Ceramic Coating High Spots: How to Spot and Fix Them Before and After Cure

Ceramic coatings are applied in small sections, allowed to flash for a short time, then levelled and buffed with microfiber. Ceramic Pro's 9H product page lists a flash time of 30 to 60 seconds and a levelling and wipe-off window of about 60 seconds at 25°C and 50 percent humidity. Miss that window, or leave a thick ridge of product, and the leftover coating starts to harden in place.

IGL describes high spots as un-levelled coating that has cured or is in the curing stage. It names poor buffing as the main cause, along with uneven application, where the applicator carries more product in some passes than others. Heat speeds things up. Direct sun or a hot panel shortens the flash time, which is why coatings go on in a shaded, temperature-controlled bay.

Panel edges, badges and the area near trim gaps are common trouble spots because product pools there and towels do not reach it easily.

IGL says high spots look like darker patches or rainbow-looking streaks, and that they are easier to see in good lighting or outdoors on a cloudy day. Direct sunlight can make a coating look level when it is not. On lighter colors, IGL recommends a flashlight to reveal them.

Mike Phillips, writing on Autogeek's forum, describes finding a high spot on a coated 1962 Impala with a handheld swirl-finder light and notes that overhead lighting works for horizontal panels but a handheld light is better for vertical ones. The best habit is to inspect each panel under angled light right after the final buff, while the fix is still easy.

The sooner you catch a high spot, the gentler the fix. The windows below come from IGL's guidance for its own coatings; other products cure at different speeds, so check the maker's instructions for the coating on your car.

If you are not sure how far the coating has cured, start with the gentlest method and step up only if it does nothing. The full cure timeline is covered at Ceramic Coating Curing Time: When It Can Get Wet or Be Washed.

Once the coating is hard, wiping does nothing. Mike Phillips notes that a microfiber towel alone had no effect on the cured high spot he removed. He worked it off by hand with a soft foam finger pad and a one-step cleaner wax, then recommends chemically stripping the section a few inches beyond the worked area and reapplying the original coating per the maker's directions.

For a machine fix, use a dual action polisher, a soft finishing or polishing pad and a fine polish, and work only the affected area with light pressure. The goal is to remove the raised coating without taking off much clear coat. Phillips suggests using a body-shop-safe polish rather than a product with wax in it, because wax residue has to be stripped before you can recoat.

After polishing, wipe the area with a panel prep spray, apply a thin layer of the same coating, level it, buff it and inspect again under the same light. Keep a little of the original product for this reason. Phillips calls abrading and recoating the whole panel the most accurate fix, since a spot repair can leave a faint difference in gloss on dark paint.

High spots are mostly a technique problem, and the habits that prevent them are simple. IGL recommends inspecting immediately after application, using a wider and softer application block, working one small section at a time, and buffing in multiple passes: the first to remove the peaks, the second to level, and an optional third.

If you are paying a shop, ask whether they inspect under swirl-finder lights before release and whether they will fix high spots found in the first few days. Most reputable installers do this as part of the job. DIY owners should start on a flat, easy panel like the roof or hood before moving to bumpers and badges.