In such an increasingly critical area such as joining and welding, adoption of the latest technology, highly developed skillsets and a thorough understanding of methodology are prerequisites. But what are the real, day-to-day challenges and opportunities encountered by body shops when it comes to this fine art?
With all car manufacturers continually striving to make their vehicles lighter and more efficient the use of aluminium in car design is becoming more and more prevalent and, eventually, aluminium will be used in practically every vehicle, meaning that there will be some aluminium repair needed in nearly every car. Body shops therefore need to ensure that they have suitable aluminium repair facilities installed to meet this inevitable growth area.
From the equipment manufacturer’s perspective, this also means continual improvements in the design of riveting equipment, spot welders and MIG/MAG welding equipment. Many of the leading car manufacturers are stipulating bonding and riveting as their recommended repair method, whether it’s for joining chassis and sill sections or for joining aluminium, steel or composite panels.
Aluminium is a very difficult material to work with and it is essential that the correct tools are used. It is important to have the correct clamping force for installing self-piercing or flow form rivets and it is generally accepted that the rivet should have at least eight tons of clamping pressure available to fit these rivets correctly, ensuring a safe repair.
As new cars enter the market there will inevitably be new types of rivets and fixings also needed. For example, where several thin panels need to be joined, the use of solid self-piercing rivets should be used. There are also countersunk flow form rivets and new designs for blind rivets. Keeping up with this fast changing repair trend is very challenging for the repairer and therefore the modular rivet tool system is proving to be their best option, whereby the repairer just adds additional tools to the system as and when required in order to keep up to date.
With the trend towards aluminium repair, bodys shops need to have a good MIG/MAG welder and a well-trained operative to use it. There are many places when joining sections where a synergic welder with a pulse arc setting must be used. The training needed to carry out this type of welding is comprehensive and demanding, but essential.
There is also a trend from car manufacturers to produce thinner steel panels, sometimes as thin as 0.5 mm. It is difficult to get good results on these thinner panels unless the welding equipment is designed to work at very low amps. To this end, welding equipment fitted with ACT (Automotive Cold Transfer) can weld as low as 32 amps, which is perfect for these thin steels. With so many different types of steel in a modern car it is essential for the repairer to have a good spot welder to ensure perfect results every time. It should have a full automatic programme to make it easy and fast for the operative, and also be water cooled to avoid overheating.
In addition, it should have a transformer gun fitted with the “C” gun design, to both avoid the dangerous electro-magnetic fields associated with cable welders and also to ensure the correct clamping force required.
Body shops face continual challenges to keep on top of changing welding repair processes and as well as the continual evolution of steel type used, vehicle manufacturers are taking an increasing interest in repair processes and the equipment employed to carry out the repair.
As an equipment manufacturer GYS has to invest in research and development resource to ensure that the equipment meets new specifications as they are set. Two recent examples where GYS was heavily involved in the process with the latest Ford spot welding and Mercedes MIG welding specifications.
Equipment that may have met manufacturer standards yesterday may not do so today. The result of this is that equipment is continually evolving and it follows that body shops have to ensure they have the latest equipment to keep ahead. Technical sales engineers demonstrate new equipment for body shops such as spot welders which are fully automatic, completely negating the need for the operator to enter any welding parameters. A lot of body shops have never seen this functionality.
Even on less complex equipment, such as dent pulling, which has been on the market for years, we are surprised by the number of repairers who are not aware of the latest functionality and thus they are getting by with very limited equipment which is reducing their efficiency. The fact that heat induction can be used to remove certain dent types is also not widely known.
There are many different repair processes and many of the premium car manufacturers are now using ‘rivet and bond’ to attach dissimilar metals such as aluminium to steel in order to eradicate contamination/corrosion. With this there is a necessity to provide equipment to carry out the reverse process in the removal of panels joined with this process. Rivet removal and heat induction equipment remains ideal.
Some manufacturers, for example GM, use a mixture of spot welding and weld through panel bond, this requires a glue setting (pre-burn) from the spot welder. Panel joining by brazing requires specialised equipment capable of operating smoothly at low amperage, sometimes as low as 15A. Welding aluminium requires good temperature and the expanded use of aluminium in vehicles is now driving a requirement for pulse MIG welders in body shops.