Safety warning?!!! ;)

A bit of humor:

1.5" supermagnet : safety sheet
http://www.houseofscience.com/ouch/ouch.html




Know of any other good "safety sheets?"

Aha! http://www.dumb.com/productwarnings.htm


(((((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))))))
William J. Beaty SCIENCE HOBBYIST website
http://amasci.com
EE/programmer/sci-exhibits amateur science, hobby projects, sci fair
Seattle, WA 206-789-0775 unusual phenomena, tesla coils, weird sci

 

Why would one fabricate a rare earth dipole magnet as sphere? It's a
great price for the big one! The obvious thing to do is to order two
and see how the pair is shipped. Kinda hard to envision a "keeper" to
lessen field decay/time.

We as a culture deserve to be destroyed. It would be an act of
compassion.

 

because its easier than fabricating a monopole magnet as a sphere?

 

The 1.4 megagauss number is absurd; kilogauss, maybe. I seriously
doubt the part about separating the iron out from one's blood, too;
superconductive MRI magnets are far more powerful than any PM can ever
be, and have no such problems. And no small magnet is going to affect
a color TV from three feet away.

This guy sounds like a fathead, hardly a humorist.

John

 

They're also farther away. Inverse cube law, right? But anyway, if I
remember correctly (which I might not), the magnetic field in MRI is pulsed,
and is pretty even throughout the cavity, meaning that it shouldn't pull
things strongly in any particular direction. By contrast, I believe Kevin's
talking about being within a centimeter of the magnet for a prolonged period
of time. Obviously, he handles the things himself.

I shop at his store pretty regularly. There's probably not much point in my
vouching for him since you don't know me either, but for what it's worth,
you might want to at least have a conversation with him before labeling him
as a fathead. In my experience he's not one, at least no more so than most
of us.

 

A megagauss is 50 teslas. No way in Hell - not even for a two-stage
supercon magnet plus a conventional core. The only two ways to get in
the megagauss region are to either push a whole huge laser capacitor
bank through a metal loop, flashing it to plasma in the process; or
cool a pre-stressed armored conventional magnet with a river of high
pressure water and push a DC powerplant through it (Ritter magnet, but
not for long).

The force of magnetic attraction depends on field divergence. Trace
the field lines of a dipole sphere - wow! It would be a great
micro-gee experiment for International Space Station Freedom FUBAR
Space Hole One Alpha. You float two spheres with facing opposing
poles a fair distance apart and ready your triggered high speed
camera. They will smash together almost explosively (hopefully
killing everybody aboard with shrapnel and letting the huge stupid
expensive worthless nightmare deorbit to its welcome destrucuton).

Uncle Al has a pair of fair-sized Fe-Nd-B magnets, with a book in
between. You handle those puppies with great respect and keep the far
away from computers and TVs. Even a Helmholtz pair of ceramic ferrite
magnets from a microwave oven are dangerous if you get your flesh in
the way when they kiss. NEVER allow a pair of magnets like that to
freely slam together.

It would be intesting for Oxford Magnets to try hydroponically growing
seeds in the bore of one of their really high field supercons during
required shakedown. Photosynthesis is all about charge, hence triplet
spin, segregation. Twenty teslas on a well-chosen flower would be the
cat's pajamas: "Consider the lilies of the field, how they grow; they
toil not, neither do they spin!"

 

The patient is *inside* the magnet. Can't get closer than that.

The gradient fields are pulsed, but they're fairly small. The main Z0
field is a huge DC superconductive magnet.

Well, part of your body is outside the field, and part is right in the
strongest part. That's a hell of a gradient.

The way you get a blood clot from supermagnets is by letting a pair of
them snap and pinch you. *That* can really hurt.

John

 

As it happens, yes.

A halfhour ago I was using the lamp used for spectroscopy. On the
housing for the lamp, it says with the standard DANGER sign: Do not
touch leads while on.

Thanks for the tip, PASCO. *chuckle*

 

[snip]

Make that "Bitter magnet," and then to only 37 teslas.

http://www.hfml.kun.nl/20t-magnet.html
http://www.mext.go.jp/english/news/1999/10/s991002.htm

Uncle Al is sweating the chirality of a Klein bottle's non-orientable
surface. It's slow going.

 

Know of any other good "safety sheets?"

I have a bottle of Children's cold medicine that states that one shouldn't
operate any heavy machinery after taking a dose...

 

I thought megagauss fields had been made with copper coils pulsed to
exorbitant currents for milliseconds; is that a Bitter? Something
about using flywheels and special low-impedance DC generators to
provide the pulse current. I'll have to look it up.

Oh, I just hung a cluster of supermagnets on a string, off the edge of
my desk. The detent action in the Earth's mag field is very
impressive. If you bring things near it, the deflection of the string
indicates attraction: $20 bills, some inks, a big old rubber drafting
eraser, stuff like that show small effects. But I saw no sign of
attraction to my own flesh; the iron in blood is apparently not
magnetic.

So I stand by my "fathead" assessment.

Agreed on the space station: a useless, boring, leaky, smelly waste of
a good hunk of a trillion dollars.

John

 

http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=1000000+gauss+in+tesla&btnG=Google+Search


John

 

A pet peeve of mine: Everytime I order a pack of carbide inserts for my
milling machine I get an MSDS warning about eating or enhaling them.
Now I can see how they might cause some damage if you cram one up your
nose but it says nothing about mangling your fingers or flying metal
chips putting out eyes.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

 

IIRC, it's because the shape of the sphere compresses the field.
So you get a very intense field at the poles, but more ordinary
field strength away from the poles.
Socks

 

Well, some of those are pretty dumb, but some are actually the
result of translations out of English to some other language,
then back. For example, the warning not to use the hairdryer
while sleeping should be not to use it on somebody who is
sleeping or otherwise unable to communicate the fact that they
are being burnt. Such as hospital patients still under the
drugs and so on. See, if you are not conscious, you can't
tell anybody your head is too damn hot.

There's other warnings that sound stupid but are the result of
such translations. For example, persons who are unable to roll
over on their own, should not use waterbeds. If they wind up
on the heater and touching bottom, they could be there slowly
getting cooked and not able to get off the heater. So the
warning on my waterbed that I should not use it while sleeping
is amazingly dumb on its face, but really means I should not
be placed in it if I'm unconscious due to drugs, injury, medical
condition, etc., but normal sleep is fine.

Just remember, all your warning is belong to us.
Socks

 

My sister's barbecue grill has a warning something like "Watch
children closely while burning."

--Jeff

--
A man, a plan, a cat, a canal - Panama!

Ho, ho, ho, hee, hee, hee
and a couple of ha, ha, has;
That's how we pass the day away,
in the merry old land of Oz.

 

Yeah, one of those days. I'm battling Green's function for crystal
lattices, too. Both surviving neurons are chuggng flat out (if you
remember the 60s you weren't there). The rest of today is flying on
impulse engines.

 

A uniformly magnetized sphere has the field of a pure dipole.

 

On a Swedish chainsaw, "Do not attempt to stop chain with your hands or
genitals."

 

Do not look into laser beam with remaining eye.
-will-