Electro Magnets

If an electro magnet is suspending something in an vacuum environment, will it act as a medium? (Will sound waves be able to pass through the magnetic field?) Thanks

Topic by Weissensteinburg   |  last reply


magnet motor or not ?

Is an angle grinder motor a permanent magnet motor or not ?,

Question by nicobotha12345   |  last reply


Neodymium Magnets? Answered

I have a motor out of an waxer/buffer and I was wondering what improvements neodymium magnets would be.  I have a couple plans for this motor, the first being for a temporary ball mill, and the second for a generator.  I am pretty sure the neodymium would be good for a generator, but what about a motor.  I am also wondering what magnets to get.  Should the north pole be the outside, south pole be the outside, should it be magnetized thru circumference, magnetized through thickness, or south on one side and north on the other.

Question by jj.inc   |  last reply


Magnets and Microwaves

I'm planning on setting up a kind of utility rack in the kitchen, and the top of the microwave is the most convenient location. I was planning on using neo magnets to hold it all in place, but does anyone have any idea if they'll affect the magnetron?

Topic by yontally   |  last reply


Magnetic spec

I was wondering how big a cylinderical grade N42 NIB magnet i would need to pull a copper weight of 20 grams from 3inches? I dont know how to calculate so... If you could, that'd be great

Topic by lifelong-newbie   |  last reply


Focusing Magnetism? Answered

Hi y'all! I am wondering if it is possible to focus magnetism? Like if you have a powerful electromagnet with a less powerful electromagnet wrapped around it. Then if both are turned on, the small one will focus the larger one creating a straight electromagnetic field and making like a "electromagnetic laser".  Thanks, joespicnictables

Question by joespicnictables   |  last reply


How can I make my son's Risk game magnetic?

I was thinking of copying the game board and gluing it to a piece of metal.  And then painting the "men" with magnetic paint, however, the paint is so pricey (especially if this doesn't work).  I was hoping to find a way to make my own magnetic paint....or perhaps a different way to accomplish this.  Any ideas?

Question by nieman565   |  last reply


Linear Magnetic Field

I am stuck in my research,please tell me a way to make a linear electromagnetic field,other than making an outer core for it please help me

Topic by ajose4   |  last reply


Convert magnetic to electrical? Answered

I am trying to find a practical way to build a device to convert magnetic energy into electrical energy, some kind of generator or other device, there are several ways in which this might work in theory but actually building the device would be more difficult to figure out.

Question by thedriftcore   |  last reply


Magnetic field redirection? Answered

Hi, I've never seen a community so welcoming and intuitive than the instructables community, so I decided this website is the best place to ask my question. I'm sure there is someone hidden deep within the fathoms of instructables that is versed in the matter of magnetic field redirection. I'm working on a project that I will post an 'ible of, (truly wireless speakers ;)) but I need some method of redirecting a magnetic field so it doesn't interfere with the speakers. I have heard of some methods, i.e. Mu metals, MagnetShield, but these are not easy to come by, especially in the UK. I have considered ordering from the manufacturer, but I am not willing to pay the exorbitant shipping costs. I would firstly like to know if such a material exists, or if alternative/better/cheaper methods are available, secondly, whether or not it can be procured in the UK, and if so, where, and thirdly, proper application of such a material. I have done lots of research into the matter, but have been left fruitless. I'm sure someone can help.                                                                 Merry Christmas,                                                                                             icyseptember

Question by icyseptember   |  last reply


what is the specification of a magnet?

What should I ask in a shop to buy a magnet(not electromagnet )?

Question by piku2323   |  last reply


Feel a magnetic force?

I was just wondering is it possible to fell a magnetic force on your skin and if so how?

Question by Dominator57   |  last reply


Will a magnet work in space? Answered

Will a magnet work in space, if so, will its strength be affected making it seem stronger or weaker?

Question by Kaptain Kool   |  last reply


Questions about Magnets

Can an electro magnet have more gauss than a neodymium of the same size?  I was just thinking about robots and advanced prosthetics. One issue with them is they require rather bulky motors to get the lifting and holding capacity we often require. So if power wasn't an issue and you could make a small elecro magnet that has more gauss/a stronger magnetic field than a neodymium magnet. Than we could make strong and smaller motors.  Just a thought. Discuss!

Topic by mpilchfamily   |  last reply


HMC5883L with external magnet

GY-273 HMC5883L Compass A. I'm waiting for my chip to arrive and will attach it to a RasPi. B.  My question is: if I align my chip to "N" then rotate a magnet round the chip - i.e. a weathervane - thoughts on how that might work? C. Can my magnet, if too strong/close, damage my chip? Thanks

Topic by liderbug   |  last reply


Magnetic Levitation Tram? Answered

Hello there instuctables, I need your help with a project i am attempting, i am in the process of making a maglev tram and i have a couple questions i need help with? 1. I have a simple circuit for a linear motor that i understand to the most part but i need help with finding an electromagnet to use / make, it needs to run on batteries and obviously the main concern here is weight and stability so the smaller the better but still needs to be strong enough to propel the tram along the track so i suppose my real question is what ammount of winding, resistance and core material would be suitable for whatever voltage i could provide! 2. Next i suppose what way round should i place the magnets, should i place many electromagnets on the rail with sensorsand permanent magnets on the tram, or should i have a powered electromagnet on the tram and permanent magnets on the track? 3. Also what hall sensor should i use to detect the magnetic fields, unipolar switches or ratiometric sensors? 4. And finally control, how would i control the motion of the tram i.e. speed and direction? Id like to thank you all in advance for any help you could provide and i hope my description is accurate enough!! many regards, Scott Photo of simple linear motor circuit (img.1) When the hall sensor (switch) senses a pole of a magnet, it activates the transistor, in turn magnetising the relay and causing the current in the electromagnet (motor) to run one direction, then as the opposite pole is detected the relay de-magnetises and reverses the current thus reversing the pole on the electromagnet! This is designed so that with permanent magnets on the track in an alternating fashion of poles (nsnsns) the tram is either pushed or pulled along the track! 

Question by Xmortx114145   |  last reply


Magnetic accelerator coil Answered

Im going to try to keep this short. So a friend and I are both sophomores at our highschool and we are both in chemistry (which is a higher level science) and i built a coilgun for last years project and attempted to build a PWM driven one this year. My friend and I want to build a rather large coilgun using either 10 microwave oven caps or close to 40 or 50 caps from computer power supplies. What i need help on is whether we should use the microwave caps which are high voltage but low capacitance or the power supply caps which are 200 volts and around 500 micro farads. I also need help on what wire to use for my coil and how many turns for the coil. i would like help with a coil for each cap size. We are planning on using either a 3millimeter by 5 centimeter long steel rod or a quarter inch bolt. our goal is to at least shoot it through the wall of the physics classroom and maybe through the door of a car. anything helps. Thank you

Question by budhaztm   |  last reply


How to make magnetic ink?

Question by Dustc53   |  last reply


Magnetic strip card reader/writer

Hey guys I am looking for a way to make a magnetic card reader/ writer. any one knows where i could find a how to for this. thanks a lot

Topic by DELETED_kclv1988   |  last reply


How to build a cheap magnetic stirrer?

I want to build a cheap magnetic stirrer. I would like it if I could get all the parts at radioshack. Not essensial though. I would also prefer using a 9 or 10 volt motor. Someone Please tell me how!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Question by sci4me   |  last reply


can i make a magnetic POV? Answered

I made a small scetch (in under 1minute) of what i mean, its really raw, just to get the idea. my idea is to make a small box, with a moving POV in it, wich moves only from the left to the right, and back. this uses a small POV system, 2 elektromagnets, some way to make the leds go in the right direction, some iron/steel, and something to controll the magnets. i wanted to know, is this possible, and if so, what magnets, controlling device do i need and how do i make the leds go in the right direction. i've considered the tracks from a CD player, but i think theres a cheaper/better way to acieve this... if i get enough info to make one, il make a full instructable of it :)

Question by godofal   |  last reply


what is the easiest way to make magnetic ink to print checks with?

Checks require "micr" ink to be read by buisness check readers. there has to be a way to make it for almost nothing

Question by norcalkracker   |  last reply


how do you know the size of the magnetic field with respect to the amount of electricity?

For example you have an electromagnet and it has an electromagnetic field how can you know how much electricity to put to make a magnetic field with a specific size (like this many volts equals this many meters in diameter)

Question by HassanA32   |  last reply


Is it possible to make the magnets lose it magnetic field permanently? Answered

I know magnets can lose its magnetic properties if exposed to heat, but is there a way to make the magnets permanently lose its magnetic fields?

Question by Plasmana   |  last reply


Can I place two speakers back to back in a box, any issues being too close or touching? Answered

2.5w 8ohm 3" speaker in a plastic box 1cm apart, possible to operate?

Question by celalboz   |  last reply


How can I do a Very Strong Electromagnetism device?

Hi, I want to do a electromagnetic device, that must be like a cilinder, because I will put a "armature" to protect that. I need 7500 Gauss, or near this. I dont know how materials is necessary and the wire, spins, turns. If I do anything wrong is possible that  device will be very hot and dangerous. This device can not be very big (can be 20cm  and diameter like a 2,3cm). Voltage is not a problem. Tks.

Question by sidjunior00   |  last reply


how can i bypass a magnetic door lock without cutting the juice ?

How can i bypass a magnetic door lock without cutting the juice ?

Question by kaerez   |  last reply


Where can i get small toroids for magnetic core memory?

I have really wanted to do this but I could never find those pesky rings!

Question by seanroberts   |  last reply


generating electricity?

Im am a novice at electics,  i think that a coil of wire through a magnetic field will generate a charge,  Yes/no?  if so would a number of coils passing through one magnetic field be more or less efficient than 1 coil passing through many magnetic feilds?

Question by QSDR   |  last reply


Magnetic Levetation? A Magnet Levitating between two Bismuth plates?

I am trying to make a magnet levitate between two bismuth plates that i made (picture 3,4,5 and 6). As you can see they are round discs about 7mm (millimeters) thick and 110 mm or 11cm (centimeters) in diameter. I bought two magnets; -the one I am trying to make levitate is 30mm (millimeters) in diameter, 10mm thick, and 22kg (kilograms) strong... -the other that is on top, the one that is pulling the magnet up is 30mm in diameter, 15mm thick and 23kg strong I put my two plates of bismuth so that there is about 25mm of space between them... Than I put in the 30mm x 10mm magnet that I want to levitate inside. The other magnet is located above the setup. I very slowly, ever so carefully start to lower the magnet. The magnet between the two bismuth plates starts to shake and at one point hits the top bismuth plate. I can't make it to levitate, either it is on the bottom plate or on the top. I tried to make the space between two bismuth plates smaller and larger, to lower the magnet by a very small amount...it didn't help... PROBLEM: I can't make it levitate, either it is on the bottom bismuth plate or on the top... WHY IS THIS? HOW CAN I FIX IT AND MAKE IT LEVITATE? Thank you for your help! -Stanislav A.K.A. Comodore

Question by comodore   |  last reply


Easiest method for magnetic levitation? Answered

I have a ring magnet of about 4 cm diameter and additional magnet pieces. for my science project, i want to suspend one magnet in the air WITH OUT ANY SUPPORT. how can i do it? what are the factors affecting the stability? can anyone tell me the simplest way to perform that? what other shapes of magnet will i need to do that?

Question by allsparkunleashed   |  last reply


Does a magnet get attracted... Answered

Does a magnet get attracted to another magnet outside of the glass of acid while the first magnet is inside the acid?

Question by Mr.Science Projects   |  last reply


Earth Magnets vs Electromagnets?? Answered

I have an earth magnet/ neodymium magnet that is pretty strong as far as pulling power is concerned but would an electro magnet have more pulling force or power. Its a small enough earth magnet that fits in my pocket. Thanks. AL.

Question by alsports2000   |  last reply


Electromagnet using permanent magnets

Hi All, I'm attempting to make a very small strong electromagnet using permanent rare earth magnets. I want to boost the magnetic field and increase the magnetic force. The magnets are 10mm in length by 5mm in radius. I have 0.4mm2 enamelled solenoid wire for the winding. My questions are, Is it possible to increase the force of a permenent  magnet? Will the induced flux into the magnet compile the force or will the EMF have to be greater to see an effect? Will paralleling two windings make the EMF stronger? As the magnets are small I have limited room to wrap windings so is there a more effective method? Any help would be great!

Topic by JimmyM5   |  last reply


Earth magnets vs Electromagnets ? Answered

If I have an earth magnet in my pocket but I want a more powerful magnet would an electromagnet be more stronger?? Thanks. AL.

Question by alsports2000   |  last reply


Drilling rare earth magnets? Answered

Is it safe to drill holes in rare earth magnets? Is the dust toxic or anything like that? I have an idea for a project but it would require drilling holes in old hard drive magnets, but if it is going to make me ill or kill me I'll find another way to do it.

Question by RadBear   |  last reply


Long range magnetic field?

Hi,right now i am stuck with my research.I want to make a long range magnetic field 14 m (approx) please help me 

Question by ajose4 


Is this the best NdFeB magnet deal?

 I'm doing a little informal research to find the best deal in neodymium magnets. The price per cubic inch seems to be extremely variable- some on the order of $10 and others in the hundreds of dollars. Can you find a better deal than I did? Conditions on the order of NdFeB magnets: * Total price, including shipping to the US,  under $30 * Contains at least four magnets with intact coating * Contains a total of at least 6 cubic inches (98322mm^3) of magnet  The best I could come up with is $4.93 per cubic inch. Can you find a better unit price?

Question by NobodyInParticular   |  last reply


Super Magnetic Senses, Achievable?

If I combined Prank's tutorial on magnetic senses with an electromagnetic coil, could a more acute sense be achieved? Also, how would one go about making it look less conspicuous than a battery and a nail duct taped to your hand? And, would one be able to sense a Ferro fluid with this sensory upgrade, or no? Thanks in advance for the answers, and I apologize if my magnetic ineptitude put a damper on your day.

Question by geckits 


need equation to repulsing magnets

I would like to know the equation for the repulsing of magnets I have a science project due and can't find the equation the internet kind of goes around the bush. If you can answer this as soon as possible  please I really hate to turn it in late. So if you have ANY helping ideas search tittle above                                                -caleb griffin-mose

Question by awe80me_k1ng   |  last reply


Shocks w/ electro magnetics

Hello Every one this is my first post, and since I am a full time student, full time para legal and full time parent, I'm just going to throw this idea out there and let others build on it. Its just an idea that I have had for years. Concerning electro magnets and shock absorber for your average car. Let me know your thoughts. My main thought is that the magnets would be working with reverse polarity add in electricity and you have a pretty good repelling force for going over those bad Jersey roads. Let me know your thoughts.

Topic by arkburn   |  last reply


Copper and magnet electricity generator

For a project in school we are designing a simple electric generator using copper wire and a magnet. The output i'm aiming for is 15V .The fixed criteria for Faraday's law as followsE =( NBA ) / T T= 3 seconds N = adjustable A = adjustable B = Neodymium 1.32 T so how do i chose my copper wire? what diameter? what kind? how do i keep the design not so BIG . How do i increase my voltage output by using a double coil system?

Question by CharithH4   |  last reply


Selectively magnetized (hemi)sphere

Hi everybody! I'm looking for a way to construct a hemisphere, - maybe 1.5" to 2" in diameter - ideally with no moving parts - where any of a number of areas on the surface could be magnetized at will I thought of having an array of tiny electromagnets starting from middle and radiating to under the surface, but frankly, that would take a long time, and I figure there would be insulation issues. Any suggestions?

Topic by drmab   |  last reply


Making a magnetically suspended puppet. Answered

Hi, I'm thinking of making a magnetically suspended puppet. The idea is to make a puppet with a neodymium magnet in its head, and suspend it under an electromagnet, using a microcontroller to control the (DC) suspension current. To regulate the current, I'll probably use a D/A converter chip controlling an op-amp current sink, though I might use low-pass filtered PWM D/A conversion. I was thinking of a way of sensing the vertical height where I put a small chunk of metal in the head as well as the magnet, modulate the suspension field slightly at a high frequency (20 kHz?), and have an extra sense coil around the suspension coil. The idea is there would be an induced current in the sense coil from the modulation. This would change as the metal chunk came nearer to the centre of the coil. The signal from the sense coil would go through a high-pass-filter (to remove any low frequency components like mains), an op-amp rectifier, and then a low-pass filter, to produce a sense voltage. I might try both para- and dia- magnetic metals (iron and aluminium) to see which works better. I'm not entirely sure whether this will work, but I'd like to try it as it seems more elegant than using a hall effect sensor. The questions I have are: - How would I go about calculating roughly what length of wire and current I'm likely to need to suspend a given weight? Just a pointer to the relevant maths should be OK - don't feel like you to have to spell it out. - Does it make any difference whether the electromagnet is long or short along its central axis? I had an idea that the field from a longer coil might extend further below the magnet than one from a shorter one, but I don't know if this is so. - Does the method I've described for sensing the height sound practical? Thanks for any help, andy (ganglion)

Question by ganglion   |  last reply


Cheap LED, Batteries and magnets

Hi, I want to make a whole bunch of lowtec-throwies, just a simple version to decorate and take pictures here, not the ultra-bright highly magnetic kind.The problem right now is that 200-300 throwies with cheap LEDs would cost more then $100 if I get the parts at our local electronic store (and that without magnets)."besthongkong" has 1000 LEDs for $10+$10S/H (=2 cents each) but does anyone know another cheap source with a larger variety and colors of low cost LEDs, maybee even low current ones? Maybee even in Europe?Second thing: Batteries. Lithium cells are rather pricey at that quantity, and cheap button cells seem to do the job.I had a couple of 1,6v LEDs on two button cells with diods I had lying arround (voltage drop). It was not very bright but they still glowed a week later.I had a cheap 12 pack assorted buttoncell blister, and I foundhttp://www.dealextreme.com/details.dx/sku.61But they seem to have even worse quality ;-) Idd probably have to use three or more and still throw some out.I remember an experiment using wire and coins, lemon juice or vinigar, which made a LED glow dimly. Any Idea how long before this DIY-Batery runs out?Third thing: Magnets!DX has 20 for less then $2. but I guess at that weight I could just magnatize some scrap metal and cut it into pieces. Thats about a third of the costs even with all the shipping :-)Anyone here that knows any other good site for LEDs, magnets and such that ship to europe?

Topic by schorhr   |  last reply



Tesla's "magnetic wave" communications idea proposed for mine safety

A report in Science Magazine describes a proposal to use Nikola Tesla's magnetic amplitude modulation as a way for trapped miners to communicate with the surface.

Topic by kelseymh   |  last reply


Magnetic Switch Paired with Timer - Help

Hi All, I am a real newbie in electronics, and have been researching. I want to build a submersible pump, using (5 gallon bucket, a toilet flush valve and a pond pump -120 volts). What I need is some way to control the pump so its not running 100% of the time. What I need is a Timer which would keep the pump running for X minutes and a magnetic switch which would activate the timer once the toilet flush valve is at a specific level.) I dont know how to set this up, I found 555 timers on amazon but not sure which ones would serve to what I need this one seems to be what i need but it is 12 volts http://www.amazon.com/Velleman-K2579-Universal-Start-Timer/dp/B000TA7A04/ref=sr_1_fkmr0_2?ie=UTF8&qid;=1420401325&sr;=8-2-fkmr0&keywords;=555+timer+10+minutes maybe this thing would work http://www.amazon.com/Packard-PTD102-Delay-Timer-Relay/dp/B004UVP90Q/ref=pd_sim_e_14?ie=UTF8&refRID;=1HAEQTK68GZRVFP7XHFZ Can someone recommend how to go about building something like that? Or maybe there is something similar already built? Thank you very much!

Topic by agitman1   |  last reply


Hacking a cassette tape adapter?

Hey everyone!  I was wondering, would it be possible to use the head in one of those cassette-to-AUX adapters as a tape reading head? Finding a new magnetic tape head is like hunting for hen's teeth, so it'd be nice if that were an option.  Many thanks!

Question by DrRorschach   |  last reply


Inrush current limiting resistor size?

I am building an application where LED strip lights will be powered off a 12V DC battery and switched on and off using a magnetic reed switch. I've been finding that the reed switch often fails to turn off when the magnet is removed. Searching on the net suggests this is because the contacts are getting fused by a large inrush current and the suggested fix is to wire a resistor in series to prevent this - so far so good but I cannot find anywhere guidance on the rating of the resistor I should use - at least guidance I can understand - as far as I can tell a resistor as low as 1 ohm may be required but not sure if I have got this correct - anyone know? Thanks

Question by SeaF1   |  last reply