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How to repair rust with sheet metal.
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.
For an inexpensive all purpose choice get a aws er70s 3 steel wire.
Make sure not to cut through the underlying metal.
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.
Pull the trigger of the angle grinder and run the spinning 60 grit flapper wheel over the rusted area of the metal.
Sand the area with a coarse grit sand paper using a circular motion.
Wipe the wire clean with a dry cloth.
The most permanent repair to a hole in sheet metal is to weld the hole shut.
You can then cut.
How to repair rust without welding.
Lay the removed section on a piece of fresh steel and trace the outline.
Make sure to get as much rust off the surface at this point as possible.
While sanding the rust.
The first thing to do is carefully cut away the rusted out area.
The complexity of welding increases as the thickness of the material decreases.
This should be the result with the bad part of the panel removed.
And maybe the epoxy would result in a more rustproof seam.
Attach a 60 grit flapper wheel to a 4 5 inch angle grinder and put on your safety glasses.