Sorry for this being non-tech, but i couldn't think of anywhere else to post this, and you guys here are pretty smart about this stuff.

I am making an electromagnet, and i need some Soft Iron.. But i don't know where to get some.. I need a bar of Soft iron about half an inch in diameter and at least about 8 inches long. I went to Home Depot, and they had aluminum and Galvanized Steel.. (i know steel is iron with carbon added, but i want 100% soft iron.) what exactly is Galvanized Steel? Home Depot also had "plain" rolled steel. Where is the best place to get Soft Iron? Besides railroad spikes, which i think are probably now steel.. Thanks guys..!!

 

Look in your phone book for a local place under steel supply or welding places. If they have it laying around, a piece that big they'll give ya for free to a buck or 2.

 

What are you making the magnet for? Just curious.

 

just bored.... .. me and my friends have been playing with electricity latley, and a couple of ideas have popped into our heads, Tesla coil, super powerful electromagnets, rail guns, and stuff like that. whenever i get my electromagnet coil made, im gonna try and turn it into a ignition coil, and shock people, if its powerfull enough.. who knows..

 

I have a ringer out of an old telephone that will light you up when you spin it. If I remember correctly it puts out around 55 volts AC. You can also use a large transformer to step up the voltage of a battery to shock people Have fun

 

Ahh geez, what is this? This is going to be locked soon.

Well to set this guy straight, the voltage you get from a phone, is not through the phone itself, its through the wire that comes from the phone company's hub. While the phone is ringing you will get 54VAC or so, not that big a deal, but enough to let you know. Now a phone line not ringing will give you voltage, but only 9VAC or so. AND, a transformer will not "step up" the voltage, it just transforms it into a different type of current, hence the name "transformer".

Just wanted to chime in. Please dont shock anyone, thats dangerous.

 

Where did you study electronics? A transformer has a primary side and a secondary side consisting of windings. If there's twice as many windings on the secondary side, then you have double the voltage of the primary side, with 1/2 the current. Most home electronics, like VCR's and such work on 12 volts, and use transformers to drop the voltage. Line voltage at the pole is dropped from thousands of volts to 120/240 and so on. An ignition coil (which is a transformer) takes 12 volts and steps it up to the KiloVolt range. A transformers sole purpose is to step up or down voltage.

 

stngklr, I am a telephone technician, and am correct about what I said. If you read the post I said I took the ringer out of an old telephone. The old phone systems had no ringing voltage coming from the central office. The handle you turn on the side of the telephone would send 50 to 100 volts ac, depending on the model to the switchboard operater, who would then connect you to the person you wished to call. Also, most new phone systems send about 100 volts to your phone when it rings, but it is low amperage AC, which will hurt, but is harmless. And the regular line voltage on normal phone lines is 50volts DC, Although some different systems have as much as 130volts DC. Also, a transformer can step voltage up or down, depending on the windings and direction of flow through it. That is why electric companies require you to have a positive lockout system on your main breakerbox if you use a generator in case of power failure. Many linemen have been killed because of people backfeeding their 110volt generators through their transformers and putting voltage on a line that should be dead. I'm not flaming, but get your facts straight before you try to correct someone.

 

I wasn't flaming, but you did say transformers don't step up voltage, then you say they do in your reply. As far as correcting that goes, perhaps you just worded it wrong and I misunderstood what you said. Please re-read what I wrote and correct me if that's so. BTW I do have a degree in electrical engineering, and have worked with 14KV transformers in RF generators for years. I still don't understand what you are trying to get across with the phone line thing.

 

ZAsmpch, I agree completly with your post, I was replying to stngklr. He is the one who said that transformers don't step up voltage. Also I understand that you weren't flaming, just trying to get the facts correct. That's all I was doing with the phone line thing also. It irritates me to see people telling things they don't know to be true as fact, :nono: but that's enough ranting and raving for one night. How did you like the class in electrical engineering? I have taken a course on fundamental electronics and was thinking about taking that too. Electricity has alway's interested me. Later.

 

hey, you "electrical Engineers" and other smart electrical people.. Where did you guys start off at? Iv always been interested in electricity, and i would like to go further then what we learn in pyshics in high school, but not sure what kind of classes to take it college, what kind of things did yall start out with?

 

Breathment, If your college doesn't have any good classes that interest you, you could always try something like a correspondance course. You don't have a teacher, but you can learn at your own pace and just study what interests you. I had to do one by a company called Heathkit and it was pretty good. Most of the stuff was well explained and it came with a board you could use to wire up circuts to see how things work. I don't know how much it costed though, since the company paid for it. If you just have a passing interest in these things you can buy many books on the subject and most library's have good stuff to. Good Luck.

 

Have you guys ever heared of "cranking" it is a style of fishing were you have two boats going up a river and one guy is cranking one of those old style crankup phones he puts leads from the phone into the water and the guys in the boats behind his use nets to scoop up the fish. The electrical shock well for a better lack of words puts the fish in a state of shock and float up to the surface. You can pull a ton of fish that way but if the game wardens in Texas catch you they will take your phone and fine you big time................................

Isn't it interesting the things you can learn arround these rednecks in north east texas.

 

<------- Hoses himself off after being lit up.

Well I've been an Alarm Tech. for about 6 yrs. now, and know a little about electronics, but not quite as much as you guys I guess. I was thinking more along the lines of rinky dink transformers, ie. cellphone chargers, doorbells, transformers used to power alarm systems, etc... And all of these "step down" voltage and not "step up". I wasnt really thinking big. I guess I need to think more before I flame, I usually never do that, and feel horrible about it now. Stupid evil twin, too much alcohol.

The back feeding thing with the generators didnt even occur to me, but I've heard of it before and makes total sense now.

So I guess I just took a course in how to make yourself an @$$,
and passed with flying colors.

To all of you, my apologies. It will never happen again.

 

This post makes more sense now that I re-read it A good way to learn the fundamentals of electronics is to go to Radio Shack and get these books they have. They look like phamplets (sp?) and cover all the basic concepts of different types of electronics using very inexpensive components. Then if you find you like it, there's a lot of colleges that offer degrees in electronics, from the 2 year level on up. It's a good carreer choice, just don'd get into the IC manufacturing business like I did

 

Don't sweat it stngklr, we all make mistakes from time to time. Say, have any of you actually seen the cranking for fish thing work? I tried it myself(in a private pond of course,hehe)and couldn't get anything to happen. At first I thought I didn't have enough juice, because mine only puts out around 55 volts, but then I thought about lightening hitting water. If that killed fish you would never see a fish in a lake. Any ideas? I do have another crank style ringer that is much larger that I think will put out around 100 to 110 volts, but it has no crank on it and I can't get my cordless drill over the shaft. How long do you think this post will stay open if someone knows the exact procedure for giving the fish a shocking experience? Later

 

well, to get back on topic, well a little on topic anyways.. does anyone else know of a place where i can get some soft iron? like a website or something?? thanks

 

The best places I can think of are welders or machine shops. How strong are you trying to make it? I'm thinking of making one myself for use in a boat. You would be suprised at what you can find at the bottom of a lake. I found a 9 horse engine once, when a lake around here was drained for cleaning. It didn't take much to get it running although from the mud on the outside of it you never would have it would run.

 

Ground-start or Loop-start? Typically, I've seen 70-85VDC ringer signal depending on the distance from the switch. It can still bite!

And if you have an old magneto from a crank-signal telephone, your voltage should peak a LOT higher than 100V. If you catch it with an o'scope, your might see instantaneous peaks of over 400V. Them things is healthy little *******!

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Breathe,

As for the soft iron blank for a core, check with your local metals supplier as Jester suggested. If you don't have one of those nearby, you can mail order through American Science and Surplus (yes, A.S.S. is their acronym, and they laugh about it too).

Or, you could order a 2" round x 1' long ductile iron bar from McMaster/Carr (www.mcmaster.com) for about $21.00 per foot (their part number 89105K27 - $21.14)

Or you could just settle for a low carbon steel bolt. 1010 and 1018 steel typically have a very little percentage of carbon, and even less manganese, chrome, molebdynum, nickel, and other trace minerals. They're as close to regular old iron as you'll get for a bargain price. If you really want the metallurgy, check with Ede.

If you're really on a shoestring, you could just gut out an old small dry transformer or solenoid for the soft iron laminations. They're very effective at concentrating magnetic lines of flux. Elctricity is cool she-ot, but it will let you know almost instantly if you screw up. And once you let the smoke out of the spaghetti, it's hard to get it all back in.

If you want to have some serious fun with electrons, get your hands on a used-but-working neon sign transformer and a couple of uncoated brazing rods, and make a Jacob's Ladder. Stick a piece of banana or gob peanut butter on the upper ends of the rods and wait for houseflies...

And, in case you were wondering, no, this isn't ThirdGen "tech" specifically, but it is definietly "tech". Any time someone can learn about electricity it can be beneficial in a lot of fields, ThirdGen 'F' cars included. How many times have we seen problems that have a basis in or involve the electrical system (including engine control)? At least 25% of the posts, maybe? Then again, I'm biased toward that field somewhat. This post is certainly more "tech" than the "Did you see the Camaro on eBay?" posts.

Incidentally, I started off in the womb. I was sharing the "apartment" with some other pr#ck... I'm glad my lease there finally ran out.

 

Hey vader, our systems are all loop start, I didn't even know that the old ground start types were still in use anywhere. Our ringing voltage is around 100 to 110 volts low amperage AC, and will make you let it go for sure, but our regular line voltage(not ringing), is 48 to 50VDC. Most of the time you can't even feel it unless you are kneeling down on wet ground. I have two magnetos out of old ringers, but I could only measure the voltage on the very small one. I just guessed at the voltage of the larger one based on its size and number of magnets. I had no idea that some of them could peak at up to 400 volts. I guess I need to get it out and find a way to turn it and see what it's got . By the way, for that Jacob's Ladder, would the thing out of a floursent light (I forget what you call it) work? The Jacob's Ladder is the thing where you get an arc going up and down between the two rods, right?

 

as strong as i can possibly get, i want to build a prototype one, and then spend half of my summer building the biggest one i can possibly build, i just have to find a huge spool of magnet wire..

 

If you are going really big with it, you might do some research on the ones they put on some cranes. I've seen them picking up cars and other things, but never paid any attention to their design. Let us know how it turns out.

 

Yes, that is a Jacob's Ladder. A fluorescent light ballast is really more of a choke (reactor) than a transformer. The rapid-start ballasts do have transformer windings to generate the filament voltage for the preheat filaaments in the ends of the lamps, but that is typically less than 6V. The overall end-to-end lamp voltage is only the line voltage that is current-limited by the reactance of the choke. Once an arc is established in the mercury inside the lamp, the RMS voltage can actually get quite low to maintain the rated lamp wattage (current-limited by the reactance again).

To get a good Jacob's Ladder rolling, you need at least 6KV to start a plasma arc at the base of the rods. Once you have a nice little plasma ball rolling up the rods, the voltage determines how far and how fast the plasma (and arc) will travel. A 9KV neon sign transformer and a couple of 2' bare brazing rods makes for a nice little show, and doesn't do the flies any good either.

And yes, it's scary, but I've seen some older PBX systems that still use ground start analog lines. I think they may still be a little more common in older public systems on the east coast as well, but I'm not sure. I'm not that "up" on it.

 

We use dynomite here in Iowa...:lala:

 

instead of the neon sign transformer.. could i use an ignition coil? i know it wont put out as much voltaqe... but maybe easier to find and cheaper?

 

Dynomite is good too but is too loud

 

So a Jacob's Ladder would be something like this?:


Oh boy. Transformers are cheap too. Most of em are about $20 on ebay As if I really needed one more thing to get in trouble with...

 

My Grandpa used to charge condencers with a aparkplug wire. Then he would ask me to hold it....when I touched the end...SNAP!!