[insert funny microwave disaster reference here]

February 7, 2008 4:09 PM

My son tried to heat up a metal pot in my ex-wife's Frigidaire microwave. Needless to say, there were sparks and pops and they turned it off right away. Now, there are some scorched-looking spots on the microwave. Is it likely or unlikely that the microwave is still in working order? Are microwaves built to handle the odd arcing incident without being destroyed?

Extra credit: Those popular single-serving soup containers have a metal ring around the top of the plastic container, yet they can be microwaved. Why these containers, but not a metal cooking pot.

posted by JimN2TAW to home & garden (6 comments total)

Microwaves are pretty hardy. It should be fine as long it really was turned off right away.
posted by Nelsormensch at 4:17 PM on February 7

Well, I don't know if they know what they're talking about, but this Yahoo! Answers post addresses your extra credit question.
posted by katillathehun at 4:20 PM on February 7

Extra credit: Those popular single-serving soup containers have a metal ring around the top of the plastic container, yet they can be microwaved. Why these containers, but not a metal cooking pot.

Density, reactivity and level of conductivity of the metal, as well as shape. Microwaves push electric charges back and forth in metal, so if the metal is too thin, it will heat up. If the metal has sharp edges or points, charges may accumulate on those sharp spots and then leap into space as a spark. If the metal ring is thick and has rounded edges, or is made of a relatively non-reactive alloy, the charges that flowed through it didn't do anything.
posted by Cool Papa Bell at 4:23 PM on February 7

Put a cup filled with water in the microwave and turn it on for 3 seconds. If you hear a loud rattle or smell smoke, you need to buy a new microwave.
posted by Kioki-Silver at 4:47 PM on February 7 [1 favorite]

When I make orange juice, I first thaw the frozen concentrate like this: remove the metal lid from the can and microwave the can (made of metal disk and cardboard cylinder) in the microwave on high for one minute. When i was taught this method, the explanation given to me was this: the disk is flat and round so there's no two points on the disk between which arcing can occur (the shortest path between two points is always through the disk, not the air). I was told also to keep it more than two inches from the wall of the microwave, and I have done so but I don't know why that is important when it's okay to be close to the floor. The metal does still block the waves, so there's a little pyramid at the bottom that stays frozen hard.
posted by winston at 7:13 PM on February 7

My microwave has a removable metal rack in the middle, so obviously just being metal is not the issue.
posted by dhartung at 11:25 PM on February 7