Panel bonding: are you on board?

.. Panel Bonding: Special report

The use of adhesives in the auto industry is a toAs OEMs continue to increase usage of panel and weld bonding and techniques and products become ever more sophisticated and trustworthy, so the crash repair industry must become aware of the issues involved. Bruce Gascoigne, commercial products development manager for Lord Chemical Products (Australia) says the areas of use for adhesives in the manufacture of cars overseas appears to be misunderstood, ignored or overlooked by the local repair industry. "Not only does this situation have to change, it has to change rapidly. There are many cars, including local models, where failure to use the proper performing adhesive on certain repairs will impact negatively on the safety of the repaired vehicle . . . this issue is only going to increase in importance in the future," he says.
Recently OEMs have made a concerted effort to qualify bodyshop-capable adhesives and sealants for repair of vehicles, says Gascoigne. "We have seen a considerable effort in the United States from the 'Big Three' to determine suitable adhesive and weld-bonding procedures for both recall and general accident repairs," he says. The increasing use of adhesives by OEMs must surely help to justify the position of some insurers who have insisted that 'repairing the car back to it's original condition' means only using adhesives when the OEM has done so.
Gascoigne says the stance on adhesives by OEMs means a whole new area of expertise needs to be developed within the bodyshop. Towards this end he calls for an urgent upgrade of the education programs to reflect and understand the use of adhesives and the means to repair bonded and weld-bonded components.
"I am not well-versed in the politics of the auto industry on a 'cradle to grave' basis. However, I think it is in the interests of the OEMs, insurance companies, aftermarket industry, trade groups and body repair technicians themselves to develop the rapport required to create consistent repair procedures. These must ensure the structural integrity of the vehicle is maintained in the post-repair environment. Like the move to force the use of PU adhesives for bonded windscreens in past years, it is important that adhesive technology is properly used," he says.
Leading suppliers of panel adhesives, such as Lord Chemical and 3M, claim the Australian collision repair sector is lagging behind other western nations in the use of panel bonding techniques. "The 3M panel bonding system has now been in use on cars in North America for over seven years," said Mike Howcroft, business development manager, automotive aftermarket division, 3M Asia Pacific.
In Japan, less than one year since introducing the process, 3M states it has over 3000 shops using panel bonding techniques, including most large OEM dealerships. "It is time for the insurance industry in Australia to catch up with their counterparts around the world, and provide real value to their customers, and themselves," said Howcroft.
Panel bonding is becoming an accepted process in European manufacturing according to 3M -- the new Audi aluminium models use the process on their roof panels and Jaguar uses the system on some of its rear quarter panels. General Motors and Mitsubishi in Australia both use panel bonding for the interior structure of the roof panel, however they still spot-weld the roof turrets. DaimlerChrysler states in a directive to approved repair shops in the US: "Weld-bonding [using a combination of resistance spot-welding and adhesive bonding] will provide the customer with a superior repair that will more closely mirror today's OEM process".
Lord Corporation's Fusor metal bonding products can be weld-bonded, this procedure allows for the panel to be bonded using adhesives, then spot-welded through the adhesive bond line. This particular procedure is approved by DaimlerChrysler and is a result of a joint partnership program between the car maker and Lord Corporation.
As OEM use of adhesives increases, vehicle designs are expected to allow for the use of adhesives in repairs of primary structures as well as secondary structures. Adhesives in the bodyshop will only become more important to successful tendering, cycle times and profitability. As Gascoigne puts it; "The time is approaching where the structure of the vehicle is about to make such rapid moves aided and abetted by adhesives. The only questions that remain for members of the body repair industry are: Are you in the race? Or are you still on the way to the track?"

Why use panel bonding?
According to 3M, advantages over welding include excellent corrosion protection, reduced grinding time, curing on-demand with heat, and sealing and bonding in one application. Additionally, with adhesive bonding, there's less fire danger to the technician, less danger of damaging adjacent panels, and no danger of heat warpage of sheet metal, as there can be with welding. With its easy application and short learning curve, panel bonding methods do not require the same specialized skills as welding.

Present areas of panel bonding use:

1. Closure panel hem-flange bonding.
2. Space frame assembly.
3. Frame door opening panel to reinforcements.
4. Strut tower attachment.
5. Cross floor seams on the floor pan.
6. Rear quarter panel to wheel arch.
7. Insert bonding of firewall to floor pan.
8. A, B and C pillar reinforcement around hinge mountings and striker plates.
9. Roof skin (turret) attachment.
10. Roof bow attachment.
11. Plastic closure panels (doors, decklid, liftgate, engine hood).
12. Plastic front and rear quarter panels.
13. Sunroof opening surrounds.
14. Sunroof opening panels.
15. Fixed glass bonding (windscreens, rear lights and side glass).
16. Plastic crash pad assembly.
17. Plastic and glass lamp assembly.
18. Plastic/metal grille opening panels.
19. Plastic wheel cladding.
20. Plastic rocker covers.
21. Plastic sump pan.
22. Composite springs.
23. Spoilers and plastic add-ons.
24. Radiator support panels.

Future new areas of use include:

1. Front and rear frame rails.
2. Rear beaver panel attachment.
3. Modular door frame to body roof.
4. Rocker/sill panel attachment.
5. Dissimilar metal combinations for various areas on the vehicle.

Note that in many of these areas, the adhesives will be used in combination with welding. In some cases the adhesive is used on its own.

New improved bonding
Lord Corporation has released a new and improved formulation of its popular Fusor 108B/109/B metal bonding adhesive. A spokesperson for Australian Warehouse Distributors, Australasian agents for Fusor branded products says, "The new formulation has 30 per cent more lap shear strength and it is crash-proven to exceed US Federal safety standard (FMVSS) 301."
TyIt carries a no-weld, no corrosiion lifetime guarantee as well as a weld-bodning lifetime guarantee.

Enquiries, AWD, tel: (03) 9553 1977, email: stork.awd@bigpond.com.au, website: www.fusor.com.