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Electromagnet? Answered

Hello smart People of Instructables. I want to build a very powerful Magnet, i planned on using a microwave transformer. Heres my question: Can i plug the Transformer into my house electric? Im in Europe so we got 230V AC. And will the Magnet get stronger or weaker if i wrap really thick wire around it? Thanks for you Answers

Question by ReeVolt    |  last reply


Coil/Electromagnet

Is there any difference between a coil and electromagnet? So, is saying that a dynamic speaker has coil as correct as saying that it has an electromagnet?

Question by .Unknown.    |  last reply


Electromagnet Trouble

I'm in the development stages for my entry into the Launch It contest. Right now I'm just experimenting (or trying to) with scale electromagnets. I'm using solid core insulated copper wire from RadioShack, and a nearly fresh 9v battery. I tightly wound the wire around a finishing nail, which happened to already be magnetic, but am not getting any improvement in the magnetic field. It seems to be the same, weak size. Am I doing something wrong, or do I just need to step the size up? Thanks!

Topic by Bran    |  last reply


Help with electromagnet

I have made an attempt to make an electromagnet.I got a 10 inch iron rod with insulated copper wire wrapped around (see image)I didnt have enough wire for the whole rod, so the wire is in two seperate sectionsI tried a AA 1.5v battery, two AA 1.5v, a 9v, two 9v and a big 6v plugged in both ways (negative, positive).None seem to work.I thought it may be the two sections connected together, so i tried all the above batteries again on only one section, and it still didnt work.Can anyone help me out here ?

Topic by oxidase    |  last reply


Prewound Electromagnets

I want to make a wind turbine but I suck at coil winding. Where can I get prewound coils?

Topic by gimmelotsarobots    |  last reply


electromagnetic gun

Can anyone help me makig an electromagnetic gun, to shoot projectiles at high speed using magnetic wire, capacitor etc, from where can i get a 300 volt capacitor = not from camera =,,,,,,,,,please help guys.......

Topic by ayushdubey12    |  last reply


Electromagnet Amp

I need to build an amp circuit for an electromagnetic signal, but I don't know much about amp cicuitry. I am goin to amplify a 7800 Hz siganl from an mp3 player through a coil. I'm making one of those cart locker things. Any ideas?

Topic by gimmelotsarobots    |  last reply


Electromagnetic attraction

The site in exasperating to use. I tried to past my question but it doesn't work either, so I attached it. Please let me know. Thanks.

Topic by Bretina    |  last reply


Electromagnetism question Answered

Hi I just saw something weird, it's not an exercise or a problem but I still have a question :  Let's say we have 2 electromagnets of unequal strengths X and X+Y; between them we have a ferromagnetic bar  Let's say one has south polarity and the other one north if we change which one is stronger ex 1st is X,  2nd is X+Y than a moment after 1st is X+Y and  2nd is X the bar will have the polarity of the stronger one for a moment, right? ex for a moment the electromagnet with the south pole is stronger X + Y = the bar will become south pole than we return it to its normal strength X and make the north pole electromagnet stronger X+ Y= the bar will become north pole, right? How will such variations of the strength of the magnetic field on 1 side affect the entire device, will only the bar change its polarity and it will stop somewhere on the border of the second magnet or will the second electromagnet change it's polarity too if the first one's is very strong? (just wondering) If we fix a coil on the ferromagnetic bar will such variations in the magnetic polarities of the bar induce current in it and how much, as much as we used to produce the fields of both electromagnets or only for the field of the stronger one, or only the difference between 2? and the last question in the terms of relation between the strengths of both electromagnets (let's say in %) how much Y should be to change the polarity of the bar without affecting the polarity of the second electromagnet?  Thank you all in advance for your interest, assistance and time :)

Question by Elys    |  last reply


How to power an electromagnet? Answered

Is it better run an electromagnet of a bigger voltage(12V) with a smaller current(150mA) or with a smaller voltage 5V and a bigger current? Which will heat it up less? Does it even matter? The electromagnet will have to work for several hours so heat is my main problem. Also should I use thicker or thiner wire? I'm trying to build a electromagnet for a ferrofluid project.

Question by odvratno.zgodan    |  last reply


Help with making an electromagnet Answered

It’s not as simple as it sounds I need to make it pick up things ( screws maybe screwdriver)and I need to be able to hide it somehow under my sleeve so I can trick people in to thinking I have magical powers.

Question by zack.008    |  last reply


Control of 25 electromagnets

Hello Everyone, I'm looking for a controller to manage 25 electromagnets. I've managed to come up with a driver circuit to energise each individual electromagnet using an N channel eMOSFET in parrallel with a diode. I need a programmable controller to operate the gate of each eMOSFET but the controller must be capable of managing all 25 switches. thanks for any suggestions in advance.

Question by wameri    |  last reply


Strange Electromagnet Observation

Hey everyone. I'm fairly new to the hobby electronics world, and today I decided I'd build an electromagnet. I wound my coil around a steel bolt, and I used 3 Duracell AA (1.5V) batteries for a power supply. When I turned on the switch, I found that my beautifully wound coil took a little bit of prying to get it off of the metal base I was working on. I thought "Let's try 9 volts!" So I grabbed a Rayovac 9V battery that I had around and hooked that up in place of the 4.4V (measured) bank. The Rayovac measured to be ~9V. The electromagnet was noticeably weaker. When I tested my magnet with just one of my 1.5V batteries, it felt like it had similar strength to the 9V battery.  Can anyone explain what might be going on? Short of that, could someone tell me how to measure the current coming off of each power source?

Topic by TheMike25    |  last reply


Electromagnet battery options?

I am trying to power two dc electromagnets, the specs are: 5.5 lbs of lifting force 12vdc, 3 watts continuous duty what are my options for a battery power source?  Im having trouble figuring this out since i'm new to all of this. Any help would be great thanks!

Question by chrisack    |  last reply


Electromagnetic and Magnetic Levitation

Hi! I am setting up a levitation system and need to estimate the amount of voltage and current that is needed for a 2" dia. coil to produce 4800 Gauss. I don't have any restrictions/requirements on the core, number of turns, etc as long as it would produce 4800 Gauss with a 2" diameter. How can this be calculated? (I have spent a lot of time googling for such information, but I am pretty confused and didn't find how to calculate this) Thanks!

Topic by J50Nunlimited    |  last reply


Microwave transformer electromagnet?

Hi so I was bored and decided to make an electromagnet out of a microwave transformer by taking the secondary off and keeping the primary. I hooked it up to some 9v batteries and stuff but it wasn't that strong so I researched it a bit and found out you can hook it up to the transformer input voltage (which was 240v AC) so I did but when I turned it on it made this very loud buzzing noise and I thought I saw what looked like flame in the socket. I turned it off imediately and unplugged everything. Whatever the magnet did must of been strong because it broke itself apart slightly. I tested the sockets with a multimeter and they still say 240v but I just want to make sure I didn't do anything bad to it. Also did anything actually go wrong or was this all meant to happen?

Question by jlandreth1    |  last reply


2 Tesla Electromagnet? Answered

I need ideas for a 2 tesla electromagnet. I am trying to make the strongest magnet possible without additional cooling from a fan.. I don't know whether or not I can use high voltage, and low amps, or High amps, and low voltage. Or even inbetween.. Also, throw me that calculation for the electromagnetic strength. And if you could be awesome, explain to me how to use that formula, as I am not mathematically inclined. Thank you.

Question by Justdoofus    |  last reply


Schematics to the Electromagnetic Floater?

Could anyone please send me the circuit schematics to the electromagnetic floater?(https://www.instructables.com/id/Electromagnetic-Floater/)

Question by .Unknown.    |  last reply


Electromagnetic field generator

An electromagnetic field generator strong enough that can disturb the tv signal of your neighbour next door

Topic by SalemSnaKe    |  last reply


ElectroMagnetic Pulse Generator

Does anyone know how to make an electromagnetic pulse generator and im not talking about an EMP

Topic by cvm726    |  last reply


Electromagnetic energy and electronics

I am trying to find ideas to use electromagnetic energy in my new projects I wish u inspire me and be inspired also guys 😊

Topic by Schafiq    |  last reply


Need assistance with an electromagnet? Answered

Hi, let's say i have a permanent magnet and an electromagnet The permanent magnet is strong probably 50-100mt, the electromagnet is week less than 10mt, (the electromagnet being just a loop of wire, nothing inside, just air) I need the electromagnet to capture all the lines of the magnetic field of the permanent magnet and thus make my electromagnet  stronger, They can be placed at a distence of 3-5mm from each other I can isolate them and put them in an environement where once activated the electromagnet would offer to the permanenet magnet a path of least magnetic reluctance Since the electromagnet is weaker (and probably has less magnetic lines) will it still be able to capture all the  lines and strength of the permanent magnet and direct it with almost no losses to the other end of the electromagnet (cause the electromagnet is quite long ) How much weaker can it be untill it becomes useless in capture and directing the entire field of the PM (10 times, 100 times)? Any advice? Thank you in advance for your assistance

Question by Elys    |  last reply


Electromagnetic Floater/Levitator? Answered

Has anyone tried building this electromagnetic floater, and had it working? Because I'm trying to make it, except it doesn't work for me....I don't know whether it's the circuit, or just me. P.S; Are most of the circuits on this website reliable?

Question by .Unknown.    |  last reply


hearing electromagnetic stuff

Well, I was going to plug my ipod into some old computer speakers. my thumb touched the tip of the jack (ground) and it makes a buzzin noise. Big woop. No, as I go to reach my ipod it makes a big buzzing noise. what I was hearing was the electromagnetic waves. I reach for my cell phone and then a loud really highpitched noise ccame out. I waver my hand over my computer's power supply, I here a loud buzzing noise. How to do this: press tip of thumb to tip of 3.5mm jack turn your speakers up pretty high waver hand over complex electronics boy, do i have fun mornings, lol, being sarcastic

Topic by guyfrom7up    |  last reply


Electromagnetic induction questions.

OK, this is another one of those questions I should know, but don't.  Mainly because I have never done it before, I have a whim to build an electromagnetic launcher, something table-mounted with a range of around 3-5m (10-15 feet).  I'm not after launching nails through Coke cans. I have been browsing the web, and the designs all seem to be much more complicated than is really necessary for toy. The image below is a scan of my badly-drawn thoughts of how simple it should be. Have I got that right? I plan to use a bunch of capacitors harvested from dead electronics and connected in parallel.  Is there a recommended total capacitance for such a device? If launching a ring, must the ring slide over the ferrous core, or would there be enough umph to launch a ring balanced just past the end of the core?

Topic by Kiteman    |  last reply


Electromagnet Help! How to Make a Small but very Strong Electromagnet???

I need you help smart people of Instructables!I need to make a small Electromagnet, that uses minimum power (by that I mean the battery), but still has to be very powerful. I have a couple of questions that I need you to help me answer:Does the number of coils that is wound to the metal bar effect the strenght of the electromagnet?Does the wire gauge (20,24,28,30,34,36 wire gauge) make a difference is the strenght of the magnet?Does the voltage I supply to the coil effect the Electromagnet?What type of battery is best for an Electromagnet (AA, AAA, C, D), and what voltage (1,5V, 3V, 4,5V, 6V, 9V) ???Here is the thing, I need to make the Electromagnet super strong but taking up the minimum of energy, for example, just 1,5V. The things that are not important to me (doesn't play a factor in my device) is the number of wire winds to the metal rod and the wire gauge! So is it better to just make 1 or more (3,4,5,6...) layers of wire winds???Is it better to use thinner (36 gauge) or thicker wire (24 gauge)???Thank you a lot!Stanislav

Question by comodore    |  last reply


I want a powerfull electromagnet?

Dear friends, For my thesis, I need a strong electromagnet. How can I made it? It must be as strong as possible. Thank you so much. Best Regards. Reza

Question by mbc711    |  last reply


Building an electromagnet. Help anyone?

Hi all. I'm looking to mess with ferro fluid but I'm wondering exactly what kind of magnet I'm going to want.  From what I've looked up anything under 3000 gauss and I might as well get a rare earth magnet.  So obviously we move to electromagnets.  Basically what I'm looking for is help to create an electro magnet with these three criteria maximum gauss, minimum effort, and moderate safety.  I'd rather not have it get hot and burn myself.?

Question by djvbb12    |  last reply


Maglev Train using Electromagnets

I have made a simple maglev train, using Electromagnets. It uses repulsion. and everything is working....except Propulsion. How can I propel it? I can remake the project if required.

Topic by NHarmonia    |  last reply


How to power a strong Electromagnet?

I want to make a fairly strong electromagnet for general use but I also have a task in mind. I live in an apartment building near some students and someone egged my window. The egg dried in and now I can't reach it to clean it. I've see magnetic window cleaners before but they are cheap, weak and not up to task so I'd like to make an electromagnet to help with the scrubbing action. The windows are double glazed and the neodymium magnets I have are not strong enough. The only electromagnets I've ever made were the basic science experiment type, coiled copper around bolt with a battery to power. For this I assume I'll need a large battery or would it be mains powered? Any suggestions?

Question by nodnodwinkwink    |  last reply


Electromagnetic pulse generator plans?

Does anybody know where I can find plans for an electromagnetic pulse generator?

Topic by abun1991    |  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


How to measure electromagnet by Tesla?

I will be doing an experiment how powerful the magnetic field of an electromagnet, and my guess is the more you twist the wire the more power it generate. But i don't know how to measure the magnetic field by using the unit Tesla.

Question by defineSCIENCE    |  last reply


Homemade Electromagnetic Drill Stand

Hi every body In this video I make an electromagnetic drill standFor this project I’m using two microwave transformers one psu 350 watt from old pc, epoxy resin. Aluminium swarfs, some pieces from steel and one piece of bronse. I hope you enjoy the video !https://www.youtube.com/watch?time_continue=123&v;=J9I3FJ8dROk&feature;=emb_logo

Topic by versam    |  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

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


Layers V.S. Length; Electromagnets ? Answered

Ok, so I am going to be working on a project that involves electromagnets and the on thing I have never gotten straight is this: To make the most effective magnetic field possible do I make the (hypothetically) 100' of wire a long coil with only a couple of layers or 100' of wire a short coil with many layers? I have always come across conflicting views on if length improve the fields or weaken them. Any insight would be helpful and if you could also provide a good reference site for these types of questions that would also be appreciated. 

Question by Jayccob    |  last reply


electromagnetic pinch effect demonstrator

Greetings, Instructors! I've done some searching in the Technology section already, but (as you know) it's huge, and I didn't see anything that was close enough to what I'm looking for except the electromagnetic coil gun. I want to replicate a demonstrator I saw, once upon a year, at the Smithsonian Institution. A thin-walled metal tube was dropped into the spaces inside two stacked, separated coils, as if it were an axle for a pair of wheels. A brief, large current was then run through the coils; the induced currents in the tube produced the "theta pinch" effect, crushing the regions of the tube that were within the coils. (The machine was set up to sell the products for a token price; the impressively crushed tube was dispensed as a souvenir.) I need advice on the type and capacity of capacitor, thyristor, power supply, etc. to employ. Has anyone here built one, or know someone who has? Thanks!

Question by Argent47    |  last reply


electromagnets to push objects without touching it

Hi, i want to make an electromagnetic coil which can push another metal plate without touching it from destance of approx. 50cm . max voltage allowed is 24 v.please suggest me way of getting electromagnet strong enough to push weight of approx 7kg without touching it.can you also suggest me material that can easily repel electromagnet?please help asap.

Question by KiranS13    |  last reply


I need to make an electromagnet that continues to turn on and off (on 20 seconds off 45 seconds)

Hello, I am trying to make an electromagnet that turns on and off on an interval. On for 20 seconds off for 45 second. It would continue to turn on and off until the power is turned off. Any and all suggestions as to how to make (or buy) this would be great! I am making this for an art piece.. I am a glass artist so I am not well versed in any of this electrical engineering Thanks! Maia

Topic by MaiaS5    |  last reply


HELP!! i am building an using the magnet on the back of a car speaker.

I am also going to try to channel the electromagnetic waves. where should i start? How much energy would i need? How can i contain the magnetic field? at what point does the energy become harmful to the human body?

Question by tprusak    |  last reply


what will be the wire size ?if i would like to make a eletro magnet ?which length could be 1200 mm and core width 40mm?

Dear friends, I want to make a drum with magnetic bars, to capture max matal particals from amixture, size of magnet should be 1200mm*---- ,suggest me what would be the Diameter of wire Regards Nadeem

Question by nadeem Ashraf    |  last reply


Optical Image Stabilization

Hi everyone, I have a little awkward question here but I am sure someone who knows a little bit more about electronics can give me good advice. I took apart the lens from a consumer video camera and took out the Optical Image Stabilization module in an effort to figure out how it works and possibly hijack the signal so I can control the movement. In the camera this module is getting the signal from the accelerometer so it knows how to engage the two electromagnets and counteract the movement (shaking). What I have done is take the leads that go into it and try to fake what gyro sends to this element. So far I have noticed that when I short 1 and 2 or 3 and 4 the element goes to one side or up. So I put a potentiometer on it (2K ohm) and it gives me some control by turning the dial, but not good enough. Has anyone any idea how can I achieve a gradual movement of this lens element vertically and sideways with a slider or dial of some sort? Your help would be greatly appreciated!

Topic by Sudija  


Wireless circuit diagram needed for an Electromagnet.

Hey guys, i urgently need to build a wireless circuit using a simple on/off electromagnetic circuit that would drop a metal object when the circuit is switched off. i have a 12V dc powered electromagnet as well as RF receiver and transmitter pair. the receiver needs to be fitted with the electromagnet and i would be using 4.5v dc power supply for the receiver using 3x1.5V button cells. Kindly help me with circuit diagrams and/or a list of other components such as generic IC/ timer 555/ resistors, capacitors, etc. which would be needed for me to build the circuit. Thanks a lot.

Question by him1703    |  last reply


Building a strong electromagnet, need advice Answered

Hi trying to understand how to build an electromagnet It must be 38-40 kg strong, and powered by 1,5-3v rechargeable batteries (operating for at least few years) and using as few amp as possible, it will be switched on and off 1-2 times per sec I know that it's possible cause it exists already; http://www.grainger.com/product/2KFP1?gclid=CjwKEAiAxNilBRD88r2azcqB2zsSJABy2B96VIJ19MORYbL2E3XKvdOrg6bK6_U-Ko7P7ZAGq3_UqRoC5Kvw_wcB&cm;_mmc=PPC:GOOGLEPLAA-_-Security-_-Locking%20Systems-_-2KFP1&ef;_id=VLan-gAAACg-Rw6I:20150114173308:s Mine just needs to be a little stronger and work 24/7 I would be thankful if you could propose any other source of constant energy (to replace the batteries) or a solution to make them last longer

Question by Maxc13    |  last reply


Simple nail and wire Electromagnet problem ! Answered

So I built a simple electromagnet out of a nail and wire, I hooked it up top power and a switch. What I need to do is to lift a small metal ball the size of a common marble with my electromagnet, when I press the switch ( momentary, when you press it, it shut off power and when you release it power get back) the ball should fall of it, but problem is, the ball stay magnetized to the nail !! The only solution I found up to now is to make the electromagnet just enough powerfull to hardly lift the ball, but I hate it because its a pain to get the ball to stick on and it often fall off randomly. Is there a way the ball could fall off every time I press the switch without reducing the strength of my electromagnet? Thank you !!

Question by Patented    |  last reply


EMF [electromagnetic field] shield fabric?

Does anyone know how to make EMF [electromagnetic field] shield fabric?

Question by lindaoak    |  last reply



strong electromagnets that repel each other?

I have two electromagnets already but they aren't strong enough to really push each other. I've read mixed things online about electromagnets that repel being very weak. I would like to build something like a shock absorber with a electromagnet at each end so when their is a load on the shock absorber the electromagnet can push back and stiffen. Any ideas on this would be awesome, i've spent a lot of hours researching online already but cant seem to find good info.  Thanks

Question by chrisack    |  last reply


how to make an EMP (electromagnetic pulse) ?

i want to make an EMP without (transformers , high voltage capacitors , and of course not nuclear)

Question by top.boy    |  last reply