Metal sparks in the microwave...so why do I have a metal rack in mine?

[MichaelD]

We've all done it. Accidentally put tinfoil or a dish with a metallic rim in the nuker...and seen the resulting lightshow. :eek;

So how come my microwave has a METAL rack inside but yet I get no sparks?

 

[theNEOone]

not all metals AFAIK


=|

 

[Anubis]

do you have a Microwave-OVEN?

one that does oven things as well

 

[MichaelD]

Originally posted by: Anubis
do you have a Microwave-OVEN?

one that does oven things as well

Nope. Not a convection-cooker thing, if that's what you're thinking. Straight up nuker. Mounted above the stove.

 

[Anubis]

Originally posted by: MichaelD

Originally posted by: Anubis
do you have a Microwave-OVEN?

one that does oven things as well

Nope. Not a convection-cooker thing, if that's what you're thinking. Straight up nuker. Mounted above the stove.

yea thats what i ment


humm guess whatever metal you have doesnt react to the nuker

 

[MichaelD]

Originally posted by: Anubis

Originally posted by: MichaelD

Originally posted by: Anubis
do you have a Microwave-OVEN?

one that does oven things as well

Nope. Not a convection-cooker thing, if that's what you're thinking. Straight up nuker. Mounted above the stove.

yea thats what i ment


humm guess whatever metal you have doesnt react to the nuker

I'd like to know (very curious) what kind of metal it is. It looks like an ordinary "pie cooler" type rack. Feels like steel...doesn't bend easily, has a shiny, chromed-type finish.

 

[Eli]

Originally posted by: MichaelD

Originally posted by: Anubis

Originally posted by: MichaelD

Originally posted by: Anubis
do you have a Microwave-OVEN?

one that does oven things as well

Nope. Not a convection-cooker thing, if that's what you're thinking. Straight up nuker. Mounted above the stove.

yea thats what i ment


humm guess whatever metal you have doesnt react to the nuker

I'd like to know (very curious) what kind of metal it is. It looks like an ordinary "pie cooler" type rack. Feels like steel...doesn't bend easily, has a shiny, chromed-type finish.

It isn't because of the type of metal, I don't think. It would have the same effect on all metals.

My guess would be that's just the way its engineered. Maybe when the rack is in the microwave, it is grounded. If it's grounded, energy won't build up and you won't have sparks.

Or the rack doesen't have ANY sharp points and perhaps is also grounded. The electrons tend to jump off the metal at sharp tips or points.. and as the air around the point ionizes, current can begin to pass through the air.. and find ground.

Try it, if you dare. If the "food load" is big enough, a spoon probably won't cause any arcs.

 

[MichaelD]

Well, the rack is removable. It sits on PLASTIC hangers at the four corners...so it can't be grounded.

You had an EXCELLENT idea though...Hdn't thought of the grounding thing..you made me go look.

*shrug* I am stumped.

 

[gsaldivar]

The SHAPE of the metal determines whether or not it will arc (spark) when exposed to microwave radiation.

 

[Brutuskend]

Mine has a little metal plug in it for plugging in a temp sensor.

It's sticking right out of the side.

I've always wondered about this myself....

 

[Azraele]

I've had a microwave spark and arc with no metal inside. Needless to say I got a new one.

 

[BillGates]

Eli's right about the grounded thing - you can microwave those frozen orange juice cans that are paper with metal end covers. You just have to remove the top one and there are no issues. (do they even make those anymore?)

 

[Eli]

Originally posted by: BillGates
Eli's right about the grounded thing - you can microwave those frozen orange juice cans that are paper with metal end covers. You just have to remove the top one and there are no issues. (do they even make those anymore?)

After doing some research, gsaldivar is 100% correct, it's the shape of the metal that determines it.. and as Michael says, the rack isn't visably grounded.

The regular surface of the concentrate can end cap dissipates the electrons evenly, so no significant ionization occours and no arcs form ..

 

[Zee]

not all metal sparks. I have had chinese food in those aluminum type containers, and microwaving it for like 5 minutes was fine.

 

[imported_Rufus]

Pretty much if the metal is flat and smooth it will not spark. If it gets crinkly like aluminum foil. then it'll spark like mad

 

[erikiksaz]

Originally posted by: Rufus
Pretty much if the metal is flat and smooth it will not spark. If it gets crinkly like aluminum foil. then it'll spark like mad

But the aluminum in a cd is flat and smooth, but still sparks insanely.

 

[atom]

Originally posted by: erikiksaz

Originally posted by: Rufus
Pretty much if the metal is flat and smooth it will not spark. If it gets crinkly like aluminum foil. then it'll spark like mad

But the aluminum in a cd is flat and smooth, but still sparks insanely.

It's also very thin, which from what i've been told is part of the reason it sparks. Any thin piece of metal will tend to spark. Also a CD is not technically flat, it has many ridges in it.

 

[Eli]

Originally posted by: atom

Originally posted by: erikiksaz

Originally posted by: Rufus
Pretty much if the metal is flat and smooth it will not spark. If it gets crinkly like aluminum foil. then it'll spark like mad

But the aluminum in a cd is flat and smooth, but still sparks insanely.

It's also very thin, which from what i've been told is part of the reason it sparks. Any thin piece of metal will tend to spark. Also a CD is not technically flat, it has many ridges in it.

The extreme thin-ness is the reason it sparks. The metal doesen't have enough mass to carry really any surface charge, so as the electrons ripple across the surface, they disentigrate it because it can't dissipate the heat...

At least, that would be my analysis of it.. heh.

I also agree that it may have something to do with the ridges. If you've ever watched closely as they start forming, it's always in a pattern.. heh

 

[MAME]

so does putting a cd in a microwave and frying it damage the microwave? How about metal in general?

 

[Antisocial Virge]

That mythbusters show did a bit on this. Like someone else said, its the shape. They put a fork in without a problem but crumple up aluminum foil and lookout.

 

[Mandos]

This thread is very informative.

 

[Eli]

Originally posted by: MAME
so does putting a cd in a microwave and frying it damage the microwave? How about metal in general?

Not a cd. Other than making your microwave smell like burning plastic.

Metal in general shouldn't, but it has the potential to..

We had a microwave a while back, where we accidently put some foil in it, and the spark arced to the metal grid in the door, and it actually punched or melted a hole through the door plastic..

Whenever you cooked certain foods, a jet of steam would come out.. lol.. We just used some superglue to fill it up.

This wouldn't cause your microwave to leak microwaves, but it is "damage".

Using the microwave with nothing or very little food load is probably the hardest on it, it can overheat the magnetron since there is nothing to absorb all the energy.

 

[MAME]

so making coasters from cd's is a go? ROCK ON!

 

[ElFenix]

if you put a metal bar in the microwave it won't arc because it is easier for the electrons to go through the metal than through the air. not as much voltage potential builds up because of the conductivity of the metal. it's only when lots of potential can build in various places and not just get sent through the metal and evened out. microwaves don't scatter in the oven evenly, which is why potential can build in one place and not another.

 

[Ausm]

My guess is the rack is "plated" with microwave friendly material.


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