Magnetized Booth

[MarcusL]

So, this is a rather strange situation. I'm not really sure which forum is belongs in, so I figured I'll just post it in lighting.

This afternoon, I was messing around with an allen wrench and I noticed that it was pulling a little bit when I put a drill bit next to it. Then I started putting it near other pieces of metal. Everything in the booth is magnetized. I tried placing the items on the floor, and even walking around the building with them(to see if it was a local magnetic field). It seems that they have become (at least temporarily) magnetized.

I have yet to try other items in the space outside of the booth, but I am rather bewildered by this situation. Has anyone ever experienced seemingly spontaneous magnetization like this before? Is there some sort of standard sound or computer equipment that could cause this? An electrical problem? There was a thunderstorm later in the afternoon, but I highly doubt some ionized air could have magnetized small pieces of metal for 8+ hours.

Any ideas are welcome. Both myself and the other tech guys are dumbfounded.

-Marcus

 

[Anvilx]

Hmm I know that I have tool magnetizer/demagnetizer. When you say the booth do you mean every bit of metal was magnetized or just the allen wrench?

 

[JD]

Two things can cause this:

1) Mechanical shock can sometimes cause metal (iron / steel) to take on a magnetic charge.
2) Very local lightning hit produces a whooper of a magnetic pulse.

Usually, stray power fields will not do this as the AC nature of power provide equal and out of phase magnetic fields which cancel each other out.

One little piece of trivia that many people do not know- Only ferrous metals (iron / steel) can take on a magnetic charge! No such thing as an aluminum magnet.

When it comes to tools however, the cause may be far less spectacular- A magnetic screwdriver (or other tool) simply bleeds its charge to fellow tools in the toolbox.

 

[CSCTech]

Not sure what could of caused this, did this suddenly start happening? I would keep your boards and computers off until it is gone however.

 

[Les]

Not sure what could of caused this, did this suddenly start happening? I would keep your boards and computers off until it is gone however.

I don't think you'd need to go that far.

I think the allen wrench is the only magnetized object in your case, other than possibly the drill bit. I believe JD's tool approach to be highly possible.

When it comes to tools however, the cause may be far less spectacular- A magnetic screwdriver (or other tool) simply bleeds its charge to fellow tools in the toolbox.

 

[ship]

I don't think you'd need to go that far.

I think the allen wrench is the only magnetized object in your case, other than possibly the drill bit. I believe JD's tool approach to be highly possible.

I'm all for the magnitized allen wrench, never magnitized my phillips screw driver but it also is slightly.

Easy test to this would be to take the allen wench outside of the booth and say to a wooden or laminate table. Still attract on the same types of fastiners or plates attracted to?

If not than you have a theory to work with, this after only crossing out the tool as a role or other things acting similar. Good scientifc method start on the other hand. Notice a phenonom, develope a theory and the next step is to test it further.

 

[MarcusL]

The filing cabinet mounted in the center of our laminate tables is also magnetized, as is a screw that was in the booth. We do have a magnetic screwdriver that is usually on the desk, but it was nowhere near the allen wrench. I didn't try attracting a non-booth object with any of the magnetized objects, will do tomorrow if the effect hasn't faded. These tools weren't in a kit or box, they were just sitting on the table (we are currently assembling a new storage cabinet). All of the objects seem to have established poles, also. Would it be possible to locate the source of the magnetism with a "compass" made from a newly magnetized object? I would think that the poles of all the objects would be lined up, assuming the same phenomenon magnetized all of them.

 

[Les]

I still think it's the allen wrench. Someone could have used the thing to take a speaker apart two months ago, and this is the phenomenon you're seeing.

And I don't think a filing cabinet (or similar) can acquire magnetic poles. Every magnet has a north and south pole, but not every magnetized object does. This is at least to my understanding.

A good test would be to take something that you know isn't magnetic (like a nail) and test it on things outside of the booth to make sure. Then take it in the booth. Does it stick to things?

This thread is interesting, but I think there's a common and logical explanation for what's going on here.

 

[church]

once something is magnetised it stays magnetised until the magnetisation decays with time (coercivity) which depends on the material and can take days to decades or you do something to remove the magnetic field, usually hetaing the magnetic item above the material Curie point or by applying mechanical shock.

Removing the magnetised tool from the booth won't remove its magnetisim unless you do something to it. If there is a large transformer nearby it will produce an alternating magnetic field which may leave a small residual magnetic field on metal we have this problem with a transformer used to convert the voltage for a scanning electron microscope (SEM) the transformer is physically 2ft*2ft*2ft and placed ten feet from the SEM but its magnetic field affects the SEM so we had to place a mu-metal (nickel-iron alloy) shield around the transfer to attenuate the magnetic field. Magnetic fields are very hard to attenuate and cannot be addressed in the same way as electric fields. This is very expensive to do.

What you are experiencing is probably a much simpler problem resulting from a magnetic item being in the room/ toolbox etc.

You can magnetise other metals i.e. AlNiCo and high performance magnets known as rare earth magnets are made from or Samarium Cobalt or Neodymium to name a few. Magnets made from iron and steel are weak and easily demagnetsied - I frequently have drill bits, screw drivers etc. become magnetised and if you drop them on the floor it removes the magnetisim. Note some screwdrivers include a magnet to hold a screw so this will not work. cordless drills have magnets in their motors - usually made from Samarium Cobalt. Note some ceramic materials also exhibit magnetic properties.

 

[shiben]

One little piece of trivia that many people do not know- Only ferrous metals (iron / steel) can take on a magnetic charge! No such thing as an aluminum magnet.
.

Not the case. If I recall correctly, there is no Iron whatsoever in the magnets in the LHC and the Tevetron. Incidentally, they also are perfectly efficient in terms of heat loss, as there is none. Part of this is due to the fact that they operate very close to absolute zero (0ºK), cooled by liquid helium. The materials on these magnets are actually current conductors, and are actually electro magnets, but still magnets none the less. Very cool things, the wires are incredibly brittle, just dropping them will break them, but they produce astounding magnetic fields. When I was taking classes at Fermilab, we got to tour the LinAc building, but couldnt see the device itself because it was running, and thus radioactive. Grounding rods everywhere, and rubber mats in front of the several hundred equipment boxes... 5'x5' cable trays packed to overflowing with tiny cables, and hundreds of fiber-optic patch bays. But I digress, My guess is that there is a powerful magnet somewhere in the room thats magnitizing all your stuff, possibly an old speaker cabinet? If you have some sort of power cable wrapped around a pipe, I think that can make an electro-magnet, but not positive about that one. Been a while since I played with this stuff. If the tools are a problem, just dropping them ought to get rid of the field, and the file cabinet could probably loose it by getting hit with a hammer a few times.

 

[JD]

If I recall correctly, there is no Iron whatsoever in the magnets in the LHC and the Tevetron.

Key words, "take on a magnetic charge." This is why iron was NOT used. They need the magnetic field to collapse when the power is removed.

As for electromagnets, anything that conducts can be used.

 

[Kelite]

The filing cabinet mounted in the center of our laminate tables is also magnetized, as is a screw that was in the booth. We do have a magnetic screwdriver that is usually on the desk, but it was nowhere near the allen wrench. I didn't try attracting a non-booth object with any of the magnetized objects, will do tomorrow if the effect hasn't faded. These tools weren't in a kit or box, they were just sitting on the table (we are currently assembling a new storage cabinet). All of the objects seem to have established poles, also. Would it be possible to locate the source of the magnetism with a "compass" made from a newly magnetized object? I would think that the poles of all the objects would be lined up, assuming the same phenomenon magnetized all of them.

 

[shiben]

As for electromagnets, anything that conducts can be used.

In general. For these in particular, it also has to superconduct.

 

[ajb]

If you have some sort of power cable wrapped around a pipe, I think that can make an electro-magnet, but not positive about that one. Been a while since I played with this stuff.

Not really. For one thing, if it's carrying AC, the magnetic field around the conductors is reversing polarity 120 times a second, so the magnetizing done in one half-cycle gets largely undone in the next--although you can certainly use AC to power electromagnets, look at any AC-coil relay or solenoid for proof of that, it's just not very effective when it comes to magnetizing an object. For another, a power cable typically includes two conductors in which equal current is flowing in opposite directions at any given time, and the two magnetic fields will largely cancel each other out. If you split the two conductors apart and wrapped them such that current was flowing in the same physical direction you could indeed produce something of an electromagnet, though. But it's not something that you can generally do accidentally as described.

 

[epimetheus]

Not really. For one thing, if it's carrying AC, the magnetic field around the conductors is reversing polarity 120 times a second, so the magnetizing done in one half-cycle gets largely undone in the next--although you can certainly use AC to power electromagnets, look at any AC-coil relay or solenoid for proof of that, it's just not very effective when it comes to magnetizing an object. For another, a power cable typically includes two conductors in which equal current is flowing in opposite directions at any given time, and the two magnetic fields will largely cancel each other out. If you split the two conductors apart and wrapped them such that current was flowing in the same physical direction you could indeed produce something of an electromagnet, though. But it's not something that you can generally do accidentally as described.

Single conductor feeder cable would be an exception here. I've seen some creatively coiled feeder cable that had definite electromagnet potential. I was taught to coil feeder cable bundles in a figure 8 just as a precaution.

Edit: It's not the force you would have to worry about with a metal object inside an AC current carry loop, but the heating due to the constantly changing magnetic flux.

 

[dcollins]

Not the case. If I recall correctly, there is no Iron whatsoever in the magnets in the LHC and the Tevetron. Incidentally, they also are perfectly efficient in terms of heat loss, as there is none. Part of this is due to the fact that they operate very close to absolute zero (0ºK), cooled by liquid helium. The materials on these magnets are actually current conductors, and are actually electro magnets, but still magnets none the less.

Are you implying that he has make an electromagnet out of his allen wrench?

Not really. For one thing, if it's carrying AC, the magnetic field around the conductors is reversing polarity 120 times a second, so the magnetizing done in one half-cycle gets largely undone in the next

It would in fact make an electromagnet - just one that cycles its poles from north to south (and varies it's strength, I believe) 60 times per second. It would also create some amount of inductance, which essentially creates a voltage proportional to the change in current. A triac dimmer set at 50% would make some exciting effects with a significant load and some inductance, though I don't care to do the math.

And I don't think a filing cabinet (or similar) can acquire magnetic poles. Every magnet has a north and south pole, but not every magnetized object does. This is at least to my understanding.

On the contrary, any magnetic material has a north pole and a south pole. This is due to the way magnetism works - allow me to attempt to explain. There are three types of materials where magnetism is concerned (five, plus electromagnetism, but some are not relevant). Diamagnetic materials are those with no unpaired electrons. These materials tend to be repelled by a magnetic field. It is a very weak effect, but it is important to note that the electrons in a material, specifically whether they are paired, is the important factor. A stronger effect than diamagnetism is paramagnetism, where there is at least one unpaired electron. When exposed to a magnetic field, these electrons will tend to align themselves with the magnetic field. The stronger the field, the stronger the effect. This is why a (paramagnetic) screw sticks to a (magnetized) screwdriver, as well as a wide variety of similar effects. The final type is ferromagnetism, which (other than electromagnetism) is the only way for a material to be magnetic on its own, in the absence of a magnetic field. It occurs for the same reasons except that the electrons will (due to quantum mechanical effects that I don't even understand myself) align themselves with one another rather than just with an external field. Ferromagnetic materials are the only ones which can retain a magnetic effect. When not magnetized, there are many small (microscopic) areas where the electrons are aligned, but the material as a whole is made up of many of these areas, and the net alignment is zero. When magnetized, all these microscopic areas are aligned and stay that way. This alignment causes a magnetic field. Because these alignments are all in the same direction, the direction the point to makes one 'pole', the opposite direction is the other 'pole'. The magnetic field lines (like when you see iron filings in a certain pattern around a magnet) go from one pole to the other. The point here is that this is all based on the fields being in the same direction, which defines the poles. A ferromagnet must therefore have poles - if it did not, then it would be a magnetic monopole, which doesn't actually exist.

 

[shiben]

Are you implying that he has make an electromagnet out of his allen wrench?

No, just pointing out that there are magnets with no iron in them.

 

[Les]

On the contrary, any magnetic material has a north pole and a south pole. This is due to the way magnetism works - allow me to attempt to explain. There are three types of materials where magnetism is concerned (five, plus electromagnetism, but some are not relevant). Diamagnetic materials are those with no unpaired electrons. These materials tend to be repelled by a magnetic field. It is a very weak effect, but it is important to note that the electrons in a material, specifically whether they are paired, is the important factor. A stronger effect than diamagnetism is paramagnetism, where there is at least one unpaired electron. When exposed to a magnetic field, these electrons will tend to align themselves with the magnetic field. The stronger the field, the stronger the effect. This is why a (paramagnetic) screw sticks to a (magnetized) screwdriver, as well as a wide variety of similar effects. The final type is ferromagnetism, which (other than electromagnetism) is the only way for a material to be magnetic on its own, in the absence of a magnetic field. It occurs for the same reasons except that the electrons will (due to quantum mechanical effects that I don't even understand myself) align themselves with one another rather than just with an external field. Ferromagnetic materials are the only ones which can retain a magnetic effect. When not magnetized, there are many small (microscopic) areas where the electrons are aligned, but the material as a whole is made up of many of these areas, and the net alignment is zero. When magnetized, all these microscopic areas are aligned and stay that way. This alignment causes a magnetic field. Because these alignments are all in the same direction, the direction the point to makes one 'pole', the opposite direction is the other 'pole'. The magnetic field lines (like when you see iron filings in a certain pattern around a magnet) go from one pole to the other. The point here is that this is all based on the fields being in the same direction, which defines the poles. A ferromagnet must therefore have poles - if it did not, then it would be a magnetic monopole, which doesn't actually exist.

Whoa -- way over my head.
I'll just smile and nod .

 

[Peyton]

No, just pointing out that there are magnets with no iron in them.

This is true, but nickel and cobalt are ferrous as well.

 

[shiben]

This is true, but nickel and cobalt are ferrous as well.

Is Niobium-tin? I was actually referring to the bending magnets used in all sorts of high energy physics, which use superconducting wire to make a magnetic field, which, if I recall right, dont even have any Iron in the casing. The point was not that its a likely candidate for the phenomena advanced by the OP, but rather an academic point as to the fact that you can indeed have a magnet that is non-ferrous, just not one that does not require a ton of energy to cool and a continuous electrical current.