Wheel House Alloys - Powder Coating
At Wheelhouse Alloys when we talk about alloy wheel refurbishment we are essentially referring to powder coating.
We have a bespoke powdercoat booth with two gas ovens to allow greater flexibilty and increased throughput. We use the latest powdercoat materials and have access to a wide range of colours and finishes. Powdercoating alloy wheels is a multistep process that starts with taking the wheel back to bare metal, followed by applying a powder primer or undercoat, wet painting the wheel, then applying lacquer (gloss, matt, or tinted)
The full process from start to finish requires the following stages:
- Step 1 - Remove wheels from vehicle
If you have left your vehicle with us it will be inside our secure unit and placed on axle stands or fitted with Guni wheels. Alternatively we may have spare wheels available to keep you mobile during the refurbishment process.
- Step 2 - Remove tyres, wheel weights, valves and TPMS
The tyres are removed from the wheel and marked for position and rotation. The tyres are assessed and any safety issues brought to the customers attention. We reserve the right to not refit unsafe tyres. The tyres are labelled with the unique job number and stored.
If you believe that you will need new tyres in the near future then now is an ideal time to replace them. We can quote for new tyres at this stage.
The valves and TPMS sensors are removed from the wheel. If your vehicle has TPMS (Tyre Pressure Monitoring Sensors ) we will record the TPMS position and assess the valve stem. If we can re-use the valve stem we will, but if it is single use or not fit for re-use we will fit new stems ( charges apply )
We remove all wheel weights and remove gross contamination.
- Step 3 - Clean wheel and assess
Prior to paint stripping we clean the wheels in a jet wash to remove as much brake dust and grease as possible
We also assess the wheels for bends on the balancing machine, check for cracks, and assess damage. For diamond cut wheels in particualar we try to assess whether re-cutting is possible.
At this stage we also assess paint colour if a colour match is required.
We take photos of all wheels to refer to.
- Step 4 - Paint stripping
The wheels are now placed in the Alkali Hot Strip tank for paint stripping. This process takes on average between 4-6 hours but can vary enormously depending on the age and type of paint / powder finish.
We have chosen to adopt the latest equipment and chemicals for paint stripping rather than the more traditional acid stipping technique which has a number of significant health and safety issues. Our insulated and enclosed hot strip tank heats the stripping fluid to 70 degrees whilst circulating the fluid through a filtration system. When the tank is opened, a vapour extraction system allows safe access to the wheels.
Wheels are assessed approximately every 2 hours and once fully stripped they are removed from the tank. Stripping fluid residue is then washed off the wheels in the enclosed heated jet wash cabinet.
Wheels are then left to dry .
- Step 5 - Structural repairs
Once the wheels are dry they are once again assessed for cracks - fine cracks are sometimes only visible once the paint has been stripped.
If wheels are cracked they are welded at this stage - see Alloy wheel crack welding
If wheels are bent they are straightened at this stage - see Alloy Wheel Bend Repair
- Step 6 - Shot blasting
Wheels are now shot blasted in our single wheel automatic shotblaster - AutoBlaster.
The wheel spins inside the autoblaster so that the whole wheel is shot blasted evenly to produce a surface 'key' for the powder coat to adhere to.
The length of time each wheel is shotblasted for is dependent on the condition of the wheel and type of alloy. Corroded wheels will require longer.
- Step 7 - Kerb damage and cosmetic repairs
Wheels are now prepared for powder coating.
Cosmetic damage is removed with a combination of grinders fitted with fine grinding discs and DA (Dual Action ) sanders fitted with a variety of sanding discs
We also use a variety of hand tools and files to remove or re-shape fine spoke damage.
Any areas of severe corrosion will be further sanded at this stage
Large face defects can either be spot welded or filled at this stage.
The wheel hub is then protected with a heat proof masking disc and the bolt holes plugged with bungs.
Some wheels require more intricate masking up to prevent powder coat reaching areas that must be left bare.
The wheel is then hung using a powder coat hook that attaches to the wheel via the valve hole or in some situations it is hung using wire loops.
Finally the wheel is blown off with compressed air to remove dust and debris before entering the powder coat booth
- Step 8 - Powder coating and painting
Wheels are pre heated in the oven to 220 degrees for 30 minutes in a process known as de-gassing. This removes 'gas' from the wheel that could result in air bubbles beneath the powder coat if not removed.
The powder coat is then evenly applied and the wheels placed back in the oven to cure at approximately 180 degrees for 15 minutes
Some newer powder coats come ready coloured and may now only require lacquer whereas more traditionally the powder coat acts as an undercoat / base coat on which wet paint would now be sprayed to give the finished colour. Essentially the process is dicatetd by the desired finish - paint colour and type of lacquer.
If a wheel is wet painted is is allowed to cool down slightly before paint is applied.
Once powder coated and painted it is at this stage a diamond cut wheel will be re-cut once it has cooled down
Finally the wheels are powder coat clear lacquered and placed in the oven at 165 degrees for 22 minutes to cure.
- Step 9 - Tyre fitting and balancing
Wheels are left to cool for approximately 1-2 hours whilst the curing process continues.
The wheels are then inspected for quality control and the powder coat hooks and masking discs removed.
The hubs are checked and any excess powder coat build up around the masked area sanded back.
The TPMS / Valves are refitted.
The tyres are carefully refiited, inflated to the correct pressure and the wheel balanced.
- Step 10 - Refit wheels to vehicle
The wheels are now re-fitted to the vehicles in the correct orientation.
The vehicle is lowered and the bolts / nuts tightened to the correct torque setting.
A final QC check and polish is carried out.
