Finding Scratches

Sometimes, when installing glass in a vehicle with one (or more) previous installations, I notice that the previous tech primed some damaged areas, but missed some due to the presence of corrosion. I wonder how he missed such obvious scratches.

Of course, the scratches are obvious to me because they are now corroded and the rust expanded, making the scratches larger and more visible. In the process of installation, even the best technicians can miss small problems if they do not purposely look for them. Problems may include “flaps” of urethane, broken clips and deeper scratches that the technician thought were superficial.

As many of you know, I judge the AGSC Auto Glass Technician Olympics at Auto Glass Week. I am assisted by some of the most talented auto glass professionals in the industry, and every year I learn new things from them as well as the contestants competing.

One of the best tips I ever got was from my friend and colleague, Bruce Gates from Gates Brothers Glass in Bellefontaine, Ohio. I’ve known Bruce for more than thirty years from our days teaching the Auto Glass Technical Institute. He gave me and the other judges a tip on a way of detecting those hidden deep scratches. He took an LED pocket flashlight and went around the pinchweld. When the light hits bare metal, it makes the deep scratches light up like a neon light. If it hits the “E” coats, primer coats or other superficial scratches, it will appear dull.

The need to cover deep, bare metal scratches is imperative to the long term success of the installation and must be a top priority for every install. This is especially true today, when some adhesive companies require double priming of deep scratches for proper coverage and ultimate protection from corrosion.  However, finding all those scratches is a challenge. Here are some suggestions to make your installations corrosion free.

  1. Don’t cause scratches in the first place. Use scratch-resistant tools, such as wire tools, coated cold knife blades, and protective tapes. Use removal techniques that reduce or eliminate pinchweld damage, eliminate “plunge cuts,” use power tools as they’re designed and master hand tools for better control.
  2. Take the time to find all of the scratches. Scratches are sometimes impossible to avoid either because of vehicle design or prior sloppy installation. However, if you don’t find them all, the result is shortening the vehicle’s life and undermining the quality of the installations.
  3. Once you find the scratches, follow your adhesive manufacturers’ instructions for covering the damage. It may take special primers, special procedures or special preparation.

Corrosion is not fun to find or fix. However, corrosion is part of the job and must be fixed. Some of us live in areas of the country where corrosion may be a daily occurrence, while others see it rarely. Keep this in mind. If we don’t scratch the vehicle we are working on, or we find every scratch on the vehicle and prep it properly, there will be fewer vehicles with corrosion, and our jobs will be proportionally easier. I’m all for easier.

Bob Beranek is the president of Automotive Glass Consultants Inc.