Author Topic: Electrical Demagnetizer  (Read 37006 times)

Offline Bernd

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Electrical Demagnetizer
« on: March 20, 2010, 12:15:34 PM »
First a warning.
WARNING: If you do not understand electricity do not attempt this. If you are afraid of being electrocuted you probably will be, DO NOT ATTEMPT THIS THEN Have an electrician wire this for you.

For a while now I’ve wanted to make a demagnetizer. I got tired of picking up one allen wrench and having one or two others attached to it. I saw a thread on HMEM a while back about a demagnetizing tooling. I though why buy one when you can make one out off some parts around the shop. What I’m using is a transformer or I should say part of a transformer out of a micro wave oven. The first picture shows all the parts need for a test set up.

On the bottom left is what a transformer from a micro wave oven looks like when all together. Notice it has two windings on it. The top winding is of lighter gage wire than the bottom. You need to disassemble the transformer and use the smaller gage wiring. Also you will need a bulb wired in series with the winding. This is in case of a short. The bulb will light brightly if there is a short. This is all temporary wiring and is not going to be used in the final version of this tool.


Here’s a drill that somehow has gotten magnetized.


I’ve plugged in the demagnetizer, you can see the faint glow of the spot light. As you get near the magnet you can feel the drill start to vibrate from the 60Hz frequency. Before you get it all the way through the chips have fallen off.


And there you have it. One demagnetized drill.


Now that I know this setup works it will be permanently mounted in a box with complete wiring and power switch plus a circuit breaker or fuse. All self contained.

Remember electricity can harm you. If you are in doubt stay away from it.

Bernd
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Offline websterz

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Re: Electrical Demagnetizer
« Reply #1 on: March 20, 2010, 12:44:05 PM »
The day after I drop $40.00 on a demag'er you go and show me how to make one.. :bang:
"In the 60's, people took acid to make the world weird.  Now the world is weird and people take Prozac to make it normal."
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Offline John Stevenson

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Re: Electrical Demagnetizer
« Reply #2 on: March 20, 2010, 02:40:29 PM »
I have heard of people taking the rotor out of a single phase AC motor and passing the parts thru the hole in the middle.

John S.
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Offline framey

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Re: Electrical Demagnetizer
« Reply #3 on: March 20, 2010, 03:22:32 PM »
cheaper option is to tap it on the side of something else thats how i always do it lol

Offline Bernd

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Re: Electrical Demagnetizer
« Reply #4 on: March 20, 2010, 03:34:11 PM »
The day after I drop $40.00 on a demag'er you go and show me how to make one.. :bang:

Sorry about that websterz, I could reinburse you the $40. How's a buck a month sound? (hidding under table)

John has also got a good idea, except his would be round.

I've tried banging against something else. All it did was remove the chips. The tool was still magnetized. :coffee:

Bernd
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Offline andyf

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Re: Electrical Demagnetizer
« Reply #5 on: March 20, 2010, 06:26:50 PM »
For small items like Allen keys and drills, I just pass them though the loop of a Weller soldering gun. Get them some distance away before releasing the trigger. Same with screwdrivers, though they have to be dipped in and out because the handle won't go through the loop.

And the loop is hot, of course, so watch your fingers.

Andy
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Offline websterz

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Re: Electrical Demagnetizer
« Reply #6 on: March 20, 2010, 07:46:32 PM »
I regularly make small batches (50 or so) parts out of 4140. After hardening and surface grinding them there is always some residual magnetism in them. I bought a 4x6 surface demag'er from Enco planning to spread the parts out on a thin piece of card stock and treating a whole batch at a time. Plus it will be big enough to do drills, hand tools, etc. Just under $40 with free shipping. Cheaper than scrapping my microwave I guess... :dremel:
"In the 60's, people took acid to make the world weird.  Now the world is weird and people take Prozac to make it normal."
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Offline Krown Kustoms

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Re: Electrical Demagnetizer
« Reply #7 on: March 20, 2010, 08:57:07 PM »
Nice utilization of scavenged parts.
I love seeing something so simple turned in to a tool.

So......are you using the bulb as a fuse/circuit breaker? I see it as a good indicator of a 'dead' short but are you going to utilize it in the perminant fixture?
A small neon bulb and a fuse would also act as a indicator to tell you if it was on or not.

I am already looking for a small transformer to build this 'need to have' tool.

Thanks for the idea. -B-
-B-

Offline 75Plus

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Re: Electrical Demagnetizer
« Reply #8 on: March 21, 2010, 07:31:16 AM »
I have an old bulk tape eraser from the 4 and 8 track days that does a good job of erasing the magnetism from tools and small parts. It also doubled as a degausser for the earlier color tv's that did not have automatic degaussing.

Joe

Offline Weston Bye

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Re: Electrical Demagnetizer
« Reply #9 on: March 21, 2010, 07:51:36 AM »
Where I work one of the maintenance technicians came to me with a steel detail that kept picking up magnetism causing the steel parts that it was supposed to guide to stick and not flow smoothly.  I made a quick demagnetizer from an automotive air conditioner clutch coil and a 12 volt, 3 amp transformer.  This was convenient because we make the coils.  The coil is a freestanding bonded coil, no bobbin or other supporting structure.  The nice thing about the coil-transformer arrangement is the low operating voltage.  The coil does get warm, but can be left on indefinitely without damage - after all, it was designed to survive the +140°C environment of the engine compartment.  Also, the coil has a large bore, allowing large or wide parts to be demagnetized.

If one were to be salvaged from an A/C clutch, the steel shell would have to be removed; carefully machined away on the lathe, mill or with a Dremel.
Weston Bye
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author of The Mechatronist column
Digital Machinist magazine

Offline John Stevenson

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Re: Electrical Demagnetizer
« Reply #10 on: March 21, 2010, 09:19:54 AM »
Trying to get simpler, what about using a torroid transformer on it's own ?

John S.
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Offline Bluechip

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Re: Electrical Demagnetizer
« Reply #11 on: March 21, 2010, 09:50:27 AM »
J S

Don't think it would work .. all the magnetic flux is in the toroid .. or should be ..

Dave BC

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Offline Bernd

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Re: Electrical Demagnetizer
« Reply #12 on: March 21, 2010, 12:44:49 PM »
I regularly make small batches (50 or so) parts out of 4140. After hardening and surface grinding them there is always some residual magnetism in them. I bought a 4x6 surface demag'er from Enco planning to spread the parts out on a thin piece of card stock and treating a whole batch at a time. Plus it will be big enough to do drills, hand tools, etc. Just under $40 with free shipping. Cheaper than scrapping my microwave I guess... :dremel:

Being close to a transfer station (junk drop off) I've picked up the dead micro-waves. I've got at least a dozen or so transformers.

The reason I started collecting these was/is I found an article on the net about making your own spot welder using two rewound transformers. I've got the article stored some were on my disk drives.

I'm sure you could find them laying out on the curbside on pickup day.

Bernd
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Offline Bernd

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Re: Electrical Demagnetizer
« Reply #13 on: March 21, 2010, 12:53:41 PM »
Nice utilization of scavenged parts.
I love seeing something so simple turned in to a tool.

So......are you using the bulb as a fuse/circuit breaker? I see it as a good indicator of a 'dead' short but are you going to utilize it in the perminant fixture?
A small neon bulb and a fuse would also act as a indicator to tell you if it was on or not.

I am already looking for a small transformer to build this 'need to have' tool.

Thanks for the idea. -B-

I learned this trick back in my early days of model railroading. The club I belonged to used an automotive bulb of a certain size in there power to the track. Shorts occured many times through in the wiring because people would throw the wrong swtich. So instead of buring out power supplies the light would light up and show a short indication. This method never let the magic smoke out.

So concider the bulb as a sort of indicator. If the coil develops an internal short the bulb will light up giving an indication of such. A fuse should always be incorporated into a system like this along with a power on indicator light.

Another thing that's useful is the very, and I mean very, strong magnet that is incorporate with the micro wave emitter. About as strong as the magnets in a disk drive. They are useful also. Another little how to I want to post eventually.

Now all I need to do is make it permanent. And of course with my project list being as long as some criminals arrest list..... well you know the rest.  :lol:

Bernd
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Offline Darren

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Re: Electrical Demagnetizer
« Reply #14 on: March 21, 2010, 03:10:50 PM »
Nice idea Bernd, my only concern is the voltage on the second winding on a microwave transformer. Usually around 11Kv from the ones I've tested.

I don't suppose the voltage of the transformer makes too much difference for de-magnetising so perhaps a 12V one would be safer?

Just a thought ...

JS, Dave is right, you can't get inside the windings on a toroid like you can with an EI transformer coil ...  :thumbup:
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Offline John Stevenson

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Re: Electrical Demagnetizer
« Reply #15 on: March 21, 2010, 03:18:25 PM »
OK, it's just that the torroid already has a big hole in the middle so I thought............ and thought...... OK forget it  :wave:

John s.
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Offline Bluechip

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Re: Electrical Demagnetizer
« Reply #16 on: March 21, 2010, 07:38:53 PM »

Hi Troops

Mine was made from a defunct pistol drill. The armatures usually go Pfttt. leaving the stator OK.

They often have two screws holding 'em together, just cut one out to make the air gap as per attached C-O C.

(Yes, I know it's not very convincing Mr. Stevenson, to professional Electric Motor Consultants, look upon it as a 'Generic Artists Impression' ..   :scratch:)

Put a bit of U-shaped plastic to make a trough, draw the driver/whatever through a few times.



Used to work, I used it with a Variac, but just stick a 60/100W filament lamp in series with the contraption to limit the current.

Bernd.. good scheme using lamps to limit current, specially made ones were used on the 80-0-80 VDC telegraph signalling supplies, called Baretters.

Darren.. didn't think Microwave Trannies went that high, about 2kV?, unless they wind up off load? No matter, you're dead anyway .. rare or bien cuit, it's curtains.

Dave BC
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Offline John Stevenson

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Re: Electrical Demagnetizer
« Reply #17 on: March 21, 2010, 07:57:01 PM »


(Yes, I know it's not very convincing Mr. Stevenson, to professional Electric Motor Consultants, look upon it as a 'Generic Artists Impression' ..   :scratch:)


Dave BC

I much prefer 'Bodger extraordiniar ' instead of Electric Motor Consultant :wave:

Darren, I thought the microwave idea was to gut the tranny and just use the mains input coil and dump the nasty singed bollocks bits ?

John S.
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Offline Darren

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Re: Electrical Demagnetizer
« Reply #18 on: March 21, 2010, 08:03:26 PM »
Dave, you are right ... I missed the point.... decimal that is  :doh:

John, I suppose if the laminations are removed then there can be no secondary voltage? So Bernd, sorry, you are prob quite ok with what you have done. If I remember rightly (it's been quite a while since I looked at a micro tranny)  are the two coils are side by side and not one on top of the other as in normal windings. Therefore you could separate the HV coil.

Is that what you did Bernd?

Edit, went back and had another look, yes I can see you have only used the primary coil. 110v or 220V ? Forget what I said earlier about the HV coil. Except that anyone playing around with one of these should realise that before they pull it apart the secondary coil can kill you in an instant if you power it up and get a Zap  :zap: :thumbup:

Last time I was playing with these I was powering some old radio valves, now I have a nice 4.3KV transformer with a 3.2Kv tap that weighs 57Kg (decimal correct this time  :) )
« Last Edit: March 21, 2010, 08:10:09 PM by Darren »
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Offline Bernd

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Re: Electrical Demagnetizer
« Reply #19 on: March 21, 2010, 08:04:52 PM »
Nice thought Darren. Will have to run it through my auto-transformer (variable voltage transformer) to see. As long as it's AC voltage.

Added after reading your message: If you take a look at the original picture you'll see that the transformer on the left is what comes out of the micro-wave oven. The top coil is the primary or mains. It has the larger dia. wire. The secondary has the smaller wirer. As you'll notice in the second picture that all I have is the secondary coil. The one with the finer gage wire. I tried the primary/mains with the lamp in series and the bulb lite up brightly and almost no magnetism in the coil.

Yes, you do need to seperate them. The reason I seperated them was I had to prove to a neighbor who does scrapping he can get about 4 pounds of clean copper out of them. You need to grind out the weld that holds them together.

Bernd
« Last Edit: March 21, 2010, 08:14:17 PM by Bernd »
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Offline John Stevenson

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Re: Electrical Demagnetizer
« Reply #20 on: March 21, 2010, 08:09:24 PM »
Darren,
i was just going on the pic's in the first post.
Example tranny on the left and then the rest of the pics with an open coil, no laminations, that's why i suggested a torroid.

John s.
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Offline Darren

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Re: Electrical Demagnetizer
« Reply #21 on: March 21, 2010, 08:13:36 PM »
John,

I still don't think it would work as you cant remove the laminations to get inside the coil. The center hole in a toroid isn't the same thing as far as I know?
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Offline Bluechip

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Re: Electrical Demagnetizer
« Reply #22 on: March 21, 2010, 08:15:29 PM »


(Yes, I know it's not very convincing Mr. Stevenson, to professional Electric Motor Consultants, look upon it as a 'Generic Artists Impression' ..   :scratch:)


Dave BC

I much prefer 'Bodger extraordiniar ' instead of Electric Motor Consultant :wave:

Darren, I thought the microwave idea was to gut the tranny and just use the mains input coil and dump the nasty singed bollocks bits ?

John S.

Surely Master Bodger Extrordinaire ?      M.B.E.  ....

Bend of knee, tug of forelock etc ?

Dave BC
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Offline Darren

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Re: Electrical Demagnetizer
« Reply #23 on: March 21, 2010, 08:17:51 PM »
Ah, I seeeeeeee Bernd, yes the secondary coil would have more turns and a higher field.

And a higher resistance for the mains circuit, jolly good thinking Batman  :clap: :clap: :clap:
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Offline Bernd

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Re: Electrical Demagnetizer
« Reply #24 on: March 21, 2010, 08:18:45 PM »
This may answer some questions about toroidal transformers - http://en.wikipedia.org/wiki/Transformer

Bernd
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Offline John Stevenson

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Re: Electrical Demagnetizer
« Reply #25 on: March 21, 2010, 08:21:54 PM »

Surely Master Bodger Extrordinaire ?      M.B.E.  ....

Bend of knee, tug of forelock etc ?

Dave BC

I already have the MBE, stands for Motor Bike Engineer  :lol:

John S.
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Offline Bluechip

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Re: Electrical Demagnetizer
« Reply #26 on: March 21, 2010, 08:26:32 PM »
JS


MBE2 ?

Dave BC




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Offline John Stevenson

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Re: Electrical Demagnetizer
« Reply #27 on: March 21, 2010, 08:41:53 PM »
JS


MBE2 ?

Dave BC






Brilliant I like that.   :smart:

John S
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Offline websterz

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Re: Electrical Demagnetizer
« Reply #28 on: March 21, 2010, 09:18:22 PM »
...  (it's been quite a while since I looked at a micro tranny)...

In THAT case Darren...I have a little gift for you.



 :bugeye: :lol: :doh:
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Offline Darren

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Re: Electrical Demagnetizer
« Reply #29 on: March 22, 2010, 04:15:06 AM »
You have to wonder what some people get up to in their spare time, now I know .....















Utube .....  :lol:
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Offline websterz

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Re: Electrical Demagnetizer
« Reply #30 on: March 22, 2010, 04:19:08 AM »
You'd be surprised at how difficult a micro tranny is to actually FIND these days! I spent a half hour looking for that little gift for ya'.  :lol:
"In the 60's, people took acid to make the world weird.  Now the world is weird and people take Prozac to make it normal."
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Offline ScroungerLee

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Re: Electrical Demagnetizer
« Reply #31 on: March 22, 2010, 11:16:20 AM »
Bernd,  any idea how many ohms that coil measures?

Thankee

Lee

Offline Bernd

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Re: Electrical Demagnetizer
« Reply #32 on: March 22, 2010, 02:45:56 PM »
Bernd,  any idea how many ohms that coil measures?

Thankee

Lee


Yup, 62.7 ohms

Bernd
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Online John Hill

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Re: Electrical Demagnetizer
« Reply #33 on: March 22, 2010, 04:09:00 PM »
I have a bulk tape eraser from the time when we used 1" wide magnetic tapes.  As far as I can see the eraser is a single coil wound around a 'E' shaped stack of laminations.  I know the core of a transformer is usually made of laminations of shapes 'E' and 'I' stacked alternately so if you can get one apart you could reassemble with just the 'E's.

If you have a stable load, like a coil, which does not have enough resistance/reactance to limit current flow you could use a resistor (or a light bulb) to limit the current flow  but you can also use a mains rated capacitor in series, the smaller the capacitor the lower the current.
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Offline madjackghengis

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Re: Electrical Demagnetizer
« Reply #34 on: March 25, 2010, 10:08:55 AM »
Hi ya'all, I just wanted to say there is an even easier, and safer way, which is probably also cheaper, which is to take any of the kind of small ac motors, such as a phonograph motor or small fan motor, which has a shunted "stator", which you will see as a thick copper wire wrapped around the stator in a couple of places, remove the bearings and the rotor, and cut a slot wide enough for the biggest thing you want to demagnetize, either put a switch in the circuit, or unplug it to turn it off.  To use, plug it in, take what is magnetized, and put it between the two poles you left, and slowly draw it away from the motor stator until it is a couple feet away, and then turn it off or unplug it.  If you do exactly the same thing, but unplug or turn off the stator while the piece of steel is between the poles, you will very effectively magnetize it most of the time, unless by luck you switch it off while the coil was in a null of the a/c wave.  I worry about microwave transformers, because if you don't do something with the small wire side, which is the high voltage side, it can easily reach above a thousand volts on "flyback", as it is made to drive a magnetron to make microwaves, like radar.  They are great for making the primary power supply for a really powerful Tesla Coil if that is what you're into though.  My demagatizer has a stator that's about an inch and a quarter thick, and will demagnetize a six or eight pound chunk of steel easily, and I haven't bothered to be safe, I just plug it in, and un-plug it.  Opening up where the rotor goes, and leaving two poles which are a fair distance apart makes the shunted motors very efficient for magnetizing and demagnetizing, and they need no current control, which is what the light bulb effectively does.  Mad Jack

shaded pole fan motor with cord

another view, showing the hack saw cuts, to provide good poles.
« Last Edit: March 31, 2010, 08:33:48 AM by madjackghengis »

Offline wheeltapper

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Re: Electrical Demagnetizer
« Reply #35 on: March 25, 2010, 11:06:56 AM »
Hi all
Iread this thread 2 days ago and thought "what a good idea".
yesterday my neighbour said to me " my microwave oven just packed up, would you like it for the bits inside "

"not arf" says me :D

so here's my version,

inside


and outside


the box cost a couple of quid in B&Q
the rest was lying around, as it does :lol:

the coil is held down with cable ties. works a treat.

cheers
Roy
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Offline Bernd

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Re: Electrical Demagnetizer
« Reply #36 on: March 25, 2010, 12:15:28 PM »
Hey nice Roy.

Ah Mad Jack I've got to give one of these  :wack:

Go back and look at my OP. Notice that I use the coil with the finer wire, not the whole transformer. I remove the secondary coil and use it be itself. I was just showing what that transformer looks like when removed from the micro wave oven.

Remember the magnets in the magnetron are also good items to save.

Bernd
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Offline wheeltapper

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Re: Electrical Demagnetizer
« Reply #37 on: March 25, 2010, 12:20:21 PM »
Yea, I got the magnets out as well.
thinking about it, I make something to DEmagnetise things then save 2 ruddy great magnets.
I must be mad.

incidently, if you have a mechanical wristwatch, TAKE IT OFF before switching this gadget on!!

cheers
Roy
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Offline madjackghengis

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Re: Electrical Demagnetizer
« Reply #38 on: March 31, 2010, 08:42:13 AM »
Ah Bernd, using just the secondary means you get to use the transformer without a core, and with enough impedence as to prevent buring up the coil.  I save those microwave transformers in case I need to hurt someone someday, you can never be too paranoid, and they are out to get you!!  Properly used, that transformer, the magnetron, and some artful wiring to an inverter and you've got a radar gun disruptor and probably disrupting all sorts of microwave communications, and maybe even wireless computers.  Might be valuable to keep around.  Mad Jack  P.S. I think I got my fan motor with the "shaded poles" off the same microwave, don't throw anything away, that's my motto!  Be Prepared!

Offline Bernd

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Re: Electrical Demagnetizer
« Reply #39 on: March 31, 2010, 08:53:07 AM »
Hey Mad Jack. Sounds like my kind of thinking on the transformer. That would be an interesting project.   :dremel:

Bernd
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Offline madjackghengis

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Re: Electrical Demagnetizer
« Reply #40 on: April 05, 2010, 09:48:43 AM »
Hey nice Roy.

Ah Mad Jack I've got to give one of these  :wack:

Go back and look at my OP. Notice that I use the coil with the finer wire, not the whole transformer. I remove the secondary coil and use it be itself. I was just showing what that transformer looks like when removed from the micro wave oven.

Remember the magnets in the magnetron are also good items to save.

Bernd
Ah Bernd, I was speaking of "flyback", which can and does occur in a single coil, in the right (or wrong) circumstances.  With that great big coil of fine wire, opening contact suddenly can give an induced high voltage pulse just as an ignition coil does, even without a second coil just from the collapsing magnetic field.  The addition of field pieces with a gap between them also improves the efficiency of the magnet as well.  If I remember right, the fan motor I used in the picture, came out of a microwave oven.  I save that high voltage transformer for the day I have to power the magnetron with it, to interfere with official radio communications and stave off the invasion of the aliens.  Mad Jack

Offline madjackghengis

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Re: Electrical Demagnetizer
« Reply #41 on: April 05, 2010, 10:05:47 AM »
Hey Mad Jack. Sounds like my kind of thinking on the transformer. That would be an interesting project.   :dremel:

Bernd
Bernd, there is a capacitor of high voltage across the magnetron, which is half a tuned tank circuit, with the transformer and the inductive load of the magnetron being the other half of the tank circuit.  Connecting it all up as it was in the original, with a spark gap installed in this high voltage circuit with the gap adjustable with a wooden handle of some sort, and getting it adjusted to where it crackles rather continuously, gives a high output of RF, and very odd and changing high frequencies, that is RF wise, about as noisy as it can get.  You do need a disc reflector of some sort on the "nozzle" output of the magnetron, to provide a "ground plane", which closes the high frequency circuit allowing the nice crackling effect.  The out put of the transformer can be run through the primary of a good high voltage car coil, and its output run into a nice dome or the like, again with an adjustable spark gap, to generate the oscillation, and you have a medium sized Tesla coil which ought to approach half a million volts or so.  Running the output of the transformer into a conventional shallow cone primary coil, with a 100 to one "tower coil" as is standard for Tesla coils will get a really good effect, and probably close on to a million volts, again with an adjustable gap.  That's just for people who really enjoy playing with high voltage and aren't afraid to die.  Working around radar too long can give a person a bad attitude toward high voltage, and a lack of proper respect.  Mad Jack

Offline Bernd

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Re: Electrical Demagnetizer
« Reply #42 on: April 05, 2010, 06:53:43 PM »
Yup, understand about the fly coil. But you got me beat on all the other info.

Guess I won't try for the high voltage, bad heart ya know.  :lol:

Thanks for explaining though. Didn't know you have such an extensive background in "electricity".

Bernd
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Offline madjackghengis

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Re: Electrical Demagnetizer
« Reply #43 on: April 09, 2010, 11:36:07 AM »
I regularly make small batches (50 or so) parts out of 4140. After hardening and surface grinding them there is always some residual magnetism in them. I bought a 4x6 surface demag'er from Enco planning to spread the parts out on a thin piece of card stock and treating a whole batch at a time. Plus it will be big enough to do drills, hand tools, etc. Just under $40 with free shipping. Cheaper than scrapping my microwave I guess... :dremel:

Being close to a transfer station (junk drop off) I've picked up the dead micro-waves. I've got at least a dozen or so transformers.

The reason I started collecting these was/is I found an article on the net about making your own spot welder using two rewound transformers. I've got the article stored some were on my disk drives.

I'm sure you could find them laying out on the curbside on pickup day.

Bernd
Hi Bernd, I have to say it felt good to catch you off guard with the fifty one hole index plate!  I was wondering if you ever did anything with the idea of the spot welder, or have any other experience with a spot welder.  I've got a top of the line ESAB welding power supply I use mostly for tig but occasionally for stick and have been considered using it, as it is all solid state, with a solid state contactor setup.  I haven't tried it yet because I seldom need to spot weld, and usually plug weld instead, so far, however if I had a good, solid set up, I would spot weld pretty often if it were convenient.  By the way, I assume your avatar is a scale model, do you have a build log or some more pictures showing more of the truck?  mad jack, out in the noonday sun, again!

Offline Bernd

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Re: Electrical Demagnetizer
« Reply #44 on: April 10, 2010, 09:45:49 AM »
Mad Jack,

I used to to do quality control on first parts coming off cnc machines. One job was checking holes on a bolt circle. So I had to figure out the  X & Y settings for the coordinate checking machine. That''s when the light came on when you said "coordinate" and the drilling the holes. Ya! I can do that.

I haven't done a thing on building the spot welder. Really no need for it. But if you interested I'll see if I can find it.

The sotry behind the avatar. That picture came out of the August 1975 Hot Rod magazine. Back then I was quite interested in cars. That truck is a total scratchbuilt vehicle. I just like the design on the old Mack trucks. Here's a pic with the full story. The guy has a web site. Google "low buck tool" and read about the way he got started.



Bernd
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