A wheel’s shine is not skin-deep
Choosing the right chrome wheels means easier cleaning
By Bill Campbell
Keeping wheel rims clean and polished is easier, faster and less expensive with chrome plating. All chrome wheels are shiny, but not all chrome wheels are created equally. While all chrome wheels may look alike, the challenge is to determine the quality of the plating and the entire wheel beneath.
It starts by knowing what the substrate underneath is made of. Forged aluminum is the strongest, lightest option available.
As for the finish, the look of chrome is only caused by the last stage of the plating process. It’s so thin that it contributes less than 0.3 percent of plating thickness to the original wheel. Although the chrome layer is important to the look of the wheel, the prior steps in the process are responsible for the final color and the longevity of the plated product.
The chrome plating process begins with a thorough cleaning and etching of the steel wheel, and the addition of an initial plate layer to ensure proper adhesion of the three nickel (Ni) layers to come — Semi-Bright, High-Sulfur and Bright Ni.
Here are some considerations to determine the quality of one product over another, beginning with the wheel itself.
First of all, what type of wheel did the supplier start with? Are they new and certified wheels, or previously used? Does the supplier carry only original equipment manufacturer (OEM) or only aftermarket wheels? Typically, OEMs are held to strict requirements that most likely carry over into their aftermarket business.
Is the entire wheel protected from corrosion? While the exposed side is the most visible, the inside-facing surface is subjected to the same environmental conditions. It must be painted, as there will be exposed aluminum due to contact points for the plating tooling. This coating also delays bead seat degradation and reduces tire slippage.
Another issue is whether or not the wheel is certified to a third-party quality standard and ISO 14001 environmental certification. This alone may not ensure a great product, but such compliance does ensure the company offering the product is employing quality-tested products and procedures.
Consider asking for a test report to learn the specifications, as well as what type of product testing is conducted on the plating. How often was it tested for quality control, such as adhesion, ductility and corrosion tests?
The best chrome wheel has been subjected to periodic impact testing, as well as rotary fatigue and torque retention to ensure the final product meets all requirements. Chrome plating and polishing the wheel can affect the original wheel performance.
The chrome layer should be a minimum 0.25 micrometers (um) thick and contain a minimum of 10,000 microscopic pores per sq. cm. These pores help control the corrosion process.
The three combined nickel layers should be a minimum 40 um thick. The semi-bright nickel should have sulfur content less than 0.005 percent, and the bright nickel sulfur content should be more than 0.03 percent. This is critical in delaying the onset of corrosion to the base substrate.
Tips for clean chrome wheels
Wash wheels regularly with soap and water. Never use a solution containing acid, as this can remove the chrome and attack all surfaces.
Always wash chrome with a clean rag, as foreign hard particles on the rag can scratch the finish. An off the shelf non-acidic chrome cleaner works fine on stubborn areas and restores the showroom shine.
Cleanout abrasions and pits from stone damage and seal with wax if necessary to add further protection.
These steps should result in years of enjoyment of the brightest finish in the industry.