I received an assignment from I-CAR last December to conduct the hands-on program at Marina Auto Body (Editor’s note; now owned by Chilton Auto Body) in Huntington Beach, California. I had two technicians signed up for the class, Jack Cook and Tuyen Nguyen. If you were to walk in on us, you would have thought you were at an AARP convention. Both Jack and Tu are over 60, I am over 80, and only gray hair was visible. I have known Jack for over 20 years. He’s a superior mentor and a master technician, but he has limited knowledge on aluminum panel repair. I have known Tu over 10 years, and he has no experience in aluminum panel repair. I put a dent the size of a silver dollar on the upper portion of the panel with a very large ball peen hammer.  

Three characteristics of aluminum are its high thermal conductivity, no memory, and annealing. In layman’s terms, high thermal conductivity means it will get very hot in a short amount of time and stay hot longer, too (always wear hand protection when using heat on aluminum). Aluminum has no memory, which means it will not go back to its original shape when repairing. In other words, you will physically have to bring it back to its original shape. Lastly, annealing is a permanent softening of the aluminum after it reaches a certain temperature (around 600 degrees F). Always check OEM procedures for the temperature and duration of heat allowed.  

I previously stated that aluminum has no memory, but applying heat relieves some of the pressure on the edges of the dent, allowing the metal to return to its original shape. Note that the outer edge of the dent has shrunk. The next skill that Jack and Tu had to learn was the use of a PDR push tool.  

On this part of the skill test, Jack moves the high spot (the low spot on the front side of the panel) to the low spot, pushing the dent in all directions. Look at the previous photo and notice how much of the perimeter has been reduced. 

The next skill test uses a hammer and dolly. I have some examples of the tools used in the aluminum panel repair process. 

These hammers are constructed from aluminum and have three different types of head opposite the traditional round head. 

Jack and Tu were shown how to use the hammer and dolly to move the crown of the dent to the valley using light strokes. One item that was stressed was overhammering, which causes the metal to work harden and possibly crack. The next skill was how to properly use the aluminum weld-on studs. 

Just some of the highlight pictures (from other I-CAR events). 

It is extremely important to clean the bare aluminum with a stainless steel brush (to prevent galvanic corrosion) and 99 percent alcohol (check with the OEM for what they state for cleaning) to remove all aluminum oxide. Series 6 aluminum is alloyed with silicon and magnesium. Some companies combine the two majoring elements into a single pin and in the picture below, this company has one pin with magnesium and the other with silicon.  

Both pins were attached (at 90 degrees to the panel) to a cleaned area of the panel, and the one that held better was then used to pull the dent. 

The pin was removed with a side cutter. Most technicians I have taught wanted to use a grinder with a 50 grit or coarser to remove the pin which will ruin the surface. An 80-grit DA works the best (no more than 80 grit sandpaper should be used on bare aluminum). The glue tabs were next, but I used the system when the complex dent was repaired (this part of hands-on training is scored for pass or fail). 

A block of wood and a sledgehammer was used on the body feature line to create damage on the aluminum panel. The depth was measured on the body feature line and the upper and lower sections. Next, the dent was cleaned with the alcohol, and a PDR light was used to outline the damage. At this point, we discussed the glue tab system. Both Jack and Tu had gone through the KECO theory of the system. I explained to them that it was extremely important to follow the company’s step-by-step procedures to ensure a successful glue pull (I had them photo the procedures to review when they used the system). I had them proceed to repair the complex dent with any of the tools that were available. 

Photo showing Tu utilizing KECO Glue Tab System. I failed to mention at the start of the article that our goal for the final measures was zero or metal-finished. Jack finishes up the bottom section by moving high areas to the lower area (small back vertical lines) using a special KECO PDR hammer. 

Tu’s reaction at the start of the class was to panic because he did not understand what metal-finish meant. I explained to him “No Bondo” 

Check out the smile on Tu after successfully producing a metal finished panel. Note that I wrote on his workbook “metal finish, no Bondo.”

I would like to finish with some comments on glue-tab pulling, but look at the repaired cab corner on the F-250 from the beginning of the article. 

Glue dent pull repair is going to be the primary process for panel damage repair in the collision industry. The advantages are no heat, less intrusion to factory-applied coatings, it works on both steel and aluminum, and it reduces cycle time, to name just a few. Beware of cheap systems offered by online retailers like Temu and Amazon.

Things to look for before purchasing:  

Are the tools and tabs fully guaranteed? 
Does the company offer training? 
Are the pulling devices strong enough for glue-pull dent repair? 
My final comment: You can teach us old dogs new tricks, but please be patient with us, ‘cause we’re old.