So…Our microwave is broken. Seems as if it’s been on the fritz. It got a bit dirty and started doing the sparky thing. I cleaned it and it seemed okay. Well, I decided to cook some popcorn the other day, and I left the room, and for some reason it started sparking again (again, no metal) and eventually burned a piece of that metalic/cardbord thing. I’ve read a bit about microwave repair with touch-up paint, etc., but can I get one of those cardboard things somewhere? It’s held in with one screw so I would imagine it’s designed to be replaced. The metal around the burn is also exposed, but I’ve heard that you can buy some touch-up paint for this. I’m pretty handy by the way, so I’m not afraid of repairing this.
Microwaves are the single most dangerous consumer appliances to repair. (And given that TVs and monitors with CRTs are bad, that’s saying a lot.) You can get hurt fixing them as well as injured due to a badly done fix.
I am willing to offer advice and links to someone who seems aware of what they are doing, but based on your post I am not going to do that at all.
Junk it and get a new one.
Jesus Christ!
You think I couldn’t find the information on the net myself? Get off your high-horse for a minute please. I realize they are dangerous, especially the internal components. But do you honestly think it’s so hard to sand down a spot where it was burnt and repaint it? I don’t think so. Also, all it would take would be another waveguide cover. It’s not a terribly risky thing to do, IMO.
And, “aware of what you’re doing?” I know the function of all the parts involved and why they are not working correctly. How is this unaware? Of course I know better than to screw with the stuff under the cover. But the waveguide cover isn’t really that big of a deal if you can find a replacement.
Regardless I bought a new one, since I couldn’t get the parts I need today.
That’s a sheet of compressed mica. It prevents crud from splashing onto the magnetron. Take it out to give it a good cleaning. Dry 100 grit sandpaper works pretty well for that. If its got a hole burnt thru it, scrape off the charred bits with a knife.
Check the metal housing behind the charred area for anything that could cause an arc. The holepunch used to cut the sheetmetal sometimes leaves burrs or sharp points around the edge of the hole. These act as sources for sparks. File these off, or whack them with with a hammer to move them away from the mica sheet.
Reattach the mica sheet in a new orientation.
Actually the problem was that there were sparks in the microwave for a good minute, so parts of the paint were burnt off. I needed the epoxy touch-up paint, but it is really hard to get here on short notice, so I simply bought a new one instead. The splash guard there is kinda screwed too, so I’d rather replace it. I would need to cut out a pretty big hole. It is a clever design though, the magnetron is aimed downwards, so anything splashing would have to be upwards from right next to the wall. But the real problem is the paint, actually. there is an area of a half square-inch that needs retouching.
Personally I wouldn’t waste the time or the effort on trying to fix a potentially deadly and relatively inexpensive appliance. Aside from the obvious dangers from fixing one, a microwave is one of the appliances I wouldn’t want to mess around with in terms of longer-term health safety.
Just get a new one (or professionally fixed if it’s that nice of a model).