DAMAGE & SAFETY GUIDE
Discovering a crack in your expensive alloy wheel is frustrating, but it doesn't always mean the wheel is destined for the scrap heap.
Discovering a crack in your expensive alloy wheel is frustrating, but it doesn’t always mean the wheel is destined for the scrap heap. Modern cast aluminium wheels are brittle; when subjected to the blunt force trauma of a pothole, they often fracture rather than bend. The critical question is whether that fracture can be safely and permanently repaired. The answer lies entirely in the location of the crack and the welding methodology used. Cosmetic ‘patch’ welding is dangerous and illegal. True structural repair requires AC/DC TIG welding, deep penetration, and rigorous thermal management.
Cracks on the inner lip/barrel (the side facing under the car) are the most common and are generally safe to weld if they are under 40mm long.
Cracks that run straight across the barrel (perpendicular to the rim edge) are ideal candidates for structural TIG welding.
UNSAFE. Cracks on the visible front face of the wheel compromise the core structural geometry and cannot be legally repaired.
UNSAFE. The spokes bear the entire rotational torque and weight of the vehicle. A cracked spoke means the wheel must be destroyed.
UNSAFE. Any stress fracturing around the central hub or the lug nut holes is catastrophic. The wheel is scrap.
If a wheel has sustained enough trauma to crack in three or more separate places, the metallurgical integrity of the entire casting is compromised.
The crack is mechanically ground out into a deep 'V' channel. This allows the weld to penetrate the full thickness of the alloy, not just sit on top.
The area is chemically purged and wire-brushed to remove all oxidisation, paint, and road salt, which would otherwise contaminate the weld pool.
We use high-frequency Alternating Current TIG welders to break the aluminium oxide layer while simultaneously fusing filler rod into the groove.
The proud weld bead is carefully prepped back to match the exact original profile of the barrel, ensuring the tyre bead seals perfectly.
Once the tyre is refitted, the wheel is leak tested to guarantee the weld is 100% airtight under pressure.
Welding an alloy wheel is an engineering intervention that must adhere to strict safety standards. Poor quality welding—such as MIG welding without proper penetration, or failing to drill the ends of the crack to stop propagation—will result in the wheel failing again, often catastrophically at high speed. Our workshop operates a zero-compromise policy. We will only execute a weld if we can guarantee it restores the wheel’s structural integrity to safe operating parameters. If your wheel falls into any of our ‘Unsafe’ categories, we will refuse the repair to protect your life and your liability.
A structural TIG weld repair typically costs between £70 and £100 per crack. This includes the V-groove preparation, welding, profiling, and pressure testing.
A properly executed, fully penetrated TIG weld is often stronger than the surrounding cast aluminium. However, if you hit another severe pothole in the exact same spot, the wheel may fracture next to the weld heat-affected zone.
Absolutely not. The heat generated by TIG welding aluminium (which melts at over 660°C) would melt the tyre rubber and potentially cause the pressurised air inside to explode. The tyre must be completely removed.
No. A professionally executed weld repair on the inner barrel of an alloy wheel is perfectly legal and will pass a UK MOT test, provided there is no distortion and the tyre seals correctly.
Don’t trust your safety to a quick cosmetic weld. Contact our engineering team for certified structural TIG welding.
