by Bob Beranek
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Preparing for the installation is the step where many technicians make their biggest mistakes. The removal and installation steps, where skill and experience are demonstrated, are the parts every tech brags about. However, preparation is what separates the men from the boys. This is where the bonding begins and the mistakes happen.

There are three sub-sections to the preparation step: glass preparation, pinchweld preparation and preparing for the installation of the glass in the opening. Today we will deal with the first part of glass preparation, making sure the glass is free of contaminants.

Chemists tell me that improper cleaning of the glass surface is the number one reason for adhesion failure of the glass to the body of the vehicle. This can be caused by the wrong glass cleaner, the wrong wipes, the wrong handling of stubborn contaminants, or the procedure itself.

The first rule should be to use the type and brand of glass cleaner recommended by your adhesive manufacturer. Doesn’t it make sense to use products that have been tried and tested in the lab? At the very least follow their recommendations as to what criteria is important in selecting a glass cleaner.

Glass cleaners should not contain ammonia, excessive alcohols, anti-static properties, scented oils, silicones or petroleum byproducts. I have found that foaming glass cleaner is better than non-foaming because it helps find oil based contaminants by dissipation of the foam upon application. Whatever cleaner you choose should be discussed with your adhesive rep to make sure it is compatible with your urethane.

Use disposable wipes, not shop towels to wash the glass. Towels may seem more cost effective, but the result is an ineffective bond. Remember that shop towels are washed by the towel service with other towels from other customers. The other customers could be mechanics shops, oil change centers or collision centers. They are washed with harsh chemicals to clean them. Once you add a cleaning solution to the glass and wipe with a shop towel, some of these chemicals are released and applied to the bonding surface thus hindering adhesion. The best cleaning wipes are good old disposable paper towels that are used once and thrown away.

What about the stubborn tape residue or manufacturing release agent used in the encapsulation process? How do we get that off or do we have to? There are now abrasive materials available to remove these types of contaminants. I strongly suggest that you use these products and follow manufacturers’ instructions carefully to best prepare the surface for bonding.

All customers like clean and shiny windshields but don’t forget that the bonding edge is the most important part of the glass to clean, not the transparent center. We can always shine it up after the installation. The wipes are never as clean as when taken from the roll or box. This is why we clean the edges first. The procedure for cleaning the glass is as follows:

—Spray the edge with foaming glass cleaner and notice any dissipation of the foam. If there is some dissipation, scrub that areas of dissipation firmly with a clean lint-free paper towel and re-spray the area again to test.

—If there is additional dissipation or other residue present, utilize the product or procedure recommended by your adhesive manufacturer. This can include the application of an abrasive cleaner or wet scrubbing of the area or both.

—Once the edges are free from contaminants wash the remainder of the interior surface from the edges to the center.

—Make sure that the edges are perfectly dry before application of primers or preps.

Removing the old glass has always been the most difficult part of the installation process because of the physical labor required. However, the introduction of new hand tools, particularly power tools, has greatly eased this part of the installation. Remember, the goal is to get to the edge of the glass for easy cut-out. Once that is accomplished the rest is easy. To assure that the finished installation is both pleasing to the eye and safely bonded to the metal, here are some recommendations.

—Have replacement mouldings available, whether you think you will use them or not. It ensures that if even if the original mouldings were bent or misshaped, the job will always look good when finished. A good selection of universal mouldings comes in very handy to replace stretched or damaged mouldings.

—Have replacement clips as well. Even though clips are not used as often as they once were, some clips are unique. To make matter worse, many distributors do not stock a wide variety of clips because they don’t sell well and inventory turnover is low. I suggest determining the dominant car dealer in your market and obtaining the clips and retainers necessary to do those brands of vehicles. That way you will have replacements most of the time.

—Never disconnect the electrical components from the rear view mirror while the ignition is on. This could damage the vehicles’ computer or, at the very least, erase the pre-programmed memory. Either:

—Disconnect the wiring harnesses and remove the mirror and place it the back seat; or

—Remove the mirror from its pad and leave it hanging from its wiring harness.

—Pull the cowl panel. In most cases the cowl should be pulled to allow for the best bottom seal. The passenger-side airbag, in most cases, depends on the adhesion of the bottom seal of the windshield to position it properly. It also supports and solidifies the firewall. If the cowl is not pulled, the bottom seal cannot be assured and failure is a distinct possibility.

—When using hand tools for removal, start with the shortest blade in the cold knife and work up to the longer blade. This gives the technician more control of the tool and makes the cut out easier. Look for blades that have extra thinness, serration and coatings to protect the paint.

Use your body weight rather than your upper body strength to pull the cold knife. This allows you work more comfortably and reduces the chance of muscle strains or pulls.

—If you have a part with a rigid or metal-coated moulding system, use a plastic stick vertically to the pinchweld to break the moulding from the glass surface. Then force your cold knife blade between the glass edge and the broken moulding flap and under the edge of the glass. Then pull the cold knife normally. This method cuts out the glass and leaves the moulding in place which eliminates the need to pull the rigid moulding out to access the glass edge. The moulding also protects the pinchweld wall from damage from your tool.

—When using power tools, lubricate the tool by spraying water on the adhesive to be cut and on the blade itself. This reduces the harmful fumes caused by the high speed of the blades and also makes the tool work smoothly. Plain water is recommended over soapy water because it will not contaminate the bonding surface. All cut-out blades are flat on one side and beveled on the other. The flat side of the blade should be to the glass surface. The blade and the glass create a scissor-type action that eases the cut-out. The closer the cutting edge is to the power source the more torque and cutting power it has. So, use the shortest blade possible to cut the material and protect the interior trim.

The following notices from National Highway Traffic Safety Administration Office of Defects Investigation can reflect directly or indirectly on the installation of the windshield or other automotive glass parts. It is recommended that you familiarize yourself with the details, print this notice for reference and inform your customers of the recall if they have not already received notice.

•  Chevrolet Malibu 2014

Manufacturer: General Motors LLC

General Motors LLC (GM) is recalling certain model year 2014 Chevrolet Malibu vehicles manufactured June 12, 2013, through November 5, 2013. The heating, ventilation, and air conditioning (HVAC) control in these vehicles may intermittently become inoperable when the vehicle is started, preventing the windshield defroster from working. Thus, these vehicles fail to conform to the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 103, “Windshield Defrosting and Defogging Systems.”

The inability to turn on the windshield defroster may decrease the driver’s visibility thereby increasing the risk of a crash.

GM will notify owners and dealers will update the electronic climate control module software, free of charge. The recall is expected to begin December 6, 2013. Owners may contact GM at 800/521-7300. GM’s recall campaign number is 13380.

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 888/327-4236 (TTY 800/424-9153), or go to

• Toyota Avalon 2013
•  Toyota Avalon Hybrid 2013
• Toyota Camry 2013-2014
•  Toyota Camry Hybrid 2013-2014
•  Toyota Corolla 2014

Manufacturer: Toyota Motor Engineering & Manufacturing

Toyota Motor Engineering & Manufacturing North America Inc. (Toyota) is recalling certain model-year 2013-2014 Camry and Camry HV, model-year 2013 Avalon and Avalon HV and model-year 2014 Corolla vehicles. In the affected vehicles, the windshield wiper switch assembly may short circuit. As such, these vehicles fail to conform to the requirements of Federal Motor Vehicle Safety Standard, No. 104, “Windshield Wiping and Washing Systems.”

A short circuit could cause inoperative windshield wipers, reducing driver visibility and increasing the risk of a crash.

Toyota will notify owners, and dealers will replace the wiper switch assembly, free of charge. The recall began on November 8, 2013. Owners may contact Toyota at 800/331-4331.

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 888/327-4236 (TTY 800/424-9153), or go to

• Porsche 911 Carrera 2014
• Porsche Boxster 2014
• Porsche Cayman 2014

Manufacturer: Porsche Cars North America Inc.

Porsche Cars North America Inc. (Porsche) is recalling certain model year 2014 Boxster, Boxster S, Cayman, Cayman S and 911 Carrera (S, Cabriolet, S Cabriolet, 4, 4S, 4 Cabriolet, 4s Cabriolet) vehicles manufactured September 2, 2013, through September 23, 2013. In the affected vehicles, the passenger seats may be equipped with defective wiring harnesses resulting in intermittent contact with the harness plug.

The intermittent plug may cause the passenger seat frontal and knee airbags to be deactivated. In the event of a crash necessitating airbag deployment, this may increase the risk of injury to the front passenger.

Porsche will notify owners, and dealers will replace the front passenger seat free of charge. The recall is expected to begin in late November 2013. Owners may contact Porsche at 770/290-3500. Porsche’s recall number is AD04.

Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 888/327-4236 (TTY 800/424-9153), or go to