Car rims cleaning

13/07/2019

How to properly clean car rims and how well do the specific products on sale work?

On the market there are many detergents suitable for cleaning of the car rims and they are often praised as miraculous, but is it really so?

First of all, it is necessary to identify the type of dirt to be removed, in order to better understand the functioning of the products. Much of the dirt on the rims obviously comes from the road, i.e. dirt, dust, tar residues and asphalt debris. The most difficult polluting component to remove is to be attributed to the ferrous dust deriving from the lining of the pads. This very fine particulate sticks to the surface of the rims, insinuating itself into the most angular and hidden parts. Given the complexity of some rims, it would be optimal to use a cleaning product capable of removing dirt without manually intervening between each radius of the rim.

There are products (even quite expensive) that promise total cleaning effectiveness even without manual brushing, making only the final rinsing necessary. However, as evidenced by the numerous sites and videos on the web, we can confirm that no rims cleaner has the ability to self-clean, unless a pressure washer is used as a final wash.

Active foam

Formulation examples

The acidity of the car cleaner is not decisive (apart from a few precautions based on the material of the rims), in any case the pH must not be extreme as it could damage the rims and braking components, as well as the operator. The constant in these products are the surfactants, which are essential to remove dirt through a diffused foam that involves the entire surface of the rim. The surfactants most used for this purpose are anionics, which should act more on the particulates. The percentage of surfactants is never very high, also because oil and grease are not components of typical dirt of a rim. The surfactant serves above all as a vehicle to separate the particulate from the surface and make it easily removable by flushing water.

An important detail to consider is that, being a manual product to be sprayed, the particles and vapor that are released into the air must not be dangerous or irritating for the operator. Even the use of weak acids or bases, if used in too high percentages, can be breathed in giving an unpleasant sensation of irritation to the mucous membranes. Better to use mixtures of eco-friendly surfactants and saline fillers. The foam must have a consistency such as to create a "horizontal" jet rather than a little directional vapour, this is also possible thanks to the trigger type of the sprayer.

Some professional rim degreasers declare "active foam" on the label. They contain sodium thioglycolate, which, reacting after a few seconds with the ferrous particulate, will create the deep red ferric thioglycolate. Once the product has been applied and the color reaction has taken place, you can rinse everything off.

Even in this case, however, it is necessary to wash at high pressure or with appropriate brushing. Furthermore, the reaction with thioglycolate creates a not very pleasant acrid odor and the red wastewater is more uncomfortable to rinse and tends to stain on the ground.

Some degreasers, more common in America, contain low quantities of hydrofluoric acid which, being very reactive on metallic dirt, allows a theoretically easier cleaning. Given its toxicity, its use does not appear to be an advantage and, finally, rinsing should not end up on the ground or in the sewer.

We can define that it is not worth buying super expensive branded degreasers (some exceed 20 euros/liter), since they will have the same cleaning capacity as an economic domestic degreaser; what acts in a decisive manner on the cleaning of the rims is the mechanical action and the lance rinse.

Alkaline cleaner (not suitable for anodized rims) pH 14