Sharp Drawer Microwave Arcing Popping Noise

NOTE There are dangerous High Voltage and High Energy RF inside microwave ovens and can potential cause electric shock and death. If unfamiliar with safety procedures around these dangers, best to leave it to professionals.

These Sharp Drawer Microwave ovens have a class action settlement for electrical arcing. Mine made popping noises after about 10-15s of heating. Turns out the microwave antenna was scraping against the cover and also a arc spot above it.

Had to order a new antenna, cover plate, and microwave internal touch up paint.

Probably good to remove the outer sheet metal cover for removing antenna and cover. Cover has 4 plastic clips easily pressed out with sheet metal removed. And antenna motor can be removed to make removing antenna easier.

To remove the antenna, need a thin flat tip screw driver to wedge up the plastic locking tab and turn the plastic mount. Removing the antenna turning motor enable the antenna turn easily to get flat blade through the antenna cut out opening to wedge up the plastic locking tab and to get fingers in there to twist the mount out.

Lightly sand off burn marks, cleaned and painted with microwave touch up paint

There are likely 2 weak design points for these popular SHARP drawer microwave ovens.

The chamber for antenna is quite shallow and antenna shaft has a lot of play. Can easily make contact with cover and scrap off material. Perhaps this is the trigger for antenna eventually arcing and making contact against the top. Probably worth replacing the cover every few years depending on use level.

The oven interior paint all along the wave guide going back towards the magnetron has a rough surface. Pretty clear microwave gradually deteriorated the paint. In fact, this is what it looks like if you take the magnetron off the back (Unnecessary to change antenna + cover and I think also potentially dangerous) Looks like microwave may have eaten all the nearby paint.