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 6 years ago  |  last reply 6 years ago


Draw Blood with Neodymium Magnets.

I was curious if anyone besides me has drawn blood while playing with Neodymium Magnets?   Fortunately, it wasn't my blood..  On the down side, I'm no longer permitted  to play with powerful magnets when my Girlfriend Comes over.   She forgave me, but Electromagnetism is a Sore subject around here.

Topic by John_the_Builder 5 years ago  |  last reply 5 years ago


WANTED: Free Large/Medium-Sized Neodymium Magnets

Hello I am looking for large or medium-sized neodymium magnets that you no longer want or need. Magnets of more than 1in are preferred but magnets of a slightly smaller size are ok. The preferred shape(s) of the magnets is/are cube, bar, sphere, or cylinder but any shape is perfectly fine. Thank you very much for taking the time to look at this post, whether you can provide any magnets or not. Please reply if you can provide any magnets. I am willing to pay shipping if it isn't too high. Thanks again and have a great one. Bye! :) Side note: I am well aware that magnets are relatively cheap online but I need to get a large amount of large to medium-sized neodymium magnets and the price adds up very quickly so please think about giving me some magnets.

Topic by BeekerButts 2 years ago  |  last reply 2 years ago


How do I grind up demagnetized neodymium magnets? Answered

I need to know so I can do a project oh and I cant think of a way aside from using a blender

Question by nerd7473 5 years ago  |  last reply 4 years ago


how to make magnet motor free enrgy w/o neodymium? Answered

I dont have access to buy neodymium or much parts like roms and hard drive to slavage dozen of it. all i have are craft magnets.. ceramic type i think...

Question by No-Shi-De 8 years ago  |  last reply 4 years ago


How do I know the grade of a magnet?

I salvaged two identical neodymium magnets from an old CD rom drive. They're really strong and I suspect it to be neodymium, but is there any way to ascertain the "grade" of this magnet? Neodymium grades go like N35, N33,  etc...

Question by Power-Inside 5 years ago  |  last reply 5 years ago


Does a neodymium magnet harm an Iphone? Answered

I tried gluing a magnet on my phone case and I experienced some problems with Compass app.Except the compass effect is it safe to use it for a longer time?

Question by kaanthegmr 3 years ago  |  last reply 3 years ago


How are spherical rare-earth magnets manufactured? Answered

A question came up the other day when playing with Buckyballs of how you manufacture spherical rare-earth magnets. I'm surprised they could use that name, given the original Buckyball, but these Buckyballs are powerfully magnetic spheres with one side a North pole and the other a South pole which can be stuck together to make 2D and 3D structures.  Sale has been restricted in many places because of people ingesting them and requiring emergency surgery. I've found information on neodymium magnet production using a sintering process, but can't see how you could produce a perfect Ni/Cu plated sphere with this method as individually machining to a sphere would be excessively laborious and tumbling would be a non-starter because of the attraction between balls.  EDIT: The sintering page wasn't the one I thought I was linking, but the one I've linked looks like it may have the answer in die-pressing or isostatic pressing in the aligning field of a solenoid.  Is this how it's done for spherical magnets? (Polishing the coated spheres would still be a problem.)

Question by AndyGadget 6 years ago  |  last reply 5 years ago


What is the best design for an electromagnet in a pulse engine?

I am a complete bigger to all magnets, electromagnets, and electronics in general. Recently I've had an interested in different electric motors and have been looking into trying to make a pulse motor that is both efficient and powerful. To do this I want to be able to have the best arrangement of the magnetic fields of the neodymium magnets on the spinning disk and the electromagnets on the outside. I started playing around with the magnetic calculator found on https://www.kjmagnetics.com/calculator.asp but I don't really know what I'm looking at, just that different shapes and sizes have different fields and strengths.  Since a pulse motor is built by using an electromagnet to repel a neodymium magnet, what would be the best design for a strong burst electromagnet in the direction it's repelling the neodymium magnet? Also, what would be the best shape for the magnet to have the biggest repelling effect from the pulsing electromagnets? 

Question by AlanR18 3 years ago


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 9 years ago  |  last reply 8 years ago


Can permanent magnets cause interference when placed alongside cables? Answered

I'm wondering if I can safely use neodymium disc/button magnets alongside cables without causing interference? I know that interference can be induced from an alternating magnetic field e.g. transformer coils, but not too sure if a magnet in a fixed position would have the same effect? There's a project that I have in mind that would use these magnets to secure a fabric around cables holding them together. A single 5mm button magnet on one edge of the material would attract to a metal disc embedded in the opposite edge. The cables will mainly connect to audio / visual equipment so it's important to avoid any interruptions or distortions of the signal along the way. Can anybody help?

Question by DELETED_Alexdlp 8 years ago  |  last reply 8 years ago


Has anyone experimented with neodymium magnets as pole pieces in a single coil guitar pickup?

I have done some modification on pickups and preamps using opamps to amplify the signal. Since neodymium magnets are more powerfull than what they normally put in pickups I wonder what kind of sound would be generated?

Question by sn3102 9 years ago  |  last reply 9 years ago


what is the best way to make an induction charging system?

Using Neodymium magnets on the spokes of a bicycle rim, and coil around both forks.

Question by Alanclark1966 6 years ago  |  last reply 6 years ago


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 4 years ago  |  last reply 4 years ago


Power supply for a strong solenoid (recoil simulator)? Answered

Ok, I need a power supply for a solenoid. It is to simulate the kick of a pistol. I need a power supply that is small, so that I can hold it in my hand without being to heavy to hold for a long time or it being uncomfortable. The solenoid will have a neodymium rod made of lots of 6mm*3mm neodymium magnets inside it. The coil is 5cm long with 0.8mm ECW and 7 layers although it can be rebuilt. The point is that I need something to power this coil and let the neodymium magnets hit the wall behind the coil (wrapped around a 6mm tube) and produce a sort of kick. The power supply needs to run on a roughly small power such as two nine volt batteries (dc). This is a long question but I would greatly appreciate any help. Thanks :) (I have a circuit to make it produce recoil (electic bell...) but how will I power it to be powerful enough!?) Thanks again!

Question by Digital Flame 4 years ago  |  last reply 4 years ago


Should I use a Capacitor or Rechargeable battery for my shake light? Answered

I built a solenoid and am using a neodymium magnet to produce the voltage. I can get 5 volts easily, but I don't know what to use to store it. I am using a LED with a Vf of 3.3 and would ideally like the storing device to discharge slowly. What would be my best bet: A Rechargeable battery or a capacitor? I still need to get a rectifier, but if a Capacitor is recommended, how many farads should I be looking for?

Question by Dlanca1 8 years ago  |  last reply 8 years ago


Electricity Generator

Hi all,Quick question. If I attach Neodymium magnets to bicycle rim (separating it by waste rubber tube) and copper winding to bicycle mud guard how much electricity can be generated? What needs to be done to increase the same?ThanksViraj

Question by virajmoghe 1 year ago  |  last reply 1 year ago


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 7 years ago  |  last reply 3 years ago


Permanent Magnet Motor

I learned a couple of years ago about a motor developed by Nikolai Tesla that operates using neodymium magnets. If anyone has any information about this or other similar motors, please post information and help to save the earth from the evils of oil!

Topic by HazzardFan75 11 years ago  |  last reply 2 years ago


Coil inductor make?

I have, what I believe is, a neodymium ring magnet (pictured) that measures approximately 1.6 cm across x 0.3 cm thick and it has an inner diameter of of about 1 cm. I have been debating on what to do with it (also open to suggestions) hence the title. My question is how do I attempt to predict the performance of a coil created with this? 

Question by Dauntless 4 years ago  |  last reply 4 years ago


Magnetic Table Holds It All Together

All that space under your dining room table has been going to waste... until now! Install neodymium magnets all over the place and you have an interesting concept. I'd be in constant fear of knocking a cup and saucer onto the floor with my knee, but it's not like anyone's really gonna make this and use it. Right? linkvia Gizmodo

Topic by fungus amungus 11 years ago  |  last reply 11 years ago


Reducing home electricity bills by about 50% ? Answered

Can I reduce my home electricity bill by about 50% by using the following method :- Use an inverter to power an electric motor, the shaft of the electric motor rotates the armature of a AC generator with high number coils and powerful neodymium magnets. The generator recharges the inverter.   

Question by Jayvis Vineet Gonsalves 7 years ago  |  last reply 1 year ago


My students are making a shake charger using a coil.....? Answered

And a neodymium magnet.  Can I overlap the coil??  Meaning if I start at the left of the tube and coil to the right (clockwise), when I get to the end can I go right to left?  A few of my students are done already and their chargers aren't even lighting an LED.  Can anyone guess why?  Thank you so much! Patti

Question by mckywer 7 years ago  |  last reply 7 years ago


I'm using a 5V boost regulator?

To charge a cell phone battery.  BUT maximum current is 200 mA.  That's not enough current I'm assuming, right?  I need a continuous output of 5V but my students are most likely not going to get 5V from a shake charger (neodymium magnets going in and out through a coil of wire) which is why I was going to use a LM7805 but that needs 3 volts more than the output voltage.  Any suggestions??  Thank you!

Question by mckywer 7 years ago  |  last reply 7 years ago


How can I make a simple electric guitar? Answered

So I tried to make a very simple electric guitar today, using instructions from online. It was made from a board with two screws, a guitar string (steel) in between them, connected by copper wires on either screw to a small speaker. Under the string was a neodymium magnet. When I pluck the string, it says it should make a nice sound, however, I got no sound, and I verified with a multimeter that there was no voltage whatsoever. Here is a link to the discussion: http://www.mimf.com/archives/make_pickups.htm

Question by nsawyer2 7 years ago  |  last reply 7 years ago


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 1 day ago


Can anyone tell me for sure what material the Western Digital HD are made? They shine like mirrors and seems steel. Answered

I dismantled an old WD HD 2.5 Gb to use the neodymium magnet, and to my surprise I found that instead of a disc, it had three, stacked. I was also surprised for its mirror finish, I expected a dark brown surface, like floppies. Can anyone tell me for sure what material they are made the discs? Aluminum is not, must be steel, but it must be stainless steel or be well covered, because they shine like mirrors.  

Question by rimar2000 8 years ago  |  last reply 8 years ago


fake magnetic/shaker flashlight to real one?

Hi , I have a fake magnetic flashlight that had lithium batteries. anyway I decided to turn it into the real thing. I wrapped wire around it and replaced the piece of metal inside with strong neodymium magnet. It produces 20 to 100mv when I shake it.I have decided to use 1N5819 diode for full wave rectifier (is it better than 1N4007 ?) . What I need is the proper circuit for charging a 50mAH battery that I am going to use in it. any suggestions would be appreciated :-D

Question by ehsan_zt 3 years ago  |  last reply 3 years ago


Microwind Generator - any one up for the job?

Microwind Generator: 30X More Efficient and Cheaper!Popular Mechanics just held it's yearly Breakthrough Conference, and one of the winners was the Wind Belt an invention we've not seen before. The Wind Belthttp://digg.com/general_sciences/Microwind_Generator_30X_More_Efficient_and_CheaperSeems pretty simple!Anyone willing to make this?Things you might need... fabric, Neodymium magnets, and coilsYou can easily get good coils from led generators, even from the crappy 2 dollar ones. (As long as pumping it makes the led light on.)

Topic by akimbo m 11 years ago  |  last reply 6 years ago


Speakers

I have 4 speakers from the JBL On Stage ipod speakers that i want to rewire and use as portable speakers. I'd like to wire them together into a headphone cable so they can be plugged into a laptop and powered through the laptop or by batteries. I realize not all four may be able to be wired together so even just 2 or maybe 1 i'd be fine with. They are 1 inch in diameter each. Is it possible?? General Specs Drivers Four Odyssey Neodymium drivers Power Output 6 watts per channel Frequency Response 80Hz – 20kHz Input Impedance >5k ohms Signal-to-Noise Ratio >80dB Voltage Input 120 Vac U.S.

Topic by zed31415 10 years ago


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 5 years ago  |  last reply 5 years ago


Light Bulb Lamps

Oh what to do with the light bulb now that you're basking in the efficient glow of your CFLs? Well, you could convert them into these light bulb lamps as Sergio Silva has done. It's a pretty sweet item with neodymium magnets holding them in place on an included acrylic plate with embedded bits of steel.However, the price tag is $650 for the set which is pretty flippin' ridiculous for what can be remade with scrap and $10 of materials, if that. To be fair, the light bulbs Silva makes are sturdier than the regular item, are all made by the original artist, and are limited to a run of 66. So you're buying some design-y street cred before they get knocked off and sold for one-tenth the price. Linkvia bbgadgets

Topic by fungus amungus 10 years ago  |  last reply 8 years ago


Simple linear motor design ? Answered

I need a simple, not powerfull, linear engine. It has to move just like an inch back and forth, chaning directions on its own when it reached the end of his stroke. Even 5mm would be enough movement. I think about of something based on a neodymium magnet in cylinder shape. It has to be as simple as possible, i don't need any control for frequenzi, because if it works.. i can work out more from there on my own. Only thing important, it has to be small, like the lenght of a half pencil and 2cm in diameter would be ok (for the moving part, electronics placed elsewhere don't matter). A normal rotating engine with a shaft doesn't work for the design i have in mind :(

Question by wupme 10 years ago  |  last reply 10 years ago


Need help thinking of something conductive and magnetic? Answered

I am trying to attach some led lights under a shelf and also need to make them removeable, i need to find something that is conductive as well as magnetic. My original idea was to just get some small nickel or ? plated screws and just wrap wire around them and screw them in but not completely sure of that idea working. I already made the lights and have small neodymium magnets that im going to attach to them but just need some ideas of what to use for under the shelf....thanks Ive thought of clay, or glue and other stuff but idk. im putting 4 lights up. and there will be a switch to shut off power to the material when not in use so there's no safety issues.

Question by ARGMISTER 7 years ago  |  last reply 7 years ago


USB generator

I am building a small crank-powered generator for a college electronics class that will power a USB port. I know a USB port supplies 5V DC, and that my generator will obviously produce AC current, but I'm not sure the best way to convert AC to DC, then how to step my voltage up to 5 volts. My generator uses 6 wire coils in a circular pattern. 12 neodymium magnet rotate over the coils. This doesn't seem like the most efficient design ever, but that part is a stock university kit, the wiring is up to me. I've only been able to test each coil at a time, and each one produces .5-.7 VAC. Do any electricians out there have some tips? When all is said and done, I'll definitely be posting an instructable on this.

Topic by fortneja 10 years ago  |  last reply 8 years ago


magnetic bike pedals DIY? Answered

I'm Brainstorming a better magnetic pedal .   I know Proton and Mavic already make them But I'd like to have a Mag-Pedal that can be used with any shoe .    ... IDEA:  Using recycled neodymium magnets glued recessed into a gel insole  and magnets on pedals I'm hoping to make it easier than cleats on special shoes.  Of course you won't get the locked in power of straps or clippless cleats .This would be ideal for mud,gravel, quick commuting on regular bikes,bmx,mtb,people who what some full leg power on the up stroke but want to put your foot anywhere on the pedal you want.  Question: Might there be extra bearing ware from magnets?  Will there be enough magnetism through an inch of rubber to work??   Please critique my idea . 

Question by BtheBike 8 years ago  |  last reply 6 years ago


Will this electric generator idea work?

Will this work? A wheel that has neodymium magnets and coil of wire around iron, basically an electromagnetic. next to the wheel is a coil of wire that generates elctricity when the wheel turns, this coil conveys the electricity to the electromagnet through means of copper brushes. On the other side of the wheel is a coil of wire which gets electricity to power things. In my head, id say that the magnet powers the 1st coil then the 1st coil powers the electromagnet which also powers the 1st coil which powers the electromagnet even more. So in my theory, the electromagnetic gets infinitely powerful (till it burns out). So in a way the wheel can be cranked by hand and yet the 2nd coil will get a large amount of energy. Will this work in real life? why or why not? If this idea already exists what is the name?

Topic by alester333 10 years ago  |  last reply 10 years ago


Best magnet size to coil size ratio for an electromagnetic generator?

What is the best magnet (neodymium - disk shape) size to copper coil size ratio for optimal electron production per one break/pass of flux lines across coil at a 1/2" distance? For instance, if magnet is 2" diameter what is best inner diameter for copper coil? Best number of windings? Best gauge wire? what are the best specs for optimal electron production before you reach "over kill". I know some things are variable like core material and magnet grade. I'm looking for an all things being equal kind of scenario. Also what would be the best thickness of magnet at 2" diameter? If anyone could point me in the direction of any existing tables or ratio information on this subject it would be appreciated. Thank you.

Question by BishopKnight 9 years ago  |  last reply 1 year ago


Can you build a pmdc motor that can pull a skateboard prety fast on 240W?

I'm trying to build a pmdc motor (perminent magnet motor) based on this video: https://www.youtube.com/watch?v=WKklyuzghQg But I want to make it in a much biger scale and instead of using a ceramic magnet I wan to use 2 big industrial neodymium magnets instead they will pull up to 200 pounds. I want this homemade built motor to pull a scooter like vehicle (skateboard if you will). It will be powerd by 2 12V 10A batteries wich doing the math should get me: 12V+12V=24V 10A+10A=20A 24Vx20A=240W The coils will be made from 1.5mm thick copper wire. Based on what I've said do you think the motor could be powerful enough to pull this scooter with someone standing on it at about 20 to 25mph? can this be done?

Topic by NoahW7 3 years ago  |  last reply 3 years ago


How would a stronger magnet impact the performance of a speaker, and what impacts the overall quality of a speaker? Answered

Okay, so I had decided to build a sub-woofer for a speech topic for school, and I was wondering what it was that made speakers, or sub-woofers so loud an efficient. Granted, I know mine is far from great, while being made from ply-wood, duct-tape, and everything, but why is it that professionally manufactured speakers are so loud by them-selves with minimal power? I am using the circuits from my Logitech X-240 system, and the sub-woofer is always way louder than that of my home-made speaekr, with a significantly smaller ceramic magnet, it seems. Is it the geometry of the speaker itself, or what? What do manufacturers do in construction which improves the sound, or quality of speakers, and would using a neodymium magnet be better than using ceramic magnets? Any help is appreciated, and thank you in advance.

Question by XP1 7 years ago  |  last reply 7 years ago


Challenge: Can You Beat This Scary Turbine PumpkinCutter Halloween Project ?

This Halloween project is so scary that the inventor (myself) felt shock and awe at it. I was genuinely scared at the running of this machine...and rightly so! So I figured I would spread the scariness to all who see this machine, to set the mood for a DIY Halloween... The machine in question is what I have named the Tesla CD Turbine. The CD Turbine is magnetically-coupled to a Skilsaw blade. (What I teasingly call the PumpkinCutter Attachment). The Tesla CD Turbine uses recycled CD's and neodymium magnets for rotating parts...nothing else. It can rev up to thousands of rpm. It has no bearings or seals and is magnetically coupled to implements. It runs on either compressed air or water pressure. But hey, put on a magnetically-coupled Skilsaw blade, run it at thousands of rpm, and you have a very dangerous PumpkinCutter! (Instructable is ready...if you dare!) Beat that for a wild, scary, hi-tech, cheap and recycled Halloween project!!

Topic by mrfixitrick 11 years ago  |  last reply 11 years ago


I have a bunch of speakers what can i do with them? Answered

My car has enough speakers. My room has enough speakers. My wallet has enough speakers. And I don't know what to do with all these speakers. I have 10 mid range speakers, 2 tweeters, 2 sub-woofers, and 14 headphone speakers. Now I'm not really concerned with the headphone speakers because they're cheap and if they just sit in a bag for a while I'm fine with that but I'd like to put the nicer speakers to work. I don't want a surround sound system for my living room and I already have speakers there (not surround sound). I made the credit card speaker instructable. I'd like to do something with the speakers but at this point I'm thinking about just scraping them for their neodymium magnets because I can't think of what else to do with them.

Question by cdubnbird 9 years ago  |  last reply 8 years ago


How to add magnets to magnetic resistance exercise bike to increase resistance?

Hi, and thanks for reading my question.      We have just bought an exercise bike, it uses the pedalling to power the magnetic resistance of the bike. Here is the problem: at the highest setting, the resistance is still not very much.  We think that maybe we can increase the resistance by putting a strong permanent magnet near the flywheel, (we would cut a hole in the plastic cover to put the magnet near the flywheel). Can someone explain how to figure out how strong a magnet would need to be? How much "pull" would probably have a significant effect? What type (neodymium?), and what shape would work best (disk, rod, etc...?). We are willing to put about $50 into a magnet.   If this doesn't work I think I will remove the cover and just use a "friction wheel" sitting on top of the flywheel. really ugly, but it should work. Thanks for any help you guys can give!

Question by Urrgghh004 3 years ago  |  last reply 3 years ago


Needle valve on the cheap?

I need a needle valve or similar to adjust some pressure with more or less precision. Problems I am facing with commercial solutions at the moment: Needs to withstand about 300psi max pressure, must survive contionous exposure to concentrated ammonia vapour. I already wasted too much money on stainless steel valves claiming to be chemical proof and capable of 6000psi only to find out they use seals that turn to goo in the ammonia vapour and fail. And since the stuff is not really healthy, not easy to get, I would prefer something safer. Real problem is also that the thing should be able to allow for good flow rates when opened fully. Modes of operation: During the active cycle ammonia vapour needs to pass through an opening as big as possible while after that the flow must be shut off. The reverse cycle needs to be adjustable from closed to fully open with great detail to control the flow rate. Current ways to compensate: With a ball valves and extra piping I could seperate the two cycles so I won't have to bother with tiny openings but I would prefer to use only a single connection. With a bypass around the needle valve this could be accomplished better but still looks ugly. Materials out of the question: Copper, brass, normal seals based on rubber, nitrile or similar. Questions: I know fully sealed in.line valves exist for LPG system and similar. Are any of these magnetic valves available for the use with ammonia? And if so: Can they be operated with a neodymium magnet instead of the coil? Even stainless steel valves rated for chemical use and high pressure fail quickly on the seals. Is there anything available that does not use soft seals but for example aluminium instead? Thinking spray pump here... One way ball valve systems like used in simple spray pumps are a great thing. With some aluminium tubing I was able to make a simple valve that with some more attention to detail might even work. But of course there no other way of moving the ball then to use a magnet and with sufficient back pressure even neodymium ones fail to get the ball in the open position and keep it there. Now getting this combine with a needle... If, instead of the ball, a magnet in a teflon shell is used on a spindle I could spin a magnet around the outside to turn the valve with great precision. Has anyone already designed such a thing or would I have to start from scratch here?

Question by Downunder35m 2 years ago  |  last reply 2 years ago


Dual energy generation with magnetic Seesaw system and gravity with the help of 3 volt toy motor

This technology is based on  a Seesaw system and magnetic repelling principle Linear motion  .We can generate electricity with very little force with the help of this technology.This will be a radical step in the field of energy generation. In this technology there will be a balance system and two heavy weight magnets(high strength NEODYMIUM MAGNETS) will be attached with each side of this balance system as per diagram. As per diagram there will be two moving weights and these moving weights will move on tracks.These tracks will be fixed at the angle of 8 to 10 degree. Two magnets will be attached on the front side of these moving weights and these magnets will have similar polarity with the magnets of balance system. These moving weights will be attached with two gear boxes and these gear boxes will be attached with two generators. HOW THIS TECH WILL WORK? When one side heavy weight magnet of balance system will be pressed with the help of any kind of external force then this side will come down and repel its side moving weight due to equal polarity of magnets.due to repelling the moving weight will move forward .but when the heavy weight magnet will move upward then this moving weight will move backward due to gravity to get its position back. in this way this moving weight will work to run a gear box and this gear box will work to start a generator to generate energy. This balance system will also work to pass through their side copper coil due to linear movement and in this way this technology will generate Dual energy. WE will take very high strength NEODYMIUM magnets  for balance system. I would like to insist on some following points (1) The balance system will be attached with 'L' form crank with external PRESSING source. (2) The moving weights will also be attached with 'L' form crank with gear boxes. (3) Each side magnet of balance system will work one by one .When one side magnet will come down the another side magnet will move up .These magnets will come down and move up one by one to repel their side moving weight. (4) We can take as much weight as we can of these magnets of balance system .(500 kilogram to 1000 Kilogram or more) to pass through the heavy coils having 100000 turns or more.  (5) External source of pressing this balance system could be anything such as pressing with foot  or solar cell. WE WILL NEED ONLY 3 VOLT EXTERNAL ENERGY TO PRESS THIS BALANCE SYSTEM  AND GENERATE MORE AND MORE ENERGY.

Topic by vikram_gupta11 2 years ago


Outdoor electronic log drums.

We would like to make some outdoor drums made from logs that when hit trigger a relay which turns on a light. It it is proving to be very tricky to get a reliable system. We have tried using microphones with a small circuit to detect when triggered, these have worked the best but we get many false triggers and other times not triggering at all, we have tried adding pre amps to these microphones to try to boost the signal.  We have also tried to use capacitive touch sensors on top of the logs but again, many false triggers. The set up is installed outdoors for over a month and can sometimes be made to work but then the temperature and humidity will change and this causes them to false trigger or to not trigger at all, we are currently toying with the idea of hall effect or reed sensors, many of set into each log with a neodymium magnet in the end of the drum stick. If anybody has any ideas of how we can make a reliable system for installation outdoors that works through all the temperature and humidity changes please let me know. 

Question by mrhoopdogg 4 years ago  |  last reply 4 years ago


Materials Resources

It'd be helpful if we could create a permanent page to list recommended vendors of common supplies. If you have a favorite website for LEDs, magnets, electronics, or any other parts you could contribute to it. It would be a materials wiki, except one person updates it. An instructable wiki would be helpful as well, but one step at a time, eh?For example:PartsKlockit Clock movements and partspchcables.com One-foot USB extension cables (so common!)Tap Plastics Acrylics. Scrap bins in stores are a great resource.digikey Gobs of electronics.MagnetsK&J; Magnetics Neodymium magnets. Check out their surplus items and eBay auctions for deals.Printing & Cuttingblackbookstencils.com Lasercut stencils. Never used, looks good.[http:///www.calsilkscreen.com calsilkscreen.com] Excellent full-color vinyl stickers with cheap die-cuts (batches of 1,000)psprints.com Stickers are decently priced, but don't have glossy coat that protects them.overnightprints.com Really great full-color, double-sided, round corner business cardsSticker Guy $20 for 250 b/w stickers, but delivery can take up to 8 weeks.Otherocremix.org Great free remixed video game music

Topic by fungus amungus 12 years ago  |  last reply 11 years ago


Portable usb power supply for turtle beach X12 headset. Answered

I recently acquired a pair of X12's and they require usb power to run, I would love to be able to use them for applications outside sitting at my computer. I very little real experience with electrical power supplies, but I am almost sure that  most of the portable usb batteries that I have found put out too much for them too handle. Here are the full specs for them; Headset 50mm diameter speakers with neodymium magnets Speaker Frequency Response: 20Hz - 20kHz, >120dB SPL @ 1kHz Condenser Microphone Frequency Response: 50Hz - 15kHz Cable length: 16 ft. (4.87m) Weight: 6.4 oz (233g)        In-line Amplifier Headphone Amplifier: Stereo DC-coupled, 35mW/ch, THD <1%, Frequency Response: DC - 30kHz Bass Boost: Variable up to +12dB@150Hz Mic mute switch Maximum analog input level with volume control on maximum setting: 2Vpp (700mV rms) 3.5mm plug for line input 3.5mm plug for mic output 2.5mm XBOX 360® controller input jack USB connector for power (5VDC @ <60mA max) Dimensions: Height .5in (1.27cm), Width 2in (5.08cm), Depth .75in (1.905cm)

Question by aerinthaare 6 years ago  |  last reply 6 years ago


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 6 years ago  |  last reply 6 years ago


Aircon or fridge compressor to solar?

Sometimes I get weird ideas that I can't shake off :)When I was looking into options for a 12 compressor fridge freezer combo I was stunned.You a get a fullsized frrezer for far less!A further check revealed that it is mainly the linear compressor that makes the price plus the usual mark ups.Efficiency and especially start up is far better with thes compressors than out standard rotary and piston drive models.But why would it be so impossible to replace the motor from a standard compressor with a brushless DC one?I focussed on three things for the start:Lubrication, cooling and sealing.There is no such thing like a simple compressor with a piston system that does have some leaking.So apart from the noise the enclosure really needs to be welded and sealed again.Everything moving inside is lubricated by the drive shaft - it acts like a little pump.Same for the cooling of these vital parts.The oil flow exchanges heat through the big metal housing.A replacement motor would need to be suited to run in such a messy enviroment.Of course something to provide a proper oil flow needs to be created too if the drive shaft is replaced.With some basic enineering this might be possible, same for the motor mount and wiring to the outside.But what to do about the full load starting conditions that can happen?Even with no load from the cooling system the motor needs massive torque to get the piston moving.A bypass valve that closes once the motor is at proper speeds might work but hard to implement in a tight space.Any ideas?Did you ever try something that stupid?Could you make it work?What about a rotary compressor with external drive?We use ice blenders that have a magnetic base and the actual connection is made through the magnetic forces alone.A scroll compressor has lots of space without the original motor inside.Plus, a round pipe is easier to work with when it comes to adding or removing things.Small scroll compressors from an airconditioner or small industrial freezer wouldn't have to do much work in a small setup.Best thing is that with a variable speed the cooling power can be adjusted.How feasable would it be to use some polycarbonate end plate and a magnetically coupled drive ?Modern BLDC motors offer great performance and suitable gear systems are readily available.N52 neodymium magnets of the block type provide several kg of force if close enough to each other - should be enough to make a compressor spin...In return it could mean to have a nice freezer or even airconditioner that runs directly on solar power.No massive losses from inverters, no need for huge battery banks either.As long as the sun is out you have free power, once down you can still switch to a power supply for the motor or use battery power.Just imagine you come home after long day of work and the house is already cool.And you did not have to pay a cent to get it cool or wait for hours for it to reach this temperature!We love to add solar panels to our houses in the hope to get a few cents back from our energy providers.The sad reality often is that you might be able to power all your needs during the day but the excess that goes back to the grid often pays next to nothing.But if you could power a lot more things like a compressor directly with the electricity from your panels....Then these kWh would not appear on your usage bill either.Means you neither use what the power provider compensates you for nor is it "wasted" thorugh this bogus compensation.The normal solar setup can then provide you with this little extra money while an additional set powers the motors for your big freezer or little airconditioner - little being relative to what you make of the idea ;)If you really dare than you could even use your bike and legs to power your fridge directly ;)Use your imagination :)

Topic by Downunder35m 8 weeks ago  |  last reply 4 weeks ago