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Body

Welding Precautions - Steel - Description and Operation

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Material
Item Specification
Motorcraft Premium Undercoating PM-25-A (or equivalent) —
Motorcraft Rust Inhibitor Aerosol PM-24-A (or equivalent) —





General Equipment
3 Phase Inverter Spot Welder 254-00002
Compuspot 700F Welder 190-50080
I4 Inverter Spot Welder 254-00014
Inverter Welder with MIG Welder 254-00015




Weld Nugget Chart
Test Thickness of Metal (mm) Nugget Size
0.7 + 0.7 4.3 mm (0.16 in)
0.7 + 0.7 + 0.7 4.3 mm (0.16 in)
0.9 + 0.9 4.7 mm (0.18 in)
0.9 + 0.9 + 0.9 4.7 mm (0.18 in)
1.0 + 1.0 5.2 mm (0.2 in)
1.0 + 1.0 + 1.0 5.2 mm (0.2 in)
2.0 + 2.0 7.1 mm (0.27 in)
2.0 + 2.0 + 2.0 7.1 mm (0.27 in)
3.0 + 3.0 8.7 mm (0.34 in)
3.0 + 3.0 + 3.0 8.7 mm (0.34 in)
3.0 + 0.7 4.3 mm (0.16 in)
0.7 + 3.0 + 1.0 5.2 mm (0.2 in)
2.0 + 2.0 + 0.7 4.3 mm (0.16 in)
0.9 + 0.9 + 2.0 4.7 mm (0.18 in)
2.0 + 0.9 + 1.0 5.2 mm (0.2 in)
1.0 + 3.0 + 1.0 5.2 mm (0.2 in)
3.0 + 1.0 + 2.0 7.1 mm (0.27 in)
0.9 + 0.7 + 0.9 4.3 mm (0.16 in)
General Specifications
Item Specification
Plug weld hole 8 mm (0.31 in)
Weld wire ER70S-3 or equivalent 0.9-1.1 mm (0.035-0.045 in)

WARNING: Invisible
ultraviolet and infrared rays emitted in welding can injure unprotected eyes and skin. Always use protection such as a welder's helmet with dark-colored filter lenses of the correct density. Electric welding will produce intense radiation, therefore, filter plate lenses of the deepest shade providing adequate visibility are recommended. It is strongly recommended that persons working in the weld area wear flash safety goggles. Also wear protective clothing. Failure to follow these instructions may result in serious personal injury.

The correct equipment and settings must be used when welding mild or high-strength steel. Metal Inert Gas (MIG) and Squeeze-Type Resistance Spot Welding (STRW) are the preferred methods. Surfaces must be clean and free of foreign materials.

  • Correct eye protection must be worn.
  • The correct protective clothing should always be worn.
  • Adequate ventilation must be provided to avoid accumulation of poisonous gases.
  • A test weld should always be carried out on a test sample.
  • Use cleaning brushes and abrasive grinding wheels dedicated to the type of materials being welded.
  • Follow equipment manufacturer's prescribed procedures and equipment settings for the type of welder being used. ER70S-3 or ER70S-6 wire are typically used for MIG welding steel.
  • Disconnect the battery ground cable. Refer to Section 414-01.
  • Disconnect on-vehicle modules and protect them from possible heat damage and electrical currents when welding.
  • Corrosion protection must be restored whenever bare metal repairs are made. Refer to Restoring Corrosion Protection Following Repair in this section.
  • Adequate power supply needs to be used to make sure of correct equipment performance.
  • Factory spot welds may be substituted with either STRW or MIG plug welds. Spot/plug welds should equal factory welds in both location and quantity. Do not place a new spot weld directly over an original weld location. Plug weld hole should equal 8 mm (0.31 in) diameter.
  • Vehicles equipped with optional safety canopy require removal of these components prior to any welding procedures being carried out in the roof-line or body side areas of the vehicle. Refer to Section 501-20B.

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