# Salvaging Magnets

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I am not much of a believer in free energy and every time I hear the term free energy I ask the question what is so free about it. Even if you make a perpetual motion device, you ether bought it or you made it. Is your time not worth anything, are the parts not worth anything, so where is the free energy?

As to getting more out of something than you put into it, Geothermal Heating is called 300% efficient. That is you put 100 watts into it and you get 300 watts of heat out of it. The truth is the heat always existed. You just spent 100 watts to move the heat from where it was, to where you want it. You didn’t create anything you just moved it.

Wind, hydroelectric dams, and solar generation, are going to be the closest to free energy you can get. Nature supplies the forces you can convert into useable energy by way of some device but you still need to build or buy the device. So no matter what it is not free but you can get out of it more than you put into it.

I am planning to build an Axial Flux Generator without buying as many of the parts I can muster but to do this I need magnets and it will cost me my time. This Instructable is a bout salvaging magnets without damaging them.

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## Step 1: Magnet Sources

Too many things to name have magnets; I get my magnets from old electronics like this Ghetto Blaster for no more cost than my time spent collecting and stripping the electronics. There are magnets in the motors, in the CD player, and in the speakers.

For the axial generator I want the biggest magnets in the ghetto blaster and they are on the speakers.

## Step 2: Salvaging the Magnets

Now you can use brute force to salvage the magnets but I find gentle persuasion much more efficient and you don’t risk breaking the magnets. Since almost all magnets are glued in place I use heat to remove them from what they are connected to or the rest of the speaker.

Start by removing the paper diaphragm and coil.

Just about any heat source will do, I used the burner on my stove to heat the magnets on the speakers. This just takes a couple minutes to melt the glue.

Once the glue is melted the speakers come apart as easy as pie, place the parts on something heat resistant to cool and you are ready for the next step.

## Step 3: Cleaning the Magnets

Once the magnets cool I clean them before I store them this also gets them ready for reusing. Cleaning the magnets is important as this helps sort them by size and the glue will throw off your measurements. I start with 120 grit sandpaper and place the sandpaper on a hard flat surface, and then I rub the magnet against the paper until the glue is removed.

Once I have cleaned the glue off the first side I flip the magnet over and sand the other side until the glue is removed.

Scrape and sand off any glue on the outside edges and sides then do the same for the inside edges and sides of the magnets.

The dust will cling to the magnets until you wash it off with soap and water.

## Step 4: Sorting and Storing the Magnets

Depending on how many electronics you strip, it can take quite some time to gather enough magnets to make one rotor for an axial flux generator. For a single three phase rotor and stator you need four poles or magnets for every three coils in the stator and chances are you will not get many magnets the exact same size.

I store my magnets stacked; although they are permanent magnets if you just throw them in a box over time it can weaken their magnetic fields.

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## 30 Discussions

BeachsideHank has it right. You can get powerfull ring or donut magnets out of microwaves. There are two on both sides of the magnatron tube. They are tricky to get to considering these things are surrounded by a sheet metal box that was not disigned to come apart. I've cut myself more than once on things that say "No user serviceable parts inside". Good luck.

I know this is an old comment, but those magnetrons can contain Beryllium Oxide, which can be a fairly harmful substance, with cancer, skin irritation and lung damage. Would not suggest opening it up.

Down load Geek on your phone, you might have to wait for the magnets to come onsale but you can get n52 easy and cheaply,

5 replies

That small flywheel on the left is from a small engine like a snowblower. Inside the rim you should find 2 magnets... If not that's why your machine doesn't run

For info. On the Supermagnete site they write that Neodym magnets lose most of their power when heated, and sometimes they don't recover totally.

5 replies

You shouldn't get any magnet very hot or the magnetic field dies.

Most get their magnetism back when they cool.

Other magnets that loose their magnetic field need to be exposed to a magnetic field to reestablish their magnetic field.

Helps if you do not let the magnets get very hot, just hot enough to weaken the glue, and staking while you store the magnets helps reinforce reestablish and stablize the magnetic field.

Very good text. Just complementing. The curie temperature is a denomination of a magnetic and desmagnec temperature. And curie temperature is variable to many coposition of magnetic. For exemplo neodymium die about >80 and < 400°C populars like HD magnet. Ferrite like old speaks about 450°C. Ok but the problem in my opinion is the especific butane fire like blue fire. Because your temperature is about > 1700°C of course the ambient presure o2 concentration and others components change this value. But I think maybe using water in the process you save all the power of the magnets and help to remove the glue. Sorry my English. But I just talk to helps maybe tou know every write here. But help others users like me curioso and needs some information to make work like your result . thanks for share for us.

It doesn't take much heat to weaken the glue. I never measured it but about 100 to 150 degrees. The steel parts take most of the heat and stacking brings back any magnetic loss.

You might like this video.

Good video helps to fully understand the process. I truly believe that you have the knowledge to do what you're proposing, I did not comment to offend, just alerting some details that may hinder their course, when other less experienced users want to replicate the results, and it does not have as much experience and knowledge as you have. When you say by the magnet on the stove fire, many users can simply let time more and lose the magnet, since however much it may be recovered magnetism in the same way that it can be lost, with the temperature curie , need a more intense magnetic field than that contained in the magnet, applying it to the same temperature curie. Making the process often unfeasible. Just suggesting to have due care with flames four times hotter than the Curie temperature. Overall this was, congratulations on the initiative of share their work. See you soon.

I thought you would like the "How It's Made" Video.

I watch the "How It's Made" TV program almost every day on the Discovery channel. They do shows on everything.

I used to collect magnets, I would feed them to my dog - the weird thing is, every time I came home from work he was always stood next to the fridge looking sad for himself.

Sorry - loved the instructable - but could not resist.