Identifying Contaminants

Identifying Contaminants

Fingerprint ID

Even though the images were magnified to make them easier to see, the contaminants they portray were visible to the naked eye as little specks or bumps on the surface or in the finish itself. Today’s finishes and clearcoats are more sophisticated than ever, and the characteristics that enhance the paint finish — the super-smooth finish, the incredible clear depth of topcoats — serve to also magnify contaminants trapped on the surface during the finishing process.

The presence of these contaminants in the finish usually requires that the finish undergo additional buffing and polishing to minimize their visibility — known as “cut-and-buff” in the shop. Once embedded, nothing short of actually stripping the finish can really remove the particles. The key is to do everything possible to make sure few particles make it to the surface finishing in progress.

Contaminants come from all quarters. Some are easier to manage, control or suppress than others. Keeping the “dirt” out of the finish in the first place through good practices and vigilance minimizes cut-and-buff, which pays off in big dollar savings.

Investigative Tools

During the investigation of suspected contaminants, it is critical to really see the nature of the contaminent. Each contaminant has its own “signature”, which helps in tracking down the source.

A microscope is a must — this is your “dirt cam”, your window into the world of the nearly-invisible. Although people tend to say, “my booth isn’t working,” what they’re really saying is “my finishes used to be great, now they’re terrible, so it must be the booth.” Our experience has shown that it is almost never “the booth”. We have instead found that practices used or not used in the shop, steps taken or not taken to prepare the vehicle, the quality of materials used, etc., were really making all the difference in the finish.

If “the booth” really is the last suspect, then one must probe the clues left behind in order to solve finish problems. There really is no other way. You have to examine the evidence with magnification. Although we show a traditional laboratory microscope and camera setup, inexpensive microscopes which send their images to a desktop or laptop computer are available today. Image quality is excellent: in fact, most of the 60x images for these pages were made using a famous-maker “toy” digital microscope plugged into an office laptop via USB. With the portability of a laptop, you can literally take the microscope to the finish problem.