How to Weld in a Patch Panel on a Car
- 1). Mark the cut line for the new patch on the side of the car panel with masking tape. Cut out the rusted or damaged metal with an air-powered cutoff wheel.
- 2). Separate the bottom pinch seam by opening it with a chisel and hammer. Set the pinch seam aside. Grind away all visible rust and rough areas of the metal surrounding the cut out area of the panel.
- 3). Cut the sheet metal to the correct size to cover the edges of the original metal by 1/2 inch on all sides. Drill holes three inches apart along all of the patch edges to make welding easier. Lay the patch in place under the original metal and reattach the pinch seam to the patch and the rest of the panels with pliers.
- 4). Place tack weld pieces along each of the holes. Put on all welding safety gear. Weld the tack pieces in place one at a time. Tap each welded piece with a body hammer while still warm to help the pieces fit together better. Allow the tack to cool for a few minutes before welding the next piece.
- 5). Grind the metal down with a 36 grit disc grinder until the original metal and the new patch sit on the same level and the patch is nearly indistinguishable from the original metal.
- 6). Fill in any uneven areas of the patch with body filler. Allow the filler to dry for 24 hours. Sand the filler smooth with the disc sander. Add more filler if necessary to make the patch invisible to the naked eye.