Car wheels cleaning

How to properly clean car rims and how well do the specific products that we find on sale or on specialized sites really work?

There are many specific products to clean the rims and they are often praised as miraculous, but is it really so?

Let's start by saying what are dirty and looking for our cars; obviously apart from all the dirt and soil that we collect on the street, the most difficult component to remove is the ferric dust deriving from the lining of the pads. This very fine particulate is attached to the surface of the circles by insinuating itself into the most angular and hidden parts. Therefore, given the complexity of some wheels, it would be optimal to use a detergent product capable of removing dirt by itself without acting manually, which therefore only requires the final rinse.

There are products on the market that are very similar to normal household degreasers, some very cheap, others more expensive which promise the effectiveness of the product even without manual brushing. However, as can also be seen from the numerous websites and web videos, we can confirm that most rim cleaners do not have the ability of this self-removal, unless you use a pressure washer as a final wash.

Exemples of formulation

Some manufacturers sell acid products, others alkaline, the important thing is that the pH is not extreme as it could damage the metal as well as the user. There are also neutrals, the constant in these products are the surfactants that deal with removing dirt and making foam that involves the entire surface of the rim. The most used surfactants are the anionics which theoretically act most on the particulates. The percentage of surfactants is never very high as the foam and viscosity would increase too much, moreover the oil and the grease are not typical dirt components of a rim. The surfactant therefore serves as a vehicle to separate the particulate matter 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 the vapor released in the air must not be dangerous or irritating otherwise the operator would accuse them after a few minutes. That is to say that even the use of weak acids or bases, if used in too high percentages, can be breathed giving an unpleasant sensation of irritation to the mucous membranes. Therefore, it is better to use mixtures of eco friendly surfactants and saline fillers. The foam must have a volume such as to create a "horizontal" jet rather than a poorly directional vapor. Some professional rim degreasers declare "active foam" on the label. It is understood that once the product is applied and leaving it to act for a few moments, a chemical reaction takes place between the ferric particulate present in the dirt and the sodium thioglycolate contained in these specific degreasers, this reaction creates the intense red colored ferric thioglycolate, giving signal visual to the operator to end the operation by washing. Also 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 smell and the red waste is more uncomfortable to rinse and tends to "stain" more than a traditional degreasing.
Example of "Active foam"
Example of "Active foam"