Make sure to get as much rust off the surface at this point as possible.
How to repair rust with sheet metal.
Lay the removed section on a piece of fresh steel and trace the outline.
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The complexity of welding increases as the thickness of the material decreases.
While sanding the rust.
If it gets dirty the weld won t turn out very strong.
Make sure not to cut through the underlying metal.
The first thing to do is carefully cut away the rusted out area.
Welding in patch panels with a flux core welder without a gas envelope is an exercise in burn through and swearing so glue it was.
Paint brush power brush the rusted areas with the wire brush on the power drill to remove the loose rust and flakes from the sheet metal.
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The first step was to cut out the rust.
How to repair rust without welding.
Sand the area with a coarse grit sand paper using a circular motion.
The welding process actually adds new steel to the thin steel and can result in a repaired spot that is stronger than the original metal.
Wipe the wire clean with a dry cloth.
The most permanent repair to a hole in sheet metal is to weld the hole shut.
Attach a 60 grit flapper wheel to a 4 5 inch angle grinder and put on your safety glasses.
This should be the result with the bad part of the panel removed.