Fiat 500 Collision Awareness Manual page 42

42 COLLISION INFORMATION
1 ­ MIG PLUG WELDS
2 ­ MIG SEAM WELD
The MIG plug welds, or "puddle welds" should be made after drilling 8 mm (5/16 in) holes and should be staggered 12.5
mm (0.5 in) apart following the centerline of the lap and should be alternating above and below the centerline 9.5 mm
(3/8 in.).
In the lap­jointed area, staggered MIG plug welds (1) are used to augment the joint and all edges of the lapped panel
seam (2) should be completely welded.
Types of Welding
STRSW (Squeeze Type Resistant Spot Welding)
• STRSW relies on the resistance of the material being welded to create heat as a current is passed through. The
materials being welded are squeezed together, and as current passes through, resistance causes heat buildup. The
force of the tips and the heat from the current allow the materials to fuse together. The current is removed and the
force from the welding tips is held during a cool down cycle. When the cool down cycle is complete, the pressure is
released and the next weld is positioned.
• Learning how to create weld coupons, refer to (Fig. 19) and then performing a destructive test using these coupons,
is the key to successfully using STRSW. Chrysler Group LLC requires a physical test using test coupons and the
methods outlined in this document to test welds prior to making repairs.
• Tip condition is very important for producing proper welds. Inspect tips often and either dress or change per equipment
manufacturer recommendations.
• High­quality welding equipment must be used or welds may be inadequate. Also, the equipment must be able to
produce repeatable welds from the beginning of the repair to the end.
GMAW (Gas Metal Arc Welding or "MIG")
Plug Weld Layout
2012 FF