“It’s only a dent” can mean a two-hour job or a two-week one. The difference isn’t how big the damage looks, it’s what kind of damage it is and which repair method it needs. Here’s a plain-English guide to how car body damage is actually fixed, from the smallest scratch to structural repairs.
Scratches: it depends how deep they go
Car paint is built up in layers: primer, a coloured basecoat, and a clear lacquer on top. A light scratch that only marks the lacquer can often be polished out, with no painting needed. Once a scratch goes through to the colour or down to primer or bare metal, polishing won’t fix it. The area needs to be prepared, filled if necessary, and repainted so the layers are rebuilt properly. A quick test: if your fingernail catches in the scratch, it’s likely too deep to polish.
Dents where the paint is intact
If a panel is dented but the paint hasn’t cracked, paintless dent repair is often the best option. Specialist tools are used to gently push or pull the metal back into shape from behind or through access points, keeping the original factory paint untouched. It works best on smooth, shallow dents away from panel edges.
Dents and creases that need more work
Sharper creases, dents on edges or body lines, and any dent where the paint has cracked usually need a conventional repair. The metal is pulled and worked back as close to its original shape as possible, then a thin skim of body filler is used to get a perfectly smooth surface. Filler is meant to be a very thin finishing layer, not a way to fill a deep hole. From there, the area is primed, painted and lacquered to match.
Plastic bumpers and trim
Most bumpers are plastic, and many cracks, splits and scuffs can be repaired rather than replaced. Cracks can be reinforced and welded from behind, then refinished. If the plastic is badly torn, the mounting points are broken, or there’s sensor damage, replacing the bumper is often the better choice. Our guide to bumper repair vs replacement explains how we decide.
When a panel needs replacing
Sometimes a panel is too badly damaged to repair well, or repairing it would take so long that replacing it makes more sense. Bolt-on panels like doors, bonnets and wings can be swapped relatively easily. Welded panels, like rear quarters, need the damaged section cut out and a new one welded in to the manufacturer’s method, which is more involved but still a routine job in a properly equipped body shop.
Structural damage
A heavier impact can move the car’s underlying structure, not just its outer panels. You might not see it, but it can show as uneven panel gaps, doors that don’t close properly, or the car pulling to one side. Structural repairs start with measuring the car against the manufacturer’s data to find out exactly where and how far it has moved. It’s then pulled back into alignment, and any damaged structural sections are repaired or replaced following the manufacturer’s procedures. This is the kind of work where the BS10125 standard really matters, because it sets out how these repairs must be carried out and checked.
Getting the paint right
Almost every repair ends with paint, and a repair is only as good as its colour match. Factory colours vary slightly between batches and fade over time, so the paint code alone isn’t enough. We read the actual colour on your car and mix to match it, then usually blend the new paint into the neighbouring panels so there’s no visible line. Our article on how paint matching works explains the process step by step.
Why one “small” repair can involve several methods
A single car park knock might need a bumper repair, a paintless dent repair on the wing next to it, and paint blending across both. That’s why an in-person assessment is so useful: it lets us choose the right method for each part of the damage rather than applying one approach to everything. If you’re curious about what happens once the car is booked in, we’ve explained that in what happens to your car after you drop it off.
FAQ
Is body filler a bad sign?
Not when it’s used properly. A thin skim of modern filler over correctly reshaped metal is a normal part of a quality repair. The problem is thick filler used to cover metal that hasn’t been straightened.
Can all dents be fixed without painting?
No. Paintless dent repair only works when the paint hasn’t cracked and the dent is in a suitable position. Sharp creases and edge damage usually need conventional repair and paint.
How do I know if the damage is structural?
You often can’t tell from looking. Uneven gaps, doors or boot lids that don’t shut cleanly, or a change in how the car drives are warning signs. A proper assessment will check.
Is SMART repair the same thing?
SMART repair is a term for small, localised repairs. It’s great for some minor damage but not suitable for everything. See our comparison of SMART repair vs a body shop.
Want to know which repair method your damage needs? Send us a photo or book a free assessment, and we’ll explain what’s involved before any work starts.