4100 Straightening Aluminum Component On The Outer Skin

1.0 Prerequisites 

The component must be replaced if cracks are present.

The welding of cracks is not permitted.

2.0 Recommended tools 

• Only use tools specifically designed for aluminum repairs.
• Do not use tools and operating fluids that have already been used for steel repairs (e. g. grinding wheel). Danger of contact corrosion.
• Do not use any sharp-edged tools (notch effect).
• BMW recommends the "Alu Slimliner A (6106)" tool to repair minor and moderate body damage (Available via the applicable BMW parts catalogue).

3.0 Straightening outer skin. 

• "Cold" straightening: Press dents out from their center and smooth in an outwards direction with gentle taps.

  In the case of small, soft dents (hail and parking damage), this is also possible without damaging the paintwork. This requires special tools and suitably trained technicians.

• "Hot" straightening: Heat the component in the damaged area with a hot air blower to approx. 60°C.

  This significantly reduces the force that needs to be applied for straightening.

• Avoid notching and cracking.
• Avoid hardening and overstretching.
• Avoid heating and excess temperature the outer skin over large areas.