Invisible coating for parts of vintage cars wanted... and found

For vintage-car enthusiasts it isn't only the outside of the vehicle that counts. A lot of owners only want to see original parts under the hood as well. And that's not all: they need to be in working order and look like they have just come off the production line. Cebo Automotive, a company based in Ingelmunster in the Belgian province of West Flanders that repairs light-metal engine parts for vintage cars, addresses this growing demand with a unique cleaning and restoration process. To get this just right, Sirris went on the lookout for an invisible protective coating for the West Flemish company.

• Cebo looked for an invisible coating to provide restored engine parts of vintage cars with an additional protective layer.
• Sirris assessed a number of contenders and tested them extensively for their heat, dirt and chemical resistances, gloss, and hardness.
• After further analysis of the cost and practical requirements, a wafer-thin, hybrid nanocoating was chosen.

Cebo Automotive specializes in repairing cast, light-metal engine parts for vintage cars. For this the company, based in Ingelmunster in West Flanders, is relying on a cleaning and restoration process it has developed itself, making original vintage cars look good as new again.

Sirris's tests showed the best option was a wafer-thin nanocoating. In this way Cebo can protect engine components to the best possible effect without this being visible.

Discreet protection

Cebo wants to stand out from the crowd on the vintage-car restoration market with its guarantee of restored parts that look good as new for as long as possible. Therefore, the company decided to add a protective layer to the surface of the light-metal engine components. This coating needed to be not only transparent – so that the parts maintained their original appearance – but also able to withstand searing temperatures of up to 200°C. However, Cebo preferred to avoid outsourcing the work applying the coating. In other words, the cost of investing in a coating facility for this purpose should not be too high.

The acid test

Based on the technical specifications, Sirris drew up a list of possible coatings. Then in consultation with Cebo, we narrowed them down to a shortlist of five contenders. In Sirris's Smart Coating Application Lab, they were each applied to aluminum sheets which Cebo had treated using the vintage-car restoration process. The sheets were then subjected to a series of trials. In this way we assessed not only the coatings' heat and dirt resistance but also their chemical resistance, gloss, and hardness.

Wafer-thin nanocoating

Two coatings withstood the test with flying colors. In other words, they managed to both provide excellent protection for the sheets and retain their original appearance for longer. Subsequently another analysis looked at the coating costs and application and hardening methods. A silica-based hybrid coating with both organic and inorganic nanostructures turned out to be the best option. This nanocoating is so thin – at less than 10 µm – that Cebo can protect light-metal parts of vintage cars without this being visible.