Mazda MX-5 Side Sill Corrosion Peculiar To NA/NB

This is a chronic disease due to being an open car. Side sill corrosion. A drain that drains water from the soft-top rain mall to the outside of the vehicle passes through the pillars and exits through the holes in the side sill. Since water remains in the gap due to the structure, it makes rot from the inside for a long time.

Peel off the painted surface and cut out the corroded part.

Treat the rusted areas inside with a rust preventive.

Weld the iron plate.

Sharpen the bulge and tap around to make a base for putty.

Apply sheet metal putty and the base is finished. Leave it for a while to harden it. After this, polish with # 80.
Move on to poly putty work.