Weld-Through Primer Guidelines: INFINITI

Weld-through primers are generally a zinc-based product that are applied to the mating surfaces prior to welding. Corroding zinc forms zinc oxide which protects the steel. This is called sacrificial corrosion. For a quality weld to be made it’s required that the weld-through primer be removed from the direct weld zone before welding the joint when GMA welding. Many OEMs have a position on when and how to use weld-through primer or when it shouldn’t be utilized. Let’s see what INFINITI recommends and where this information can be found.

This information, along with other part preparation guidelines, can be found in the Nissan "Body Repair Manual - Fundamentals - 2015 Edition." Per our contact at Nissan: “Use the Nissan Fundamentals Guide.” Per the Nissan Manual:

• “When spot welding panels, spot sealer must be applied to the mating surfaces to prevent rust formation.” This means to apply a weld-able seam sealer when using squeeze-type resistance spot welding (STRSW).
• “When MIG welding panels, electrify weld-through primer (metallic solution) must be applied to the mating surfaces to prevent rust formation.” This means apply a weld-through primer when using GMA welding.
• “Apply conductive anti-corrosive treatment (spot sealer for spot welding or weld-through primer [metallic solution] for GSA welding) in places that cannot be painted in the subsequent painting process.” This means to apply weld-able seam sealer for STRSW or weld-through primer for MIG, for areas that cannot be accessed for refinishing after the repairs are made. However, this does not take the place of cavity wax application after refinishing.
• “The service panel is coated with primer. Remove the primer and apply spot sealer at the portions to be welded. Do not allow the spot sealer to be forced out of the mating surface of the panel.” This means to remove the E-coat in the weld location and apply weld-able seam sealer in those areas when STRSW is used.

Use the vehicle-specific body repair manuals to determine which type of welding is required for the repair you are performing. Failure to follow OEM procedures will sacrifice the safety and quality of the repair.

For additional Nissan/INFINITI information, check out the following pages:
Nissan OEM Information
INFINITI OEM Information

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

• Step-By-Step: Accessing INFINITI Repair Information
• Weld-Through Primer Guidelines
• Welding And MIG Brazing Hotspot

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