Car paint repairs and colour matching

What's in your car's paint

Most modern cars have three layers over the metal or plastic: primer, which bonds to the panel; the base coat, which is the colour; and a clear coat, the hard, glossy lacquer that takes the weather, the car wash brushes and the odd bird dropping. Some older cars and vans have single-stage paint, with colour and gloss in one layer.

None of it is thick. The clear coat on its own is thinner than a sheet of paper, which is why there's a limit to how often a panel can be polished: every pass takes a little lacquer with it.

Why depth decides the paint scratch repair

Scratches that stay in the clear coat are a polishing job: the lacquer around them is machine polished level until the light stops catching the edge.

Once a scratch reaches the colour, polishing has nothing to bring back. The area is sanded, painted and lacquered.

Down to grey primer or bare metal, the scratch needs building back up in every layer, with filler first if it's deep. On steel, sooner is better, because exposed metal rusts and the rust spreads under the good paint around it.

Depth matters at lease return too. The BVRLA fair wear and tear guide accepts surface scratches up to 25mm long, up to four per panel, as long as no primer or bare metal is showing.

Car paint repairs: small area or full panel?

Scuffed bumper corners can often be painted in just that area, with the new paint faded into the old. That's smart repair, which saves painting the whole panel.

It has limits. A key scratch running the length of a door needs the whole door painted, and probably blending into the panels either side. The middle of a bonnet or roof is hard to repair locally, because there's no edge or crease nearby for the eye to stop at. Dents, scuffs and chips are covered on our minor car repairs page.

How colour matching works

Every car has a paint code, a short mix of letters and numbers on a sticker or plate somewhere on the body, which identifies the colour.

The code is only the starting point. Paint made to the same code can come out a shade different from one factory to another, or one batch to the next, and paint suppliers often list several variants of a single colour for exactly that reason. Then there's your car: paint that has spent eight summers on a driveway isn't the shade it was in the showroom.

So the painter picks the closest variant and does a test spray on a card, then holds the card against the car in daylight and adjusts the tint until it sits right. That's normal bodyshop practice.

The last step is blending. Rather than stopping dead at the panel gap, the colour is faded out across part of the next panel, with lacquer over both, so any slight difference fades away instead of ending in a hard line. That's why a scratch on one door can mean paint on the wing as well. There's a longer explanation in how car paint colour matching works.

Metallic, pearl and three-stage paints

Solid colours are the most straightforward to match. Metallics carry tiny aluminium flakes in the base coat, and the way those flakes settle depends on how the paint goes on: gun distance, speed, air pressure, how wet each coat is. Get it slightly different and the repair can look right head-on but lighter or darker from an angle.

Pearl paints use mica in place of metal flake, so the colour shifts with the light. Three-stage paints, often pearl whites, add a see-through mid-coat between the base and the lacquer, and the number of mid-coats changes the final shade. These take longer to match and nearly always need blending, so expect the painted area to be bigger than the damage.

Fading and tired lacquer on older cars

On an older car, mixing exactly to the original formula can be the wrong answer. Sun fades paint, and some colours, solid reds especially, go noticeably paler over the years. A panel sprayed to the factory formula would look too fresh next to the rest, so the aim is to match the car as it is now.

Lacquer that has started to go cloudy or peel, often on the roof and bonnet first, is a different issue. A small repair next to failing lacquer won't look right for long, and if the whole panel needs doing, we'll say so.

Why a cheap touch-up pen often looks worse

Touch-up pens mixed to your paint code do one job well: a dab on a tiny chip on a steel panel keeps rust out until it's done properly. On a scratch, a pen usually makes things more obvious. The paint goes on thick and dries as a raised line. It hasn't been adjusted to your car's actual shade. Without a clear coat over it, it dries with a different gloss. And it all has to come off again before a proper repair.

Where we do paint repairs

All three bodyshops do paint repairs and colour matching: Basildon in Essex, Dartford in Kent and Sydenham in South London. Sydenham and Dartford hold the BSI Kitemark for Vehicle Damage Repair (BS 10125:2022), which is checked by independent audit, and at Sydenham the certified scope includes refinishing, the trade word for painting.

From Billericay, the Basildon workshop is about 15 minutes away via the A129 and the A127; see paint scratch repairs for Billericay drivers.

It's worth reading our Sydenham Google reviews, or the ones for Basildon and Dartford. To get a price, send us photos of the damage and the paint code if you can find it.