Aluminum INROADS

Sometimes lost in the discussion on new and emerging automotive materials, aluminum continues to make inroads in an ever- increasing number of parts. This month ABRN examines how aluminum is impacting the collision repair community.

Upping the aluminum ante

As of 2006, aluminum has even eclipsed steel in vehicle content as automakers applied more than 580 million pounds of aluminum sheet for closures, instrument panels, structural parts and body components, representing a 100-percent increase over the amount of aluminum used in 2002, according to Buddy Stemple, chairman of the Aluminum Association's Auto and Light Truck Group.

In August of this year General Motors announced that it will now be using aluminum wheels, blocks and cylinders to reduce vehicle weight, in concert with other improvements, to boost fuel economy and reduce the emissions in its full size SUVs and pickup trucks. "Importantly, GM used this 'lightweighting' strategy to maintain the size of its Silverado, Sierra, Tahoe and Yukon while also ensuring they continued to deliver the same towing capacity of earlier models," says Stemple.

"New research that we have provided to the National Highway Traffic Safety Administration (NHTSA) demonstrates that making hybrids and diesel cars and trucks lighter – without making them smaller – can reduce the consumers' initial vehicle cost and pay them back faster than traditional heavier-bodied models," he says.

"Due to available data and on-the-road examples of lighter, yet larger and safer vehicles, we also strongly support a size-based passenger car and light truck standard. Vehicle size, not vehicle weight, is a better safety determinant and such a size-based rule will encourage the development and availability of lower-weight materials whose use might advance fuel economy and preserve or even enhance safety," says Stemple.

"The amount of aluminum exterior panels will likely continue to grow, but the number of aluminum-intensive unitized structures will not increase as much," forecasts Jason Bartanen, technical director at I-CAR. "Some vehicle makers — Audi, Jaguar and Aston Martin, for example — have made a commitment to aluminum with some of their product offerings, but they are the minority at this point. I'd hate to speculate too much, but I believe that they will continue to be the minority when it comes to aluminum-intensive structures," he says.

Vehicles utilizing complete aluminum structures include the Audi A8, Jaguar XJ and XK series, BMW Z8, Aston Martin Vanquish, Ford GT, and the Chevrolet Corvette model Z O6. The BMW 5 and 6 series have a combination of a steel body and an aluminum front section.

Shops respond

"You have to have the equipment and you have to have the knowledge," says I-CAR instructor Toby Chess, who is eager to see more repairers become familiar with the proper methods for addressing this material. "A lot of guys don't know how to do aluminum repairs, so they throw them out and we (as an industry) wind up having to put a lot of new stuff on."

Being proficient with aluminum can help bring about a better relationship with insurers wanting to garner savings by fixing a component instead of having to fork over additional funds to pay for a new one. "It makes you look more favorable to the carrier," says Chess.

That's true, according to a body shop owner who requests anonymity. "The insurance companies come around each quarter with their reports, and we get our hands slapped for replacing rather than straightening," he says.

"Aluminum structural repairs are pretty minimal," says Car-O-Liner's Timothy W. Morgan, the company's global director of technical training. High-end vehicles aside, today's body shop should have the ability to repair "some of the small dents and dings" afflicting hoods and deck lids. "Currently they have to replace the deck lid or hood. With the proper equipment you can repair it."

One of the problem characteristics of aluminum is cracking. Depending on the specific type of material, it can be porous and crack as pulling is performed, according to Morgan. Aluminum does not have the same elasticity of steel. Sometimes low heat can be used from an induction heater to warm the area prior to moving the material a minimal amount. The adjoining areas connected can in turn be affected by the movement. Adhesives and rivet strength can be affected by the movement, he says. Individual vehicle manufacturers are best able to dictate how much, if any, pulling can be performed, he notes.

Some manufacturers require a "clean room" similar to a spray booth, while others call for curtaining to contain the area, Morgan says. "All manufacturers do agree that the tools used on aluminum must be separated from those used on steel."

Even basic hand tools, sockets and body hammers coming in contact with aluminum should not be mixed with tools used on steel. This clean room also needs plenty of ventilation to maintain air mass plus high intensity lighting as you would have in a spray area, he says.

Repair strategies can vary by OEM, ranging from adhesives, rivets and welding. "All manufacturers also agree that special equipment is required to perform these repairs. Parts placement requires universal or dedicated fixture systems on a milled bench to hold parts in place for adhesive curing or welding," Morgan says.

A critical factor with aluminum repairs is "galvanic corrosion," reports Chess, referring to the cross-contamination caused when two dissimilar metals come together. You just can't have this happening in your shop; exclusive-use tools and an isolated work area are necessities.

Some may find the concept of a clean room set aside for aluminum repairs to be a bit extreme, but Chess nonetheless stresses the importance of adequate separation of metals.

Even the tiniest shavings from a file or grinder used on steel can have a corrosive impact if it comes in contact with aluminum, he explains.

"They can find their way into pinch welds, panel seams and joints," Morgan says. "You need to be really careful about contamination. It's a really big problem. That's why it's so important to have separate tools," says Chess; an aluminum-specific tool set can be had for about $6,000. "It's designed for aluminum so you don't get the cross-contamination."

"There's quite a variety of tools and equipment out there for aluminum repairs. It's readily available," reports Ben Steinman at Ben's Auto Body in Mexico, Mo. He's not inclined to spend $6,000 for a complete kit, noting how "we've been buying pieces at a time."

Steinman is shying away from the more robust aluminum-certified OEM repair programs, saying his market has few of the higher end vehicle demographics represented by that niche. "We're in a rural area, so I don't see us doing that in the near future. The shops that I'm aware of are spending more than $100,000 to do that – I don't see many jumping on that bandwagon," he observes.

"We don't have a dedicated area to work aluminum, but we can still do it. We do quite a bit of work on ambulances, and these ambulances have aluminum bodies," Steinman continues. "The aluminum is harder to repair because of the moisture and contamination issues. We try not to mix the grinding wheels, and the moisture is something I'm really concerned about here in the Midwest with our high humidity." Once an aluminum repair is started, much effort is made to complete it quickly and avoid the ambient air because "you're not supposed to leave it exposed for too long."

Planning for your aluminum future

Steinman reports success with a newer filler product on the market. "We just recently started using that," he says.

The Wagonwork Collision Centers are manufacturer-certified for aluminum repairs to the tune of an investment exceeding $300,000, and it also serves as a training facility for this type of work, according to Anderson. He said that collision repairers who want to get into only straightening work can do so for less than $6,000.

However, he said it's important to obtain the proper education before venturing into aluminum. Wagonwork is occasionally called upon to fix the results of what other operations have "inflicted." "I've seen some repairs done by other shops that are not done properly," Anderson says.

"A lot of shops don't understand the seriousness of cross-contamination. They do not adhere to that clean environment," he says. "They've drilled holes to pull out the dent and put body filler over it, and that's not a proper repair. It causes corrosion and takes away the integrity from the panel."

Anderson advises purchasing an available system specially designed for dominating aluminum's dents and dings. "You can actually weld pins to the aluminum to pull them out," he says. "I'm not seeing a lot of shops investing in the equipment."

Additionally, Anderson said there is a distinct lack of interest in signing up for the proper training that he encourages shop owners to address. Chess and I-CAR's Bartanen are big advocates of training, and they advise repairers to take advantage of the allocated education already available.

"Many of the tools, equipment and procedures that have been used to repair aluminum over the past few years are still applicable to today's aluminum-intensive vehicles. Rivets and rivet-bonding continue to be necessary for many repairs, as well as the ability to aluminum GMA (MIG) weld. There are also weld-on dent-removal tools available for removing damage from aluminum exterior panels," Bartanen says.

I-CAR offers training in aluminum damage analysis, exterior panel repair and replacement, structural repair, and classroom and hands-on aluminum welding. A qualification test on aluminum GMA (MIG) welding also is a part of the curriculum. "The type of aluminum repairs a collision repair technician is working on will determine which I-CAR training program best suits that technician's needs," he says.

Final word: Decision time

What will be your response to aluminum repairs? An all-out effort to become certified by OEMs to repair luxury or near-luxury vehicle frames? That's an expensive proposition that few shops can afford to take. You could outsource your aluminum work to shops fully trained and equipped to handle it.

Indeed, some shops already are doing that. That direction has its own problems. You might save some money initially by delaying your investment in aluminum repair equipment. Down the road it too is an expensive proposition since you'll be saying goodbye to some much needed revenues (that could be helping pay off this investment). Your best course of action is the wide, somewhat nebulous middle road – preparing now for the kinds of aluminum work you'll see weekly or daily.

That means getting serious about training and getting your entire staff onboard – as the saying goes, much better sooner than later.