Body Panel Removal, Repair and Replacement
This domain tests panel removal, repair and replacement: how to release a panel without damage, how to repair it safely, and how to refit it so gaps and corrosion protection are correct. The exam expects a logical sequence and awareness of structural versus cosmetic parts.
Core rules
- Before removal, disconnect the battery and observe the manufacturer's wait time for airbag systems. Support the vehicle and the panel, and mark hinge or bolt positions so alignment can be restored.
- Identify the fixing method: bolts, plastic clips, spot welds, hem flanges or adhesive. Use the correct tool: trim tools for clips, a spot-weld drill for welds, a chisel only where permitted, and a heat gun for softened adhesive within temperature limits.
- Do not cut or heat high-strength steel, boron steel or structural sections unless the manufacturer's repair method allows it. Sectioning must follow the published procedure.
- For welded replacement, clean to bare metal, apply weld-through primer at mating surfaces, make plug welds or spot welds to the specified count and spacing, and dress welds without thinning the panel.
- Replace corrosion protection after welding and grinding: zinc-rich primer, seam sealer on joints, and cavity wax inside box sections and doors.
- Check panel gaps and flushness before final paint. Adjust hinges, latches and shims rather than forcing a painted panel.
- Repair dents with hammer and dolly, stud welder or pulling equipment, then fill and finish. Do not fill over rust, tears or previous poor repairs.
Worked example
A door skin is dented beyond repair. The reasoning is: remove the door, strip the trim and glass, drill the factory welds, break the hem flange, remove the old skin, straighten the door frame, apply adhesive and weld-through primer as specified, fit the new skin, fold the hem, weld or bond, then check the door gap and operation before refinishing. Skipping the frame check means the new skin may fit badly.
Traps that cost marks
Leaving the battery connected, welding near fuel or brake lines, forgetting weld-through primer, over-grinding welds, and painting before checking gaps.