Opening Welding Spots (Resistance Pressure Spot Welding): Procedure
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If necessary, surface-grind existing unevenness with a belt or angle grinder in the area around the welding spot.
Set punch mark in center of welding spot. Set 8 mm dia. weld spot drill bit on punch mark and drill through top panel.
NOTE:
Because the welding spots may have surface-hardened, grind them if necessary with an angle grinder and paper grinding disc.
Use a chisel to separate the sheet metal flange and remove the component.
Follow the special procedure for SPOT WELDS .