You can t just mask over it but have to remove it completely and replace the section with new sheet metal.
How to replace rusted sheet metal.
Remove rusted screws expect to find at least a couple of corroded screws when you work on older metal furniture and appliances and overcome these obstacles by following the screw removal.
Clean the exposed metal area with a 60 or 80 grit disc.
A rust hole compromises the structural integrity of the metal.
Then spray a rust penetrant onto the screw and leave it for about 15 minutes.
To remove rusted screws start by rapidly hitting the screw head with a hammer to break the rust seal.
Sheet metal is a huge part of any hotrod build or autobody repair.
Here is a tutorial how to video that show.
If the metal around any fastener has rusted and a hole has developed repair the rusted hole before.
A 36 grit sanding disc works best.
After slicing the patches out with a cutoff wheel next came the bending hammer and dolly session until the patches matched the holes and fit snug and flush into the flanged seat.
Whether you re fixing a dent rust hail etc.
Repairing rust or a rust hole on metal without welding requires a material that bonds and is as strong as metal.
Once down to bare metal all the damage is revealed.
This article is aimed at generally taking you through the steps of removing the old rusted metal and replacing with new 22 gauge sheet metal which is a typical gage for general body repair for smaller panels and sections.
Once the penetrant has had a chance to soak in give the screw a few more hits with your hammer to loosen the rust further and try to unscrew it.
Sand beyond the rusted area an inch or so.
How to repair rusted metal without welding.
Remove any rusted screws or screws with deteriorated washers and replace them with new ones.
You should now have a shiny solid rust free surface.
When water contacts bare metal rust forms on the surface of the metal.