The procedures for replacing a portion of a damaged panel are as follows:
Determine the amount of damaged area to be removed. Using oxygas cutting and welding equipment removes the damaged area.
Once the section of the damaged panel has been removed. straighten the remaining portion to the original contour.
Place a piece of sheet metal over the area that is cut away. Mark the new sheet metal so that when you cut on the lines drawn, the piece will be slightly larger than the area being replaced.
With the new piece of sheet metal held in place by clamps, weld the sheet metal into place. Work out to the sides then down the sides. Make a continuous weld, doing a length about 6 inches long at a time. To reduce distortion, stagger the welds.
With the new sheet metal welded into place, the weld should be ground down using a disc sander. Exercise care while sanding to prevent burning or cutting holes in the sheet metal.
When replacing sheet metal, it may be necessary to shrink the sheet metal in order to achieve a professional fit and finish. Figure 8-67 shows the procedure for shrinking sheet metal. Only a small area at a time is heated and shrunk. This will cause the panel to return to its original contour when performed properly.
Before actual painting begins, it is essential that you prepare the surface for the paint by removing all traces of wax, grease, oil, and dirt. If the paint on the vehicle is of poor quality or deteriorated, remove it. In
Figure 8-67. - Metal shrinking process and sequence used for large areas.Continue Reading