Steel Spot And Plug Weld Nugget Size: Ford/Lincoln - UPDATE

Did you know that some OEMs specify nugget size for spot and plug welds? This information is typically found within vehicle-specific repair procedures or can be found under general welding guidelines. Let’s see what Ford/Lincoln has to say.

Spot Welding

Ford/Lincoln provides a Weld Nugget Chart within vehicle-specific body repair manuals in the 501-25 Body Repairs – General Information, Specifications document. This chart provides the configurations of different metal thickness to be joined and the corresponding plug weld nugget diameter. Nugget size is not based just on total metal thickness, but the layering of the metal as well. It is important to reference and follow the Weld Nugget Chart to help ensure a solid weld.

The Ford Recommended Steel Repairability Matrix specifies which types of steel can be spot or plug welded.

Per the Ford/Lincoln Workshop manuals, Welding Precautions document:

• "Factory welds may be substituted with either STRW or MIG plug welds."
• "Resistance spot welds must equal factory welds in quantity and be placed adjacent to original weld location."

Ford/Lincoln Spot Welding Requirement/Recommendation

Ford does not indicate a spot welding vs. plug welding preference in their collision repair information.

Plug Welding

Ford/Lincoln provides a Weld Nugget Chart within vehicle-specific body repair manuals in the 501-25 Body Repairs – General Information, Specifications document. This chart provides the configurations of different metal thickness to be joined and the corresponding plug weld nugget diameter. Nugget size is not based just on total metal thickness, but the layering of the metal as well. It is important to reference and follow the Weld Nugget Chart to help ensure a solid weld.

Per the Ford/Lincoln Workshop manuals, Welding Precautions document:

• "Factory spot welds may be substituted with either STRW or MIG plug welds."
• "Plug weld hole should equal 8 mm (0.31 in) diameter."
• "MAG plug welds must equal factory welds in both location and quantity."

Where the spot weld and plug weld nugget size was not identified, refer to the Steel Spot And Plug Weld Nugget Size: UPDATE article. This article provides general guidelines.

Follow OEM welding requirements, including what nugget size is required, to help ensure a complete, safe, and quality repair.

For additional Ford/Lincoln information, check out the following pages:
Ford OEM Information
Lincoln OEM Information

Additional I-CAR Collision Repair News you may find helpful:

• Back-To-Basics: Destructive Weld Testing
• Collision Information Website Access: Ford/Lincoln
• Dressing GMA Welds
• OEM Linking Pin: Ford/Lincoln Overlap Measurement With Spot Welds
• Steel Spot And Plug Weld Nugget Size: UPDATE
• Step-By-Step: Accessing Ford/Lincoln Repair Information
• Weld-Through Primer Guidelines: Ford/Lincoln
• Welding And MIG Brazing Hotspot

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