RepairClinic, Sears and Amazon offer microwave oven cavity paint. This paint is for use inside a microwave to repair chips and rust. Repairing these spots inside the microwave helps to prevent arcing and damage to the unit.
Microwave oven cavity paint is available as a spray and a brush-on touch-up paint. Before applying the paint, clean the microwave thoroughly to remove any grease or rust that could prevent the paint from adhering. Once the surface is clean and dry, apply one or more coats of the paint, following the manufacturer's directions.
Chips in the microwave paint are one of the common reasons owners observe sparks or electrical arcs in the device when it is in use. Use of metal or metal containing dishes in the microwave is another common cause of arcs. Sometimes these arcs strike the side of the unit and cause the paint to peel. Powerful arcs cause holes in the side of the chamber wall. If the hole is larger than the holes in the screen on the microwave door, the unit is no longer safe to use and requires replacement.
In microwave ovens with a shelf, loose support brackets sometimes cause arcing. To stop the malfunction, the owner should replace the old bracket with a new one.