Alloy wheel refurbishment: the complete guide

"Refurbishment" is doing a lot of heavy lifting as a word. It covers everything from a bloke with a rattle can on your driveway to a full strip, weld, machine and oven-cure. Both get advertised the same way and the price difference tells you almost nothing about which you are getting. So the useful question is not "how much" — it is "what are you actually going to do to my wheel?"

What a full refurbishment actually involves

Here is the sequence, in the order it has to happen. Any process that skips a step is a different job with the same name.

• Wheels off the car, tyres off the wheels. There is no shortcut here. You cannot chemically strip a wheel with a tyre on it, and you cannot inspect the inner barrel — where cracks live — until the rubber is gone.
• Chemical strip. The wheel goes into a bath that removes lacquer, colour, primer and any previous filler, back to bare aluminium. This is the step that separates a refurbishment from a respray, and it is the step most often skipped.
• Inspection. Now, and only now, you can see what you have got. Cracks, corrosion pitting, buckles, previous repairs, porous castings. Plenty of wheels look fine with paint on and tell a different story without it.
• Structural repair. Welding, straightening, machining. Structure before cosmetics, always — there is no point coating a wheel you are about to have to weld.
• Clean and key. The bare wheel is degreased and keyed to give a clean surface for the powder to grip. We do not shot-blast — the chemical strip already leaves clean, bare aluminium.
• Colour, lacquer. Two electrostatic coats, each oven-cured, typically at around 200°C. No primer coat.
• Rebuild. New valve, tyre refitted, balanced, back on the car, torqued to the manufacturer's figure.

Why powder coating rather than paint

Powder coating is not paint without the liquid — it is a genuinely different process. Dry polymer powder is given an electrostatic charge and sprayed at an earthed wheel, so it wraps around the object and clings to it evenly, including the recesses of a complicated spoke design. Then the wheel goes into an oven and the powder melts, flows out and cross-links into a single continuous skin.

The practical differences: it does not run or sag, so you get an even film thickness everywhere; it is far more resistant to chips, brake dust and salt than wet paint; and because it cures chemically rather than just drying, it is genuinely bonded. On a wheel — which lives in a bath of hot brake dust, road salt and stone strikes — that matters more than on almost any other part of a car.

Diamond cutting is not the same job

A diamond-cut wheel has a machined face rather than a painted one. The wheel is powder coated in a base colour, then mounted on a CNC lathe where a single-point diamond tool skims a few tenths of a millimetre off the raised surfaces, cutting through the base colour and leaving bright, fine-grooved aluminium behind. Then it is lacquered.

It is the finish most modern premium cars leave the factory with, it looks superb, and it comes with an honest caveat: there is bare machined aluminium sitting directly under a clear coat. Breach the lacquer — a stone, a kerb, time — and water reaches the metal and it corrodes. That is what the milky, cloudy grey look is. It is corrosion, viewed through a window, and no amount of cleaning will touch it.

It also removes material. A wheel can generally take two to four cuts across its life. After that, it is powder coat or replace. Anyone who tells you a wheel can be cut indefinitely is either not measuring or not telling you.

What a proper job costs

Ballpark UK figures, and they hold reasonably well across the country:

Typical UK ranges. Wheel size, finish and hidden damage move these — a 22in diamond-cut wheel with a cracked flange is not a £50 job, and nobody should pretend otherwise.

The number that matters more is the comparison. A single genuine replacement diamond-cut wheel for a modern German saloon routinely runs £400 to £900. A full set of four is a used-car-shaped number. Refurbishment is not the cheap option because it is worse — it is cheaper because you already own the aluminium.

How long it takes

Standard powder-coated wheels, in by 9am, in a standard colour (silver, black, white, grey, anthracite), 17in or under, with nothing hidden waiting under the old finish: usually the same day. Every one of those conditions matters, and the last one is the one that catches people — you genuinely cannot know a wheel is cracked until the finish is off it.

Diamond cutting, custom colours, larger wheels and anything needing structural repair: a day or two. If a wheel needs welding, straightening and refinishing, it is passing through three processes and an oven three times. That is not a wait-while-you-shop job.

When a wheel cannot be saved

An honest refinisher will tell you when to stop. The list is short and it is not negotiable:

• Cracks through a spoke or the hub face. Those are load paths. Nobody reputable welds them. If someone offers, walk away.
• Severe buckles, or a wheel that has been straightened repeatedly. Aluminium work-hardens. There is a point where it has had enough.
• Corrosion that has eaten through the section. Common on wheels that have lived by the coast for a decade.
• Diamond-cut wheels with no material left to cut. They can still be powder coated in a solid colour — that is often the right answer, not a consolation prize.

Questions worth asking whoever you use

• Do you chemically strip, or key and spray over the old finish? The honest answer to this tells you almost everything.
• Do you have a lathe on site, or do you send diamond-cut wheels away? Sending away means a longer wait and someone else's standards.
• Do you pressure-test welded wheels? If the answer is no, ask how they know it holds.
• How long will each finish last? Anyone promising a diamond-cut finish will last as long as powder coat is either not thinking about it or hoping you are not.
• What happens to my TPMS sensors? They are twenty years old on some cars and they snap. You want to hear a real answer.