same ‘direction of air flow’ and leave on for 1-2 hours before removing residue
  • This application technique affects the paints optical properties by optimising light refraction, and the reflectivity of the bodylines and contours of the boat.
  • Finally spray a very thin layer of Sonus Spritz and buff with a 100% cotton cloth
  • ·         Sufficient time should be allowed to enable cross-linking, 12 – 72 hours is recommended

    Alternative products
    1.      Klasse All-in-one = Jeff Werkstat Prime
    2.      Klasse High Gloss Sealant Glaze = Jeff Werkstat Acrylic Jett
    3.      Acrylic Jett Trigger(AJT) a spray on version

    Meguiar's Professional Boat Detailing Products:

    1.      Meguiar's Flagship Premium Marine Wash is a gentle premium blend shampoo and conditioner enriches fibreglass and gel coat finishes, leaving a radiant shine
    2.      Meguiar's Heavy Duty Oxidation Remover removes moderate oxidation, scratches, stains and tough water spots on all fibreglass and painted marine or RV surfaces.
    3.      Meguiar's Hard Water Spot Remover removes tough hard water spots. The thick, low-drip formula remains on vertical surfaces for easy cleaning. New technology chemically embraces and lifts mineral deposits
    4.      Meguiar's Boat Polish creates a brilliant high gloss finish. It restores optimal gloss on fibreglass and painted marine or RV surfaces after cleaning. Plus, Meguiar's Boat Polish restores valuable oils to feed and nourish the fibreglass or painted surfaces. Especially effective on dark colours.
    5.      Meguiar's One Step Compound is an advanced aggressive, yet safe polishing compound that cleans and restores gloss on all gel coat surface in one easy step. Meguiar's One Step Compound removes moderate-heavy oxidation, scratches, stains and tough water spots on all fibreglass and painted gel coat marine or RV surfaces. Restores colour and leaves a rich gloss on the treated surface. Meguiar's One Step Compound delivers incredible results by hand or machine.

    Gelcoat Restoration

    Automotive paints and Marine paints are not interchangeable. Surveying the cosmetic condition of your boat has less to do with looks than it has to do with a chemically and mechanically solid foundation.

    Polishing Gelcoat
    This is the first step in restoring your boat's finish; if the gelcoat is thick enough and mechanically sound.
    Before discussing how to polish a boat, it's necessary to understand why. Obviously it looks nice.
    Shiny is not why we polish boats. Shiny is the lucky by-product of a safety and maintenance procedure that most of us are unaware is even necessary. A benefit definitely, but not the reason.

    Oxidation and UV damage.
    First, oxidation and UV damage are not the same thing and they don't have the same effect on a boat. Generally, we refer to both kinds of damage under the umbrella term “oxidation”, but it's important to know the differences between them. Technically, oxidation is a chemical reaction caused by exposure to oxygen resulting in the loss of electrons in the gelcoat. The result of oxidation is the chalking you see on the palm of your hand when you touch an unprotected boat. Sealing the gelcoat with a polymer protects the boat from oxidation.

    UV damage breaks down the binders in the resin used in gelcoat and leads to yellowing and an overall weakening of its mechanical structure. Polishing a gelcoat surface reflects ultra violet (UV) light. The more reflective the surface, the less UV penetration. The duller the finish, the more UV light will be absorbed.

    While oxidation only affects the surface, UV damage penetrates the full thickness of the gelcoat and can damage the fiberglass beneath it. Oxidation increases the rate of absorption of UV light because it reduces gloss (reflectivity). Conversely, UV exposure also increases the rate of oxidation by lowering the structural density of the gelcoat.

    This creates a parabolic effect where a degraded finish will continue to degrade at an ever increasing rate. In other words, a polished boat doesn't just look better than a dull boat, a polished boat will deteriorate at a slower rate than an oxidized boat. This is why you should polish and then seal the gelcoat.


    Polishing is the procedure of mechanically altering the smoothness of a surface. This is done by abrading the surface with successively finer grits of sandpapers and compounds until it becomes a glass-smooth, highly-reflective surface without any further coatings. When a new boat comes out of the factory, it's mirror-like reflection is not the result of wax or another coating. It is the result of mechanically polishing the mould prior to the boat's layup. It is a perfectly smooth surface.

    Polish the finish

    When a boat is in need of gelcoat restoration, I already have some idea of what it will take to bring the boat back to a factory finish. Even with years of experience I still advise a’Test Spot’ to avoid unnecessary trauma to the gelcoat.

    Acting too aggressively will take years off of the life of the gelcoat. When doing test spots, start with the invasive combination of pad / abrasive and finish that spot through the rest of the steps. Then do another test spot, start with the next mildest compound through to completion. Continue on with the test spots until no more improvement is seen between test spots. This is your starting point.

    Another factor is that levels of oxidation will vary with UV exposure. Horizontal surfaces with full exposure to the sun will be more severely oxidized than vertical surfaces exposed to only indirect sunlight. It is prudent to attack the more oxidized surfaced first and then continue to attack the entire boat with the next (milder) step in the process. The goal is to remove only as much material as is necessary to achieve the highest level of gloss.

    Wet Sanding

    Step one is wet sanding the boat. 800 grit wet or dry sandpaper and a soft foam block, will make quick work of the oxidation. Only use 800 grit if the boat is severely oxidized and you're sure the gelcoat is thick enough to withstand this aggressive paper. If you start at this stage, do not sand any corners or sharp edges with this grit. Save those areas for step two.

    Side note: For wet sanding, adding a few drops of liquid dish soap to the water will help lubricate the paper.

    After sanding, you need to remove all of the slurry, (the sanding residue), before moving on to step two. A damp rag will get most of it. Finish wiping off the boat with a rag lightly soaked in isopropyl alcohol (IPA). Sanding over coarse residue will give subsequent passes with finer grit paper an uneven finish as the residue will act like ball bearings under the paper.

    Cleaning the surface will also give you an opportunity to visually make sure you didn't miss any intended spots.

    When the boat is fully sanded and wiped off, wet sand again, but this time with 1000 grit wet or dry. You should expect to spend twice as much time sanding with 1000 grit as you did with 800 grit. This is to ensure you have removed 100% of the sanding scratches left by the coarser grit paper. This time, make sure to get all the corners and into the nooks and crannies.
    Follow this up by cleaning the surface again. If you missed any spots or you can still see sanding scratches from coarser grit, you'll need to go over those spots again. Successive steps will not remove them entirely.


    My preference for the tool needed here is a rotary polisher. The major factor in all of these tools is their working speed. Compounds and polishes intended for gelcoat recommend machine applications between 1500 and 2500 rpm. This is considerably slower than the working speeds for automotive compounds and polishes. The reason for this is because gelcoat is a much softer material than automotive lacquers and enamels, and, because of that, it builds up much more frictional heat (clean and/or change pads often).

    The heat generated by compounding a gelcoat surface has a direct effect on the compound itself. When you think of buffing compounds, think of them as liquid sandpaper. Essentially, it is grit floating around in a pool of solvents. As you buff the surface, the top layer is abraded by the grit. The particles of gelcoat are then emulsified in the solvents which then, by the heat generated from the spinning buffing pad, evaporates leaving the residue stuck to the pad.

    When you generate too much heat, the solvents evaporate too quickly. The dead layer of gelcoat doesn't have a chance to emulsify and stays smeared onto the surface giving you a hazy, blotchy finish. To add insult to injury, the excessive heat can burn the gelcoat resulting in a brownish discoloration of the surface.

    Initial pressure of between 20 and 25 lbs of downward force. That was for one or two passes around a 2'x2' panel and it was mostly done to spread the compound evenly. After that, my pressure lightened up dramatically to about 15 lbs pretty consistently. that was my base working pressure. Over the course of the next 45 seconds to a minute, my pressure steadily lightened to about 10 lbs (which is approximately the weight of the tool). After that, I eased off even more until I was just grazing the surface. That lasted anywhere from 10 to 30 seconds.

    I then take a clean flannel rag and hand polish any dust or residue off and inspect the panel. There should be even colour and no haziness. If it is necessary to redo the panel, I will add a little more compound and lighter pressure to even out the panel.

    Continue this way for the rest of the boats gelcoat surface. When the whole boat has been compounded, rag out the whole boat again. Make sure to look at it from all angles. Swirl marks and residue can be nearly invisible from one side, but stick out like a sore thumb from another.

    The next step is an abrasive polishing; my preference is Menzerna polishes. It works the same as compound but with lighter pressure all around. It is a much finer, more liquid polish and requires less mechanical force to be effective.

    For this, you should switch from the wool compounding pad to a foam polishing pad (my preference for pads are that mfg. by Lake County). The working speed is the same as the compound, just less pressure.

    After each 2'x2' panel, inspect the surface and buff off any residue with a clean flannel or microfiber rag. You'll notice that I added microfiber to this step, but not to the previous step. That's because the microfiber rag will get loaded with compounding dust and residue limiting its use before it's entirely too dirty, yet adds no appreciable benefit prior to the polishing compound.


    Congratulations! You have now successfully mechanically polished the gelcoat surface of your boat. The next step is seal the gelcoat to keep it from oxidizing and undoing all your hard work.
    Synthetic sealers don't add the depth or have the void filling characteristics of a good quality marine wax, nor do they have level of UV inhibitors found in good waxes, but they are very effective at sealing out oxygen on a long term basis. Much longer than wax alone.

    Wipe on a thin coat with a clean flannel rag and buff it off by hand with a microfiber cloth after about thirty seconds. Waiting too long with this product will leave streaks.

    Once the gelcoat has been sealed, a coat of wax will add depth and lustre to the finish as well as blend in minor surface imperfections.

    The wax I prefer is Collinite #885 Fleetwax, utilizing a wet-rag method. The instructions are printed on the can and they are not just a suggestion.

    The wax is applied using a damp rag that must be constantly turned over for each trip back to the can. The wax is then buffed out immediately while the wax is still wet. This is known as the wet-rag method and it's a trick used on hot days in direct sunlight for applying normal paste waxes. The moisture of the damp rag is used as a thinner to prevent the wax from solidifying too quickly. Wax that cures too rapidly makes buffing very difficult to do evenly. It is a testament the strength of Collinite's finish that it must be wet-ragged on, even in average climates.

    There are two downsides to Collinite's Fleetwax. The first is that it must be done by hand. Mechanical buffing is not an option with this wax unless you have a second person to either apply the wax as you buff right next to them, or vice versa. The second downside is actually a by-product of its quality; in some situations, it's too effective.

    I didn't mention this earlier and maybe I should have, but don't wax the non-skid areas of your boat. All wax is slick and safety should always be of paramount importance on the water. For non-skid areas, there are a number of sealers designed specifically for this purpose. They seal very well, have UV inhibitors, and designed for people to walk on.

    For most people, buffing and waxing a boat is an annual affair. If the boat is lucky, it might get a second coat at the end of the season, but most will never get that much.
    Carnauba is the only word people know when it comes to wax.  A marine grade polymerized waxes will outlast all others and still provide some level of protection throughout the year

    Other Products

    © All original material in these articles is copyright, unless otherwise stated, and may be copied and distributed for non-commercial purposes only as long as the source of the material is stated
    Always be willing to learn; because the more you learn, the more you’ll realize what you don’t know.
    It is said that knowledge is power, with the caveat that it includes access to a reliable information sources. I would like to think that these articles become an asset to anyone who is new to detailing and to professional’s alike, as well as industry experts who seek to advance their knowledge.

    I hope the article are informative. By having some understanding of the ‘What’ and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.

    I would appreciate it if you would share these articles as it helps other detailers further their knowledge.

    As always if you have questions, I’ll do my best to answer; bear in mind the only stupid questions is the one that was unasked. Questions and/ or constructive comments are always appreciated.

    Copyright © 2002 - 2013 TOGWT® (Established 1980) all rights reserved

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