RV and Vehicle Paint Correction in Yorba Linda

Because you cannot see how much finish is left. A clear coat that looks identical across a panel may be 50 microns in one area and 110 in another, depending on how the vehicle was painted and how much correction it has already received.

A gauge reads total film build and, on comparative readings across a panel, shows where material is thin. Areas around edges, body lines and high points are always thinner, because they were sprayed with less and because every previous polish concentrated there. Those are exactly the places where correction burns through.

The practical rule is that clear coat failure is not correctable. Once clear begins to fail, showing cloudiness, a milky haze or lifting at an edge, the layer has broken down and abrading it removes what is left. Owners frequently arrive hoping polishing will fix that, and the honest answer is that the panel needs refinishing. This shop has two heated downdraft booths, so we can give that answer without it costing us the job.

• Comparative gauge readings across each panel before any machine work
• Edges, body lines and high points treated as thin areas by default
• Clear coat failure identified as a refinish rather than a correction
• Gelcoat thickness assessed by condition and by correction history
• Test section completed and evaluated before the whole vehicle is committed

Gelcoat is pigmented polyester resin applied into the mould as the outer surface of the laminate. It is far thicker than paint, typically several times the thickness of a clear coat, which is why aggressive correction is survivable on gelcoat in a way it is not on a modern clear coat.

It is also softer and it oxidizes rather than failing. Ultraviolet exposure breaks down the resin at the surface into a chalky layer that has to be removed mechanically. That is a compounding job with a genuine abrasive, not a polish, and on a badly oxidized coach it can take three machine stages: a heavy cut, a refining pass and a finishing pass.

The complication is that gelcoat has been removed every time the vehicle was compounded, and there is no reliable non destructive gauge for it the way there is for paint over metal. Assessment is therefore by history and by condition: how many times the vehicle has been corrected, whether the colour is starting to look thin over high points, and whether previous work has already gone through anywhere.

Decontamination first, because polishing a surface with bonded contamination drags that contamination across the finish and creates the defects you are trying to remove. Wash, chemical decontamination for iron and tar, then mechanical decontamination with a clay medium.

Then a test section. A small area is corrected using the least aggressive combination of pad and abrasive that will do the job, and the result is evaluated under proper lighting. That determines the process for the rest of the vehicle. Starting with the heaviest cut because it is faster removes material that did not need to go.

Then staged machine work. A cutting stage to remove defects, a polishing stage to refine the finish the cutting stage left, and on darker colours a finishing stage to remove the last haze. Then protection, because a corrected finish with nothing on it is unprotected and will degrade quickly in Southern California sun. Detail labor is posted at $95 per hour and correction is quoted against assessed hours.