Article: Lightly sand the perimeter of the area to be repaired.  Move the gun from side to side to push the plastic back into the trench. While the plastic is still soft from the soldering, lay the plastic patch over the area. Continue moving the soldering gun over the area to smooth the plastic, and fuse them together. Mix a 2 part epoxy glue, and cover the entire area of the patch. Allow to set up, sand and spray on a coat of plastic paint if desired.

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Drain the gas tank, and clean it inside and out with soapy water. Cut a plastic patch, made of a similar material to the gas tank, slightly larger than the hole to be repaired. Heat up an electric soldering gun, and drag it around the edge of the crack to create a trench. Allow to cool and dry completely.