# Has anyone made an electro magnetic chuck from the guts of a microwave?



## Janderso (Jul 29, 2020)

I saw this video this morning.





It got me thinking, I can do that. For a drill press or a bench fixture!!
Have you made one?


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## Winegrower (Jul 29, 2020)

Wow, that is interesting and amazingly clever.  But man, that guy really needs a milling machine!


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## mmcmdl (Jul 30, 2020)

Got anything you can make out of a old dishwasher ?


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## Lo-Fi (Jul 30, 2020)

mmcmdl said:


> Got anything you can make out of a old dishwasher ?



A parts washer!


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## mmcmdl (Jul 30, 2020)

The thing leaks somewhere ! Besides , if it isn't good enough for the kitchen , it sure won't go into the garage !


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## NortonDommi (Jul 30, 2020)

mmcmdl said:


> Got anything you can make out of a old dishwasher ?


Bidet?


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## Karl_T (Jul 30, 2020)

KEWL!

Say will most any transformer work? I have several large ones out of old CNC machines, physically four times bigger.


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## Janderso (Jul 30, 2020)

Winegrower said:


> Wow, that is interesting and amazingly clever. But man, that guy really needs a milling machine!


Just think what he could do with a machine shop.
He did a nice job and it appears to hold very well.


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## ttabbal (Jul 30, 2020)

Karl_T said:


> KEWL!
> 
> Say will most any transformer work? I have several large ones out of old CNC machines, physically four times bigger.




I don't see why not. The design just uses the laminations as a core for an electromagnet. Some transformers are pretty easy to disassemble, using rivets or bolts instead of welds to hold the core together. If you have that type, it would be easy enough to test.


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## homebrewed (Jul 30, 2020)

In this application the windings are driven with DC.  Laminated cores are used to reduce eddy-current losses when the the core is used as a transformer, which is not the case here.  So you could also make one of these just using soft iron pieces and winding your own coil(s).  To concentrate the magnetic field where you want it, you want the magnetic-field path to be gap-free so the fingers of the "E" need to be machined flat, along with the mating surfaces on the long portion of the "E".  I'd be inclined to screw them together, but welding would probably work, too.  Long portion:  the | (vertical) section.  The fingers:  the "--"  (horizontal) pieces.  Of course, in use the "E" would be rotated so it is a "dead E"   .

I'm reminded of a really old (and bad) physics joke.  If an "M" represents a centimeter, what does a "W" represent?  Answer: a dyne-centimeter.  UGH!


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## rwm (Jul 30, 2020)

It looks like he is using only the secondary windings? Does he say what voltage and amperage he is using thru these? Is it line voltage?
Robert


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## nnam (Jul 30, 2020)

I really like the idea.  He uses the larger diameter wire coils, throw away the smaller one.

Hope to make one one day


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## nnam (Jul 30, 2020)

rwm said:


> It looks like he is using only the secondary windings? Does he say what voltage and amperage he is using thru these? Is it line voltage?
> Robert


12 v, 10 amp. looks like DC


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## brino (Jul 30, 2020)

I have not made a chuck, but I did make an electromagnet for a demonstration. It was very easy.
It was a kids science thing, I had demos of Lens' Law, a home-build hand-crank generator (magnets and coils), wireless power, a Jacob's ladder from an old furnace transformer, etc.

I based the electro-magnet on two videos I saw.....I will try to dig them up. One showed a home-made mag-drill based on one of these magnets.

Newer microwave ovens use much smaller parts.
I went to the local recycle centre and borrowed a couple big, old microwaves from the pile. I took them home removed the transformers and took them back.



rwm said:


> It looks like he is using only the secondary windings?



Right! I cut off the primary windings.

In the demo I had this electomagnet with a big handle on it powered by two AA cells in series; only 3VDC!
You could stick the magnet to a 4"x12" piece of 1/4" flat steel stock, flip the switch, stand on the steel and not be able to pull the magnet off!
Flip the switch again and it lifts right off.

Only one person was able to pull it off and that was late in the afternoon, so I switched to the second set of batteries, and again no one beat it.
That did surprise me; only two sets of batteries for a day's worth of demos.

-brino

EDIT: I looked it up, I recorded 3Amps at 3Volts and was able to lift over 100lbs of steel. With a better power supply, (maybe 12V?) I think it would make a grinder chuck.


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## Janderso (Jul 30, 2020)

You guys seem to know what your talking about.
Once I find a used microwave, I'll be consulting you guys.
DC? He hooked it up with AC. Did I miss something?
You must know, I am a complete idiot when it comes to this stuff.
I can wire a shop but I don't understand motor windings or microwave transformers.


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## DangerZone (Jul 30, 2020)

I have an old microwave currently sitting in my shop on my workbench. I got it for free, and for the past year, its only purpose in life is re-heating coffee every so often when I get busy and it gets too cold.

It suddenly looks like I've got some more shop projects for this weekend!


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## ttabbal (Jul 30, 2020)

Janderso said:


> You guys seem to know what your talking about.
> Once I find a used microwave, I'll be consulting you guys.
> DC? He hooked it up with AC. Did I miss something?
> You must know, I am a complete idiot when it comes to this stuff.
> I can wire a shop but I don't understand motor windings or microwave transformers.




He used a small power supply, looked to be a 12VDC. You would want something current limited as your resistance is going to be pretty low.  He did connect that power supply to the AC main, but the coil looked to be on DC. I bet if you asked him, he would even send you a link to the PSU he used.


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## rwm (Jul 30, 2020)

I just reviewed. The power supply is 12V at 10 amps. I am not sure that would be enough current to hold down a piece of aluminum.
Robert


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## Boswell (Jul 30, 2020)

rwm said:


> hold down a piece of aluminum


I don't think there is enough current in the world to hold down aluminum :


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## DavidR8 (Jul 30, 2020)

That was extremely cool!


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## Janderso (Jul 30, 2020)

DangerZone said:


> I have an old microwave currently sitting in my shop on my workbench. I got it for free, and for the past year, its only purpose in life is re-heating coffee every so often when I get busy and it gets too cold.
> 
> It suddenly looks like I've got some more shop projects for this weekend!


Game on!!!


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## Winegrower (Jul 30, 2020)

Just note he used two microwave transformers for the chuck.


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## GunsOfNavarone (Jul 30, 2020)

We've been discussing a new microwave, now I know what to do with the old one! I had no idea..


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## Weldingrod1 (Jul 30, 2020)

A sneaky source of ready to go magnetic chucks is magnetic door locks...

On another tack, it is possible to make an electromagnet that grabs Aluminum; I built one. It's basically a shaded pole motor set up so the field travels inward radially. Buzzes, but holds Aluminum!

Sent from my SM-G892A using Tapatalk


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## rwm (Jul 30, 2020)

Induced currents in Aluminum don't count! A lot of stuff you would not think is magnetic actually is including people. Does aluminum have an unpaired spin?
On a more practical note; what was the epoxy resin he used to embed the magnets? 
Robert


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## Lo-Fi (Jul 31, 2020)

rwm said:


> Induced currents in Aluminum don't count! A lot of stuff you would not think is magnetic actually is including people. Does aluminum have an unpaired spin?
> On a more practical note; what was the epoxy resin he used to embed the magnets?
> Robert



Looked like "potting compound" as commonly used in the electronics industry. Cheap and readily available


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## nnam (Jul 31, 2020)

Here are couple screenshots I took:


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## middle.road (Jul 31, 2020)

Ah crap, I've got the old microwave sitting in the storage trailer/shed, and I just loaded up the old (running) dishwasher yesterday onto the scrap trailer to haul away.
'WANT_To-Do' just increased by two projects, - possibly.


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## pontiac428 (Jul 31, 2020)

1. What the hell, I'll watch this video.
2. This guy is innovative...
3.  I need a drill press mag chuck!


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## homebrewed (Jul 31, 2020)

As a side note, the commonly-available JB Weld has magnetic iron oxide as a filler.  You don't want to use it if you don't want a magnetic material in your application.  And using it to glue down super-magnets gets real interesting.  On the other hand, it might work to glue the pole pieces of your made-from-scratch electromagnet together.

Once you add in the cost of the magnet wire for a total DIY approach, it actually might be more cost effective to BUY a couple of MOTs (a commonly-used acronym) from Ebay, but, as has been mentioned, you'd want the old-school type with some real heft to them.  Microwaves that use a switching power supply won't work for this application.  And if you can get 'em for free....a no-brainer there....


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## ttabbal (Jul 31, 2020)

I never would have thought of using a mag chuck on a drill press, but now I kinda want one.


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## pontiac428 (Jul 31, 2020)

What was he babbling about the thing that needs to be discharged in the microwave?  Do I just stick my finger in there to drain the charge, or...?

I've got a line on one microwave already...


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## nnam (Jul 31, 2020)

I used to have a boat load of similar transformers from an auction of street lights.  I also had some large ones from a large 3 phase welder.  I ended giving them away.  I only kept one for making a spot welder, not very good for my result.

I now have 2 more microwave transformers to use.  
These are probably easy to find for cheap.


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## homebrewed (Jul 31, 2020)

"What was he babbling about the thing that needs to be discharged in the microwave? Do I just stick my finger in there to drain the charge, or...?"

He was referring to the high voltage power supply in the microwave.  A screwdriver (with an insulated handle) might work, depending on the HV capacitor.  Long-nosed pliers with insulated grips would work, too.

If the cap IS charged up, you might get a pretty good "bang" out of it.  Also, FYI, high voltage capacitors can RE-charge themselves if their terminals aren't shorted together, especially if they've been recently charged up.  To prevent potentially fatal shock, HV caps usually are shipped with shorting wires, as shown for this product.  If you buy some and they don't come that way, treat them like they were a rattlesnake.  Many Ebay vendors don't know s**t about what they're selling and this is a case where ignorance could result in a nasty surprise.


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## ttabbal (Jul 31, 2020)

It's a high voltage capacitor. Use something with an insulated handle to short the terminals. Those can hold a charge for a long time unplugged. Much like the old picture tube TVs. Do not touch anything in there until you do this. The charge is enough to be fatal if you get across it. One rule to follow is to keep one hand away from the device. That way, any charge you get on doesn't have a path through your heart. He's using needlenose pliers to short them. 

In reality, the danger is low if you treat it with a little respect. It's just not as obvious as a spinning lathe chuck that it can hurt you. In 90% of cases, there is a bleed resistor on those that discharges them over a few minutes, but those can fail. 

Ebay has the transformers, even new ones, for about $20. That said, old microwaves are probably available free most anywhere. Older is better. Some of the newer ones use a switching power supply and don't have these big cores to harvest.


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## pontiac428 (Jul 31, 2020)

Thanks, @homebrewed.  It's probably a good thing that I didn't have a lot of old microwaves laying around when I was a kid, or else I would have taken one apart like everything else and probably found out the hard way!


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## nnam (Jul 31, 2020)

I heard there is danger in the ceramic breaking if you get carried away and dissemble the magnet from the magnetron.   Not that I didn't do it  
Also, maybe it's a bit safer if it's more recent.


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## homebrewed (Jul 31, 2020)

pontiac428 said:


> Thanks, @homebrewed.  It's probably a good thing that I didn't have a lot of old microwaves laying around when I was a kid, or else I would have taken one apart like everything else and probably found out the hard way!


I DID discover this the hard way, playing around with an old tube-type TV.  Fortunately I wasn't bit too bad!


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## Janderso (Jul 31, 2020)

pontiac428 said:


> Thanks, @homebrewed.  It's probably a good thing that I didn't have a lot of old microwaves laying around when I was a kid, or else I would have taken one apart like everything else and probably found out the hard way!


You never want to pick up an automotive condenser (points and condenser) when sitting on the break room table. YEEOOWW!!
They bite.

I'm looking for a microwave. The drill press mag chuck makes all kinds of sense to me. Have wings on the frame to bolt to the t-slots in the table.


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## homebrewed (Jul 31, 2020)

Janderso said:


> You never want to pick up an automotive condenser (points and condenser) when sitting on the break room table. YEEOOWW!!
> They bite.
> 
> I'm looking for a microwave. The drill press mag chuck makes all kinds of sense to me. Have wings on the frame to bolt to the t-slots in the table.


Surely that condenser wasn't left there deliberately  .  And NO, I did not call you Shirley.  Time to go now...


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## brino (Jul 31, 2020)

rwm said:


> I just reviewed. The power supply is 12V at 10 amps.



Note too that in the video he wired the two coils in series:




So IF his coils were like mine (that I mentioned in post #14) and were around 1 ohm each.
He would have 12V across 2 ohms or about 6A thru the coils.
(His power supply could provide 10A, but he only was using 6A.)

-brino


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## GunsOfNavarone (Jul 31, 2020)

One thing I thought about watching this video... We work hard indication in out vises, I could see it being very easy for the top of this to not be parallel with the surface of your machine. How to get this totally flat/parallel... I'm not sure. Ideas anyone?


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## ErichKeane (Jul 31, 2020)

GunsOfNavarone said:


> One thing I thought about watching this video... We work hard indication in out vises, I could see it being very easy for the top of this to not be parallel with the surface of your machine. How to get this totally flat/parallel... I'm not sure. Ideas anyone?



What type of machine?  On a mill/surface grinder/shaper, you can bolt it down and grind/mill it in place.  On a drill-press you can mill/grind it flat, then have it be about as accurate as your drill-press table was anyway.


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## GunsOfNavarone (Jul 31, 2020)

Yeah, a surface grinder seems the way to go..if you're lucky enough to own one. This just seems to  good of a project to NOT do. I am about sure there are tons of free microwave on Craigslist. I wouldn't think it mattered if they worked or not, but bigger/better.


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## Janderso (Jul 31, 2020)

I would use it on my drill press.
I would agree, mill it and or use the surface grinder, take small cuts. Good enough for a drill press


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## rwm (Jul 31, 2020)

I would love to build one of these but I can't figure out what I would use it for? If I had a surface grinder yes! I don't think it would hold on a mill. 
Robert


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## matthewsx (Aug 1, 2020)

I don't have a mag chuck but I have been told it's wise to stand clear when you first start out since if it's not strong enough you can launch your workpiece pretty dramatically.

John


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## Janderso (Aug 1, 2020)

brino said:


> Note too that in the video he wired the two coils in series:
> 
> View attachment 332094
> 
> ...



brino,
I missed this,
This simple wiring would be hooked up to a DC power supply?
What would I look to purchase that would support this application?


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## SLK001 (Aug 1, 2020)

rwm said:


> It looks like he is using only the secondary windings? Does he say what voltage and amperage he is using thru these? Is it line voltage?
> Robert



In a MOT, the larger windings are the primary.  He discards the secondary.  He is driving it with 12V DC at 10 amps using a switching power supply.


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## SLK001 (Aug 1, 2020)

Another thing... He is going to regret not putting a proper strain relief on his power cord.  Once the cord becomes damaged (and it will with his configuration), he is either going to have to start over, or dig out the connections to remake them.

Also, I imagine that most people would abandon the project one-quarter of the way into the hand filing of the top!


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## rwm (Aug 1, 2020)

I may have had my windings backwards. since that is a step up transformer is the primary winding the winding with fewer turns and larger wire? The secondary winding is the finer wire? I suppose in theory transformers are reversible so it's really just a matter of semantics?
R


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## SLK001 (Aug 1, 2020)

rwm said:


> I may have had my windings backwards. since that is a step up transformer is the primary winding the winding with fewer turns and larger wire? The secondary winding is the finer wire? I suppose in theory transformers are reversible so it's really just a matter of semantics?
> R



Yes, the primary is the larger wire.

As for reversing the transformer, in theory your can, in practice you CAN NOT (has to do with the design).


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## nnam (Aug 1, 2020)

Use the larger wire.  The smaller wire is for higher voltage.  I imagine using the smaller wire, you can use home's electric without adapter.  However, the danger is electric shock if there is a break in wiring.  So stay safe, go for the larger wire and lower voltage.


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## HarryJM (Aug 1, 2020)

Janderso said:


> You never want to pick up an automotive condenser (points and condenser) when sitting on the break room table. YEEOOWW!!
> They bite.


Years ago (mid 70's) as a newbie motorcycle mechanic I learned very quickly to not catch a condenser that was tossed to me.


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## cathead (Mar 6, 2022)

I might make one as I have several old microwave ovens just waiting for something.  One could use
a battery charger to power it or even a switching mode power supply from a TV set.  It looks like a little
experimenting is in order.  There may be a down side in that the materials held down could easily end
up magnetized.


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## brino (Mar 6, 2022)

Janderso said:


> brino,
> I missed this,
> This simple wiring would be hooked up to a DC power supply?
> What would I look to purchase that would support this application?



Sorry Jeff I somehow missed this question from 2020!
I only found it in re-reading this thread today, because I linked to it from another post.

To answer your question, any 12V power supply that can provide around 10A of current should work.
User @nnam posted some frame-grabs of the one used in the video in this post:
https://www.hobby-machinist.com/thr...rom-the-guts-of-a-microwave.85743/post-764074
That one looks like a switching power supply.
There are many equivalent ones on amazon in the $10-$20 range.

I think what's confusing you is this:

Transformers only do their "normal job" of converting one voltage to another voltage when used with alternating current (AC).
They can either be:
step-down transformers where the output voltage is lower than the input voltage, or
step-up transformers where the output voltage is higher than the input voltage.
But again, they can only do this with AC.

Here we are using the step-up transformer from an old microwave oven.
In their normal use in the microwave oven they convert the 120VAC into a very high voltage needed by the magnetron.
Something like 1800-2500VAC.
That voltage gets half-wave rectified (one high-voltage diode) and then "smoothed" by a capacitor.
It is this capacitor that can have the high-voltage stored in it for many hours after operation.

okay....back to how we use it.......
However here we completely remove the high-voltage secondary winding.
This leaves us with a nice coil of wire around a laminated steel core.
It is no longer a transformer so we don't need to use AC.
We re-use this coil and core as an electromagnet with direct current.

Brian

For much more info look here:
http://repairfaq.org/sam/micfaq.htm#micsaf


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## wachuko (Mar 6, 2022)

Oh…now I also want to build one…


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## brino (Mar 6, 2022)

I find transformers fascinating..... the fact that we can convert electrical energy to magnetic energy and then back to electrical energy in itself is amazing. And then, the fact that in such a small volume we can reduce the voltage but increase the current; or conversely decrease the voltage and increase the current it's almost mind-blowing..........so forgive me if I'm a little excited!

It seems like it should take quantum physics and or some kind of black magic to understand or build one..... but it does NOT!
(at least at a level "good enough" to rewind existing transformers and even make your own.)

Thanks to my Dad, an electronics technologist and forever science-minded learner, for giving me a love of the same.
When I was in public school we would set aside time for him to teach me; ohm's law, capacitors, inductors, basic transistors, etc.
He also let me use his basement shop to build projects, rewind transformers, re-charge magnets, build a Jacob's ladder from a furnace transformer, try electroplating, etc. Luckily my Mom did not see all of it, or some of it would have been shut-down.



rwm said:


> I may have had my windings backwards. since that is a step up transformer is the primary winding the winding with fewer turns and larger wire? The secondary winding is the finer wire? I suppose in theory transformers are reversible so it's really just a matter of semantics?



With any transformer just remember that there is a certain number of volts per turn of wire.
The winding with the more turns has more volts, whether it is the input or the output.
(The winding with the larger diameter wire has more current.)

So in the case of a step-up transformer (that by definition has fewer volts on the input (primary) than the output (secondary)) there must be fewer turns on the primary winding than the secondary winding.
Just be aware that the volume of the windings is not enough to judge; the two windings can me made of very different gauge of wire. So the coil with fewer windings may actually look bigger!



SLK001 said:


> As for reversing the transformer, in theory your can, in practice you CAN NOT (has to do with the design).



Sure you can reverse it.
If you have a 120VAC to 12VAC step-down transformer, it is fine to "use it backwards".
You can supply 12VAC to the coil with fewer turns (was secondary, now primary) and generate 120VAC on the coil with more turns (was primary, now secondary).

*But* just understand a couple things:

Each winding was designed for a specific voltage and current. (affecting the number of turns and the wire gauge.)
You cannot take that same transformer and supply 120VAC on the coil with fewer turns and hope to get 1200VAC on the other side.
Even though it normally has a 10:1 when used "forwards" and 1:10 when used "backwards" there are limits! (to both directions).
In this case the limit is the current thru the coil based on the impedance of the coil.
Don't be scared off.... impedance is just the "AC resistance" of the coil. It is much like the DC resistance, and can be used in ohms law the same way as DC resistance, however the impedance depends on the frequency of the AC voltage.

In this example, if you have not changed the impedance (by changing either the coil inductance or the AC frequency) then by increasing the voltage from 12VAC to 120VAC you have increased the voltage by 10 times.

We know that Ohms law says: I = V/R
but for AC circuits with a coil(inductor) we replace R (resistance) by ZL (inductive impedance), and so get: I = V/ZL
If we increase V by ten times and leave ZL the same, then the current (I) has also increased by ten times.

Remember I said that each coil was designed for a specific voltage and current?
Well a ten times increase in them would very likely violate what that coil was designed for and burn up the winding (unless there was a very carefully sized fuse in the system).

Also, there is no free-lunch....and in fact there are taxes for playing......
All transformers have losses, there is DC resistance in the windings, stray magnetic fields that do not get coupled into the sceondary, there are Eddy current losses in the core (decreased by the laminations of the transformer core material), etc. So even the best transformer cannot supply 100% of the input power to the output.

I had better quit now, before I start with more equations and put people to sleep.....

Brian


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## Janderso (Mar 8, 2022)

brino said:


> I find transformers fascinating..... the fact that we can convert electrical energy to magnetic energy and then back to electrical energy in itself is amazing. And then, the fact that in such a small volume we can reduce the voltage but increase the current; or conversely decrease the voltage and increase the current it's almost mind-blowing..........so forgive me if I'm a little excited!
> 
> It seems like it should take quantum physics and or some kind of black magic to understand or build one..... but it does NOT!
> (at least at a level "good enough" to rewind existing transformers and even make your own.)
> ...


Thank you professor.
You sure do explain this subject well!
I had to go back to see what the subject matter was.
This diy magnetic chuck just moved up on my to do list


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## tq60 (Mar 8, 2022)

Suggestions for build.

For power connectio use a barrier strip or screw terminal strip with feed through posts or use good solid wire.

Mount strip to side of unit and wire up before potting.

Use solid wire larger than needed and crimp then solder.

After confirmed good ready to fill.

Before filling you need to have top flat.

Get a flat chunk of steel and with wax paper between steel and magnets oe places steel across top and apply power.

Magnets attach to steel, fill with potting compound and after fully cured one can skim cut with mill or sand paper on a glass plate.

Sent from my SM-G781V using Tapatalk


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## Mitch Alsup (Mar 8, 2022)

brino said:


> I find transformers fascinating..... the fact that we can convert electrical energy to magnetic energy and then back to electrical energy in itself is amazing.



Brino, for someone who obviously understand this stuff as well as you do;
It amazes me that you do not understand that there is no electrical energy, no magnetic energy, there is just Electro-Magnetic energy.
{you know Maxwell's equations circa 1890s}


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## WobblyHand (Mar 8, 2022)

Maxwell's Equations, differential form.  That's all there is to it!  More than you ever wanted to know at:








						Maxwell's equations - Wikipedia
					






					en.wikipedia.org


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## jwmelvin (Mar 8, 2022)

Mitch Alsup said:


> there is no electrical energy, no magnetic energy, there is just Electro-Magnetic energy.
> {you know Maxwell's equations circa 1890s}



I’ve always understood Maxwell’s equations to describe the effect that one has on the other, not to define them as one and the same. In the form of an electromagnetic wave, the energy is of a combined phenomenon. But what about energy stored in an electric field, like a capacitor. You call that electromagnetic energy?


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## Mitch Alsup (Mar 8, 2022)

jwmelvin said:


> I’ve always understood Maxwell’s equations to describe the effect that one has on the other, not to define them as one and the same. In the form of an electromagnetic wave, the energy is of a combined phenomenon. But what about energy stored in an electric field, like a capacitor. You call that electromagnetic energy?



The energy is stored as E stress in the dielectric of a capacitor (at zero M). But to use the energy you need the electric parts and the magnetic parts.
Similar for the inductor, energy is stored in the M field (at zero E), but to use it you have to convert it back to E and M.

For similar reasons, power does not flow through wires, but flows through the E and M fields surrounding the wire.


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## brino (Mar 8, 2022)

Mitch Alsup said:


> Brino, for someone who obviously understand this stuff as well as you do;
> It amazes me that you do not understand that there is no electrical energy, no magnetic energy, there is just Electro-Magnetic energy.
> {you know Maxwell's equations circa 1890s}



Hi Mitch,

No doubt Maxwell was smart!  

No, NOT this guy......


(sorry about that chief!) 


Although it has been more than thirty years since my EM and calculus classes, I am still comfortable with the concept of transverse electromagnetic waves..... although the calculus muscles have suffered extreme atrophy.

However:

It's a tough subject. If you have ever tried to explain all this to someone without a rampant interest, a wonderful imagination and a few hours with a white-board you might as well be speaking some ancient Neptuian dialect.

I believe that these advanced concepts (although proven correct and better understood by brains bigger than mine) can sometimes get in the way. However, there are "conceptual shortcuts" that can really help solidify the idea. I am willing to make some less than 100% perfect statements that get the idea across "good enough" for the concept to be understood and used. 

In fact, there are probably some of these "conceptual shortcuts" I use every day when they are sufficient for the purpose.
It's kinda like still using Newtonian physics even though Mr. Einstein's new-fangled ways have been proven more accurate.
For masses much less than the sun and speeds much less than that of light, Newton was close enough.

After all, this is an internet board on machining...... if someone is designing a better radio, iphone, satellite system, etc. then I expect them to do a little more research. 

Does lack of understanding Maxwell's equations stop anyone from making an electromagnetic chuck for their workshop? 
No way!

Honestly I have been re-winding transformers since long before I had ever heard of Maxwell or his equations.
Did my transformers work okay?
Absolutely, and some are still in use about 40 years later.

Thanks,
Brian


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