41 00... Straightening Steel Components

1.0 Recommended tools 

Only use those tools designed for steel repairs.

2.0 Straightening outer skin 

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

  In the case of small, soft dents (hail and parking damage), this is also possible without damaging the paintwork. This work requires a special tool and a trained employee.

• "Hot" straightening: Heat dents in their central point only with a gas flame until bright red hot. Then quench the material with a wet cloth.
• Stud welding can be used in the case of damage with accessibility only from one side (see Aftersales Assistance Portal (ASAP) - Service/Technical - Workshop equipment (Start BMW) - Shop Workshop equipment or at www.bmwgroup-wep.com). Weld on stud in the middle of the damage. The steel pin or washer is knocked out using a panel puller until the dent has been removed. The stud. pin or washer is then sanded or turned off.
• Avoid cracking.
• Avoid hardening and overstretching.
• Avoid heating and excess temperature the outer skin over large areas.
• When the surface exhibits an unevenness no greater than 2 mm after straightening steel parts, filler may be used to even out the area.

  If the unevenness is greater than 2 mm, it is necessary to carry out rounding off/tinning.

  NOTE: Only applicable within the European Union!

  European used-vehicle regulations prohibit the use of tin containing lead in motor vehicles introduced after 01.07.2003!

• For high-security vehicle, note the special information in the repair instructions!

3.0 Straightening structure 

• Repairs affecting the attachment points of assembly and chassis/suspension components must be carried out on the straightening bench with the matching set of attachments set or data sheet for the vehicle.

  Alignment brackets and data sheets are also available for the top section, e.g.: door posts, soft top mounts, cowl panel, tailgate hinges, etc.

• Check windscreen and rear window apertures for curvature by inserting the original glass.
• Take the gap dimensions for doors, engine compartment lid and tailgate from the vehicle-specific gap dimension diagram.
• Bearing body components such as e.g. engine supports, door posts, side members etc. with deformations which can no longer be returned to their original shape by "cold straightening" must be replaced.

  Heating bearing body components for better reshaping is not permitted! 

  Failure to comply with this requirement would result in a loss of original strength of up to 40 %.

• High-strength and super-high-strength steel plates as a rule cannot be reshaped. Reshaping only serves as a preparatory measure to replacing the component in order to achieve optimal joining of the connection faces.
• The body must be anchored as follows for reshaping: 

  If using vehicle-specific/universal set of attachments sets (Carbench/Celette), it is necessary to secure the body additionally with 4 retaining clamps at the spot flange of the entrance or at the 4 jacking points. The spot flange (if available) is to be preferred.

  If using universal electronic or mechanical straightening systems (Car-O-liner/Celette), it is necessary to secure the body with 4 retaining clamps at the spot flange of the entrance or at the 4 jacking points. The spot flange (if available) is to be preferred. In addition anchor at least 2 points with the securing set  .

  Failure to comply with these instructions will result in damage to the body during reshaping in non-damaged areas. Vehicle-specific alignment brackets and universal mounts may be damaged.