What is on your paint
Most paint problems look like one problem in the shade and six different ones in direct sun. Here is how to tell them apart, and which of them polishing actually fixes.
Six things that are not the same thing
- Swirl marks
- Fine circular scratches in the clear coat. They show up as a spiderweb when direct sun hits a panel and disappear again in the shade, which is why most people find them at a petrol station rather than at home. They come from dirt being dragged across the paint: a wash mitt that picked up grit off the lower panels, a towel used dry, or the spinning brushes at an automatic bay. Polishing takes them out, because the scratch is shallower than the clear coat is thick.
- Water spots
- Round chalky rings, worst on the hood and the roof. Rain or hard water dried on the panel in the sun and left its minerals behind. Caught in the first few days they come off with a polish. Left through a few more hot afternoons they etch a shallow dish into the clear coat, and then they need the same work as a scratch.
- Oxidation
- A whole panel going flat rather than a mark in one place. The colour looks chalky and slightly grey, worst on the roof and the hood where the sun sits longest, and a clean cloth run over it picks up a faint residue. This is clear coat that has gone years without wax on it. Polishing brings the colour back, and wax is what stops it returning.
- Etching from droppings and sap
- Small dull craters, usually scattered rather than in a pattern. Bird droppings and tree sap are acidic and eat into the clear coat while they dry, which is why the mark is still there after the mess has been washed off. Shallow ones polish out. Deep ones have gone through the clear coat, and at that point the panel needs paint.
- Holograms
- Straight hazy bands instead of circles, almost always on a car that has been machine polished before. They are buffer trails, left when a rotary was run too fast or with a pad past its best. A slower pass with a finishing pad removes them.
- Deep scratches
- Run a fingernail lightly across it. If the nail catches, the scratch has gone through the clear coat into the colour underneath, and polishing will not remove it: polishing works by levelling the clear coat down to the bottom of the scratch, and there is not enough left to level. That is a body shop job, not a detailing one, and we would rather say so on the phone than at your gate.
- Five of the six are in the clear coat
- Polishing works by levelling the clear coat down to the bottom of the mark, so a scratch shallower than the coat is thick comes out. That covers the swirls, the spots caught early, the flat panel, the shallow craters and the buffer trails.
- Shape tells two of them apart
- Circles are dirt dragged across the paint. Straight bands are buffer trails, and almost always on a car that has been machine polished before.
- The last one is drawn in section
- If your fingernail catches in it, it has gone through into the colour and there is not enough coat left to level. That is a body shop job, and we would rather say so on the phone than at your gate.
Two tests that settle most of it
- The fingernail test
- Drag a nail across the mark. Catching means it is through the clear coat. Smooth means polishing has something to work with.
- The angle test
- Pull the car into direct sun and look ALONG the panel rather than down at it. Swirls and holograms only appear at a low angle, which is why a car can look perfect in a carport and poor in a car park.
If you are still not sure which one you are looking at, send us a text and describe what you can see. We will tell you whether it polishes out before anyone books anything.
Where this work happens
- Interior & Exterior Detailing polishing, wax
- Home Service Car Wash the wash that does not cause them
- Windshield Buffing the same idea, on glass