Detailing terms explained

Why a glossary helps before you call

Most owners learn detailing words one at a time, usually in the middle of a conversation about a problem. Someone says the gelcoat needs a heavier cut, or that the stainless should be passivated, or that the non-skid has loaded up with grime. The words sound technical, but each one describes something simple that you can see or feel on your own boat. Once you know the vocabulary, a phone call with a detailer becomes much easier because you can describe what you see and understand what is being suggested.

This page is organized by the part of the boat or the stage of the work. Surface terms come first, then the words for compounding and polishing, then protection products, then stains, metals, teak, decks, interiors and the terms used to describe how a visit is scheduled. You can read it straight through or jump to the heading that matches the question you have. Where a term is covered in depth elsewhere on the site, there is a link to that page.

One caution applies to everything below. A definition tells you what a word means in general. It does not tell you what your particular boat needs. Gelcoat age, past work, climate exposure, the slip location and how often the boat is used all change the answer. Quotes are given by phone only, and a detailer will often ask for photos or a short visit before suggesting a method. Use the glossary to ask better questions, not to decide the work in advance.

Surface and gelcoat terms

Gelcoat is the thin, colored resin layer on the outside of most fiberglass boats. It is the surface you see on the hull sides and deck. It is porous at a microscopic level and it slowly wears, which is why it needs washing, polishing and protection. Our page on how gelcoat ages explains the process.

Oxidation is the breakdown of the outer gelcoat layer from sunlight, heat and weather. It shows up as dullness first, then as a chalky white powder you can wipe off with a finger. The word chalking describes that powder stage. See chalky white gelcoat for what causes it and what a detailer does about it.

Haze is a general loss of clarity or gloss. A hazy surface looks like it has a thin film on it even after washing. Haze can come from early oxidation, from old wax residue, or from fine scratches that scatter light. Swirl marks are circular fine scratches, often from washing with a gritty mitt or buffing with a dirty pad. They show most under bright sun at an angle.

Pinholes and blisters are small defects in the gelcoat itself. They are not dirt and they do not wash off. Pinholes are tiny voids, and blisters are raised bubbles. These are repair questions rather than cleaning questions, and the page on gelcoat blisters and pinholes covers the difference.

• Gelcoat: the colored resin outer layer of a fiberglass hull and deck.
• Oxidation: sun and weather damage that dulls the surface.
• Chalking: the powdery residue that oxidation leaves behind.
• Swirls: circular micro-scratches from washing or polishing technique.
• Gouge or chip: damage that goes through the gelcoat and needs repair, not polish.

Compounding, cut and finish

Compound is an abrasive liquid or paste used to remove a thin layer of damaged surface. Polish is a finer abrasive that refines the surface after compound. A detailer might say a boat needs a compound and polish, meaning two steps: a more aggressive step to remove oxidation and deeper marks, then a gentler step to bring back gloss.

Cut describes how aggressive a product, pad or machine setup is. A heavy cut removes more material, faster. A light cut removes very little. You will hear a detailer say they will start with a light cut and step up only if needed. That is a sign of careful practice, because gelcoat is thin and every pass removes some of it. The page on gelcoat compounding explained goes through how many passes a surface can reasonably take.

Finish is the opposite end of the spectrum. A finishing polish and a soft pad leave a high-gloss surface with little or no visible marking. The finish step is what you actually see when you walk down the dock, and it is why a good detail looks deep rather than just clean.

Pad refers to the foam, wool or microfiber disc on the polisher. Wool pads cut harder, foam pads finish. Dusting and sling are the residues a product throws off during machine work; they are cleaned off before the next step. Holograms are faint cloudy trails left by rotary polishers when technique or pad choice was wrong, and they are corrected with a finishing step.

Protection terms: wax, sealant and coating

Wax is a natural or blended protective layer, usually carnauba based, that sits on top of the gelcoat. It gives warm gloss and some water repellency, and it wears away with sun, washing and salt. Sealant is a synthetic polymer product that bonds to the surface and typically lasts longer than wax. A ceramic coating is a more durable chemical layer that bonds to the surface and resists contamination and washing. All three protect the gelcoat; they differ in how long they hold and how they are maintained. Our comparison of wax, sealant and ceramic sets them side by side.

Water beading is the way water forms tight round droplets on a protected surface. Beading and sheeting are the quickest visual test of whether protection is still working. When water spreads flat and clings, the protection has worn thin. Cure time is the period after application when a product has bonded but has not reached full strength. During cure, the surface should stay out of rain, heavy dew, sprinklers and hose spray, and a detailer will tell you how long to avoid them.

Prep is the cleaning and decontamination done before a protective layer goes on. A coating over a dirty or oxidized surface locks the problem in, so prep is where most of the time goes. Topper or booster is a light spray product used between full services to refresh a coating or sealant.

Stain terms: tannin, bloom and tea staining

Tannin is a brown pigment released by plant matter. In South Florida waters it is common near mangroves and canals, and it stains hulls at the waterline as a brownish or yellowish band. Tannin stains often respond to mild acid based cleaners, but the right product depends on the surface. The page on waterline stain removal explains the process.

Bloom is a term used in two ways on boats. For gelcoat and paint, bloom is a hazy or whitish film that rises to the surface, often from moisture, cleaning residue or a cure problem. For vinyl and canvas, bloom can be a whitish film from plasticizers or mildew. In both cases the point is the same: it looks like a stain but is a surface film, and the first step is identifying which kind it is.

Tea staining is the brown discoloration that appears on stainless steel, especially near salt water. It is surface corrosion and contamination, not a sign that the metal is failing. See tea staining on stainless for details. Rust bleed is the orange streak left when iron from a fastener or a stray piece of steel runs down gelcoat. Rust stains are cleaned with products made for them and should never be treated with household bleach.

Mildew and mold are living growths that feed on organic residue, humidity and still air. They appear as black, green or pink spots on canvas, cushions, caulk lines and interiors. Algae is the green film that grows on damp decks and hulls, especially in shaded or low traffic areas.

Metal terms: passivation, pitting and bright work

Bright work is the older boating term for polished metal and varnished wood that is meant to shine: stainless rails, cleats, chrome fittings, aluminum trim and sometimes teak. The service page on bright work and metals covers the usual care.

Passivation is the formation, or the deliberate restoration, of the thin protective oxide layer that gives stainless steel its corrosion resistance. Stainless is not stain proof. It resists rust because of that invisible layer, and the layer can be damaged by salt, by contact with ordinary steel, by harsh abrasives or by long periods without fresh water rinsing. Cleaning followed by an appropriate passivating step helps the metal rebuild its layer. It is not a coating and it does not make the metal permanent.

Pitting is small crater-like corrosion on metal. Light surface staining can be cleaned and polished away, but true pitting means material has been lost. Polishing can make a pitted part look better without fixing it, so an honest detailer will tell you when a fitting needs replacement. The page on pitted chrome and stainless explains the difference.

Galvanic corrosion and electrolysis describe damage that happens when different metals are in contact in salt water, or when stray current is present. Detailers do not repair these, but they notice them, and a mention in a condition report is a reason to speak to a marine electrician or mechanic.

Teak terms: grain, two-part cleaner and sealer

Teak is the oily tropical hardwood used for decks, trim and swim platforms. Grain is the direction of the wood fibers, and it matters because scrubbing across the grain wears soft wood unevenly. Teak is cleaned along the grain with a soft to medium brush, never with a pressure washer. The page on avoiding pressure washer damage explains why.

Two-part cleaner refers to a pair of products, usually an acid based brightener and a cleaner, used in sequence on gray teak. The first step lifts the weathered fiber and the second neutralizes and brightens. Brightening is the name for that whole process. A two-part cleaner is stronger than ordinary soap, and runoff must be controlled so it does not stain gelcoat or enter the water. For the full method see teak brightening.

Sealer is a product applied after brightening to slow weathering and staining. Teak sealers vary in how they look, how long they last and how they feel underfoot. Caulk or seam compound is the flexible material in the seams between planks. When it hardens or lifts, water gets underneath, which is a repair matter and not a cleaning one.

Sticky teak is a residue problem, usually from an incompatible sealer, sunscreen, or oil based cleaner. It needs a stripping or cleaning step before anything new goes on, and the page on sticky teak decks goes through the causes.

Deck and cockpit terms: non-skid and scuppers

Non-skid is the textured pattern molded into deck and cockpit surfaces to give grip when wet. It is built from many small peaks and valleys, and dirt, sunscreen, oil and algae settle into the valleys. A non-skid that looks gray and feels slick may only be loaded with grime. Scrubbing with a stiff brush and a suitable cleaner, rather than polishing it, restores grip. Our page on non-skid deck cleaning covers the method. Never polish or wax non-skid, because that smooths the pattern and reduces traction.

Scuppers are drain openings that let water leave the deck or cockpit. Cockpit drains and hull drains serve the same function in different spaces. A detailer will usually check that these are clear, because blocked drains hold water and grime and raise the chance of staining and mildew.

Rub rail is the protective strip around the hull where it meets the deck, often made of rubber, vinyl or metal with an insert. It collects fender marks, dock rash and sun damage. Fender marks are the dark scuffs left by fenders and dock lines on the hull side.

Swim platform is the flat area at the stern used for boarding the water. It sees the most foot traffic, sunscreen, salt and sometimes fuel or oil, so it gets dirty quickly and benefits from regular rinsing.

Interior terms: headliner, bilge and humidity

Headliner is the fabric or vinyl panel on the ceiling of a cabin. It absorbs odors and can hold mildew if the cabin stays damp. Bilge is the lowest compartment of the hull, where water, oil and debris collect. A clean bilge is a sign of a well kept boat, and an oily or smelly one tells an owner something is leaking or needs attention. Detailers clean accessible bilges and report what they see; they do not repair engines or pumps.

Head is the marine toilet and the compartment around it. Galley is the kitchen. These two spaces are where sanitizing matters most, and the page on head and galley sanitizing describes what is covered.

Humidity control means managing moisture inside the boat with ventilation, dehumidifiers and air conditioning, because moisture is what allows mildew to start. Ozone treatment and odor neutralizing are methods used on persistent smells. They address the source only after the source has been cleaned, and they are not a substitute for cleaning. The guide to interior humidity control explains why prevention matters more than treatment.

Service and scheduling terms

Dockside means the work is done at your slip rather than at a yard. Most South Florida yacht detailing is dockside, subject to marina rules about water use, chemicals and contractor access. See dockside detailing marina rules for what marinas typically expect.

Wash down is a routine exterior wash and dry. Detail is a deeper, more specific service that can include polishing, metal care, interior work and protection. A wash down keeps a boat presentable. A detail restores and protects it. The article on detailing versus boat washing sets out the differences.

Haul-out is when a boat is lifted from the water for hull work, and post haul-out detailing happens when the boat is back at the dock with a freshly cleaned bottom, often with residue on the topsides. Turnover is the cleaning between charter guests. Recurring service is a standing schedule of visits.

Service call is the charge that covers a technician coming to look at a job that cannot be priced over the phone. It is explained on the phone before anyone is dispatched. Quotes are given by phone only, and larger jobs need an on-site visit first.

1. Look at your boat and name what you see using the terms above.
2. Take photos in daylight of the areas you are worried about.
3. Know which marina and slip the boat is in, and whether the marina has contractor rules.
4. Call and describe the surface, the symptom and how long it has been that way.
5. Ask the detailer to explain any term you do not recognize before agreeing to a visit.

Putting the words to work

A glossary is most useful when you carry it into a real conversation. Say what you see: chalky gelcoat on the port side, tannin line at the waterline, gray non-skid in the cockpit, tea staining on the rails. A detailer can start working out a plan from that description. They will ask a few more questions about how old the finish is, what has been used on it, and when it was last protected.

If you hear a term that is not here, ask. Good detailers expect questions and explain their methods. If an answer sounds like hype, such as a product that fixes everything or a coating that lasts forever, step back. Detailing is a mix of cleaning, correction and protection, and every one of those steps has limits.

If you are not sure whether a problem is a detail question or a repair question, say so. Chalking, haze, stains and dull metal are detailing matters. Deep gouges, blisters, soft decks, leaking hatches and corroded fittings are repair matters, and a detailer will tell you where the line is.

When you are ready, call the number on this page, describe the boat and the marina, and a person will walk through what a visit would involve and how a quote is arranged by phone.

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