5Kw or 30KW?

[ChrisOlson]

Damned if I know, I never write stuff down, I'll have to check it again.

Yeah.  Do the spin test again @ 100 rpm with a rectifier on it.  I'm pretty sure it should've been around 30-35 volts @ 100 rpm.  A set of 12 foot GOE222 blades likes to run at 380 at the top end.  So whatever you get at 100 rpm times 3.8 will be the open DC voltage at the right rpm for them blades.
--
Chris

[fabricator]

Yep it's 30.5 volts at 100 rpms so that's 115.9 open volts

[ChrisOlson]

Yep it's 30.5 volts at 100 rpms so that's 115.9 open volts

Yep.  That's what I thought.  Is that AC volts, or DC with the rectifier on it?
--
Chris

[Mary B]

Hey I like towers! But I have a ham radio license and am biased, a big antenna shining up in the air...

[Frank S]

Just when you get something in your mind and plan on waiting for 5 months before buying magnets something comes along that you just can't pass up today searching around in a scrap yard I found this.

 So I asked the guy if he had any more. YEP he said half a box full of them.
 How much for them I asked
 $20.00 each  How many do you have and how much for all of them
 I don't know 40 or 50 maybe and$15 if you take all but 2 of them
 I said OK if less than 50 I'll give $15.00 apiece for them over 50 up to 75 $12.00 over 75 $10.00
 Darn there are less than 50 OH well win some loose some
 then I brought a couple back to my shop He is going to box the rest up for me
 I couldn't wait to see if what was inside would turn out to be what I thought it would.
  Sure enough 4 bright shiny 2"x2"x1" blocks since these are mil surplus I imagine at least neo 42 I know the 4 magnet assembly will lift about 500 lbs or more.
 So now I have over 160 magnets to play with

[fabricator]

Be gentle with em they shatter easy and the nickle will scrape off with your fingernail.

[fabricator]

Yep it's 30.5 volts at 100 rpms so that's 115.9 open volts

Yep.  That's what I thought.  Is that AC volts, or DC with the rectifier on it?
--
Chris

Rectified DC.

[midwoud1]

Lucky man in Kuwait.
You can make 6 windturbines of it.
What is the best idea to remove the magnets from the steel plate?
Mill, Lathe ,Heat just to melt the glue, Grind

- Frans -

[fabricator]

Ther're probably just stuck in place, couple screwdrivers and a hammer ought to do the job, Frank be VERY careful with these mags they are extremely dangerous.

[Frank S]

 I will X that bridge when I come to it.
   Tomorrow when I pick the rest of them up I will see what sort of container the guy came up with.
 Each assembly has a pipe handle about 6 inches long if I didn't need the handles to help separate them I would cut them off to make a smaller package but if you get 2 of these things stuck face to face you could forget getting them apart.
 when I carried them into the shop they were face to face  I told the guys that if any one of them could get them apart I would give that guy tomorrow off It was lots of fun watching 50 guys take turns using up their entire lunch hour trying to pull those things apart. Finally my sides were hurting too much from laughing so I laid them on the floor and stood on the handles they still held firm so I jumped down on them will all the force I could develop with my 200 lbs it was just barely enough to open up a gap of about 30 degrees I quickly dropped a piece of 1/2" plywood in the opening. Even at that they couldn't pull them apart. It took another piece before the fields were far enough apart for them to separate the assemblies.
 One of the guys said Strong is the force in these Apart pull them we could not only the master separate them could he .
  I looked around to see if I could find Yoda   

[Frank S]

 Fab thanks; I've handled these before all be it much smaller ones.
 I don't know what these things cost but it is a lot more than  I paid for them

[ChrisOlson]

Sure enough 4 bright shiny 2"x2"x1" blocks since these are mil surplus I imagine at least neo 42 I know the 4 magnet assembly will lift about 500 lbs or more.

Are you sure them are neo?  They look like the same 2 x 2 x 1" thick ferrite blocks that I use in my wind turbines.  They're pretty powerful if that's what they are - you get two of 'em stuck together and you got some issues.

Neos can be drilled with a regular cobalt drill.  Ferrites are so hard that unless you got a diamond drill you won't even make a mark in one.  That's one way to check to see what they are.
--
Chris

[Frank S]

Sure enough 4 bright shiny 2"x2"x1" blocks since these are mil surplus I imagine at least neo 42 I know the 4 magnet assembly will lift about 500 lbs or more.

Are you sure them are neo?  They look like the same 2 x 2 x 1" thick ferrite blocks that I use in my wind turbines.  They're pretty powerful if that's what they are - you get two of 'em stuck together and you got some issues.

Neos can be drilled with a regular cobalt drill.  Ferrites are so hard that unless you got a diamond drill you won't even make a mark in one.  That's one way to check to see what they are.
--
Chris

Thanks Chris. I was wondering how to really check them.
 If they are ferrites I didn't get as good of a deal but come what may I've got at least 160 blocks that I would not otherwise bought until much later.
 If they are drill-able would you just drill a single hole in the center and countersink it or risk creating a stress fracture by drilling 2 or 3?
 I would think that a single 6 or 8 mm counter sunk hole just as a positive locator . That is assuming of course these blocks are drill=able 

[ChrisOlson]

If they are drill-able would you just drill a single hole in the center and countersink it or risk creating a stress fracture by drilling 2 or 3?

There was a guy from Ireland here that drilled his neo magnets for pins once.  The trouble with this is that neo magnets usually have a thin nickel coating and once that is compromised air and water gets to the magnetic material and causes it to rapidly deteriorate.  Neo magnets are very fragile and if you accidentally shatter one you'll actually get lightning in the air between the pieces when it explodes**.

Ferrite magnets are harder than the hubs of hell and the only thing known to man that will machine one is liquid cooled diamond tools.  And the machining is always done before the magnet is magnetized.  If those are ferrite magnets you don't have to worry about drilling holes in them because it's not going to happen.

**If those are neo magnets, like fabricator said, be really careful with them because they are more dangerous than a M60 machine gun with a stuck trigger and a full belt.  If they're glued and you try to get them off you run a high risk of having one shatter and explode.  And when they do there will be a bright flash and pieces that are as sharp as razor blades head towards anything made of steel at velocities exceeding the speed of light.  That might not seem possible, but it's never been proven to not be possible because anybody that has had one explode is usually injured and just knows it to be fact without any scientific explanation.

Make sure your eyeballs are protected, you're wearing gloves and depending on how much you care about holes in your face you may want to have that covered too.
--
Chris

[Frank S]

 Having run lathes & mills grinders and welding most of my life I'm pretty good about the eye /face and hand protection, but that is some of the best advice, and analogy of their capability I've heard anyone publish.
 I'm not so sure about the lightening flash actually emitting from the shattered pieces but I wont dispute that either, because I did shatter a very small one once a  couple years ago trying to pry it out of its mounting. I'm pretty sure the flash was associated with the particles striking my face shield as they returned to normal space. But that could have been because the face shield also had wire mesh.
   

[ChrisOlson]

When I've busted them the flash I've seen appears to be between the particles of the magnet itself.  It's a brilliant bright white flash and I'm not sure what causes it.  My theory is that it could be a warp in the space-time continuum caused by the re-arranging of magnetic stuff and you're momentarily looking into a different dimension.  I may have discovered the secret to time travel and don't even know it   
--
Chris

[CraigM]

I have a stack of 6" x 2" x 1" Ferrite mags at home and although difficult they can be twisted apart and restacked without great difficulty. The only neo's I have are 1/2" x 1/2" x 2" and these have "mo' power capt'n" then the ferrites.

If what you have are indeed 1" thick neo's I think a simple test with a small piece of angle iron would tell the story. Can't imagine you would be able to pull a piece of iron off one of them or even safely get anything magnetic close to them without it getting ripped from your hands.

[Frank S]

When I've busted them the flash I've seen appears to be between the particles of the magnet itself.  It's a brilliant bright white flash and I'm not sure what causes it.  My theory is that it could be a warp in the space-time continuum caused by the re-arranging of magnetic stuff and you're momentarily looking into a different dimension.  I may have discovered the secret to time travel and don't even know it   
--
Chris

OR maybe how to actually build a warp drive engine
 Seriously though for everyone who might read this there are numerous cases where people have been seriously injured accidently with the NEOs exploding.  The way they are made in the first place if it were done back in Medieval times it would have been called nothing less than wizardry. I can't say the flashes that I saw happened at the magnet or when the particles struck the mesh of my face shield so Chris  you may be on to something and we just don't know it yet let me know if you think we should set up a test lab

[ChrisOlson]

If what you have are indeed 1" thick neo's I think a simple test with a small piece of angle iron would tell the story. Can't imagine you would be able to pull a piece of iron off one of them or even safely get anything magnetic close to them without it getting ripped from your hands.

Neo magnetic lifters usually have a handle on them that shuts off the magnets in the lifter so it can be gotten off a piece of steel.  I'm not sure how it works, but I assume it slides a heavy plate of steel in between the magnets and the work piece and the heavy piece of steel shunts the magnetic lines of force, cancelling it.
--
Chris

[Frank S]

I just opened one of the pieces up again and the magnets are only held in place by their own. I noticed one of them had shifted from its original position. SO after a lot of careful prodding and prying I managed to slide one off the plate then managed to get too close to my mill good thing I had gloves on or it would have taken the hide off of a finger. I removed another one and it tried to spin in my hands from about a foot away. I got a good grip on it and tried to force it near the one on the mill I couldn't force it closer than 3 inches without it trying to wrench itself from my grip.
  What ever they are they are plenty strong
 I wouldn't want 2 of them to slam together 

[fabricator]

I have a pretty decent pile of neo shards, one of em I took out of my palm with forceps like you see em pullin out bullets in western movies, a mere mortal would have passed out.

[ChrisOlson]

  What ever they are they are plenty strong

They sound like neos to have that sort of range.  Can you tell if they have a nickel coating?
--
Chris

[ChrisOlson]

I have a pretty decent pile of neo shards, one of em I took out of my palm with forceps like you see em pullin out bullets in western movies, a mere mortal would have passed out.

This is how you stack 'em together for storage without damaging them

--
Chris

[fabricator]

Cool way to do it, I usually use welding gloves and have lots of bandages and iodine handy and my dremmel with a small bit to drill through purple fingernails, Oooooh that feels good when that blood shoots out and relieves the pressure.
Then sooner or later you come to the point where you have two discs with 40 or so of the SOBs on em.

[Frank S]

I'm still not sure if they are neos. Just not taking any unnecessary chances with them.
 When I first removed the sheet metal cover from the assembly and saw that they were shiny silvery in color my first impression was neo. Most magnets I have delt with in the past few years were stepper motor or automotive starter motor shaped field magnets. and those things although some have been much larger than these had nowhere near the strength  these have and were always non coated  black natural colored.
 in one of the convoys while driving up in Iraq a few years ago there was something along side the road that could have been an IED our convoy was stopped and  held up for half an hour while it was removed. It turned out to be nothing more than someones lost lunch box cooler that had a lots of duct tape on it holding it together probably from a previous convoy but in 2004 they didn't take chances. So why should I at this stage in the game
 I might try to drill into one. Like Chris explained to me neos can be drilled with a good cobalt bit
  and ferites cannot.
   The closer I get to 60 the more I realize that I'm not 20 and indestructible any more   

[Frank S]

OK Chris what would you think Neo or not Neo that is the question
 I didn't have a cobalt bit laying around just  the HSS so I thought I'd give it a go just to see if it were even possible to mark the silly thing with a hand drill and pretty good down pressure I managed to dimple the surface rather quickly it was like the the tip of the drill was on fire with the sparks not using any coolant I'd have expected no less. Stupid me  I let go the magnet with my boots before getting the drill away from it and it jumped from the board to the drill then clamped itself on the chuck. pulling that thing off the chuck was like trying to land a 9 lb black bass with a Zebco  202 

[fabricator]

They're neos, have you ever known the military to go cheap when state of the art is available? Tie a string around one so it will hang straight, hang it away from any metal, if it just hangs there turn it 180 if it swings back with that face pointing north pretty fast it's a neo and that face is south, ferrites do the same thing but they swing slower.

[ChrisOlson]

High Speed Steel won't drill a neo.  But from your description of the strongness of the magnets I think they are neo.  They could be samarium cobalt too, which is the next strongness down from neo.

I suppose the only way to know for sure is to test them with a gauss meter.
--
Chris

[Frank S]

 Chris if this helps there is no color change from the surface to the inside of the dimple
I'm beginning to suspect they could be early lower grade neo.
 the assembly can be placed on a vertical H beam and a person can almost stand on the handle.

Fab I can lay one in my hand on one of its edges if I face it one way it will spin in my palm on its own  no string needed. I let a hack saw blade stick to one and nearly bent it double trying to remove it

[Frank S]

 it really doesn't matter I have them and no matter what they are made of they're worth more than I had to pay for them Be it $5.00 or $100.00

[ChrisOlson]

A drill bit would've chipped the nickel coating on a neo.  Neos are either coated with nickel (very thin and fragile layer) or epoxy of some sort.  The neo magnetic material cannot be left exposed to air so they will always have a coating.

Ferrites have a shiny surface but it is not bright like nickel and they are a little darker in color.  Samarium cobalt sort of looks like ferrite but it's stronger magnetic strength than ferrite.

Like I said before, those big ferrite blocks that size are not weak either.  When assembling rotors with them they still make things move on the bench and scoot around and stick to things.  Even neos will not spin around in your hand and align themselves to the earth's poles because the earth's magnetic field is not that strong.  It would have to be hung from a string, so I don't know what's up with that.

The only way to know for sure is get out the gauss meter and check them at the surface of the magnet.
--
Chris

[Frank S]

Chris  Iwas too close to the shelf unit in my small home work shop it has heavy angle iron supports behind it  my glove was slick  when the magnet tried to turn I must have moved my hand just far enough away to keep it from jumping out of my hand so later  I got to thinking about it so  Idid like Fab suggested and tied a string around it so it hung like a diamond from one edge keeping the wide sides vertical, it turned pretty quickly so  I shifted the string around so it hung with one of the small sides up It spun around better Of course not having an actual string handy I used an ear bud similar to those I pod things the bud was stuck to one of the big sides if I held it just right when released it would spin around sometimes going past enough to make another full turn then rotate back and forth in diminishing swings for a while . Not like hanging an old Iron bar magnet by any means this thing was quick and kind of funny 

[ChrisOlson]

Yeah, even the big ferrite blocks will do that sort of stuff though.  You can't force two of them 2 x 2 x 1 C5 Grade ferrite closer to another one than about 3".  And if you have N-S on those they'll smash your fingers as good as a neo.

So the only way to tell is to test them.  You should get 1.1-1.2 T at the surface of the mag if it's a N42 and 250-300 mT if it's a ferrite.  If it's somewhere in between those two it's either a weaker grade of neo or a samarium cobalt magnet.  But a weaker grade neo still should be above 900 mT.

The magnetic field strength in the air gap of that direct drive turbine I built was 621 mT when I tested it with my gauss meter, with N42 2 x 1 x .5 bars.  With the 2 x 2 x 1 ferrite blocks at the same 20mm air gap it's only about 170 mT.  You need to know that anyway to build a generator from scratch with those magnets unless you want to make a WAG on what to wind it with.
--
Chris