Pictures of Milgauss with Big Magnets

[cht]

Originally Posted by REDiesel

OK

The instrument in the picture is a 300mhz NMR - Nuclear Magnetic Resonance. It is used for the identification and characterization of molecules both chemical and biological. The 300mhz is the size of the magnet which equates to about 7 Tesla or 70000 Gauss. Way beyond the limits of these watches and the magnets get bigger. Now that full magnetic field is only really around the sample which in this case is a spinning narrow tube. The yellow line on the floor is a 5 gauss line - that's the strength of the field there - as you get closer it increases. If the instrument weren't an "ultra-shield" the 5 gauss line would be further back - 20 years ago it would have been in the next room and there would have been a magnetic field of a few hundred gauss where I'm standing - messing up my mechanical watch. These moden instruments use a second magnet to cancel out the field of the first.

MRI uses a similar concept to characterize anatomy. In this case the magnet spins as the sample er... patient cannot. These are in the 6-15 tesla range which I'm thinking is what the patient would be exposed to. Again 60000 - 150000 gauss is way beyond the capability of the watch so not appropriate for a patient to wear and really dangerous. A radiologist working around an MRI would potentially benefit from the shielding of a Milgauss. Anyone working with MRIs please chime in. Hospitals also go to great lengths to shield the magnetic fields MRI emit as they can interfere with instruments and devices such as ventilators and pacemakers.

These magnets are powerful and expensive starting in the 6 figure range and going up to several million. I've heard stories of keys and tools getting stuck to these magnets, and once stuck it's there for a long while as the cost to quench and restore a cryo-superconducting magnet is more than a Rolex. I have also read stories of hospital gurneys flying across the room into the MRI.

All that said I'm not really an expert on this as I'm more of an X-ray crystallographer, so you real experts please feel free to elaborate.

I am a neurologist and we use a 3.0T magnetom, you can get small things off the magnet with considerable effort.

Large things like a metal ER gurney rolled in or more commonly the night janitor waxing the floors who got too close with his polisher will require the magnet to be quenched.

I take off my watch before I head to the MRI suite, even if I had a milgauss, since it (1,000 gauss) comes up pretty short of a 30,000 gaussian field.


PS, nice pic and great to see a one in the "field" Pun INTENDED. :p

[cedargrove]

Originally Posted by aschneid

yep but different methods of resistance...my understanding is the aqua terra's components aren't susceptible to magnetic fields, whereas the milgauss uses a Faraday cage

The original Milgauss from the 1950s relied solely on a shield.

The current Milgauss (released in 2007) continues to use the shield, but also uses anti-magnetic components (i.e. balance spring, balance wheel, pallet fork).

The current resistance is likely higher than the decades old name suggests.

[DCheeta]

I love it! Great pics, but especially I love learning new things. This is an area that I know very little about (there are many such areas). Thanks, guys!

[milgauss2232]

Has anyone or rolex ever conducted a resistance test on the new milgauss?

[HogwldFLTR]

Sorry it's not a Milgauss on my wrist but regardless, here I am in my work environment. I hope this is close enough.

[sierra11b]

Originally Posted by milgauss2232

Has anyone or rolex ever conducted a resistance test on the new milgauss?

It would be interesing to see just how resistant its become.

[thomaspp]

Good stuff!

[AndyK]

Originally Posted by Daytona4130

Doesn't the Omega Aqua Terra -gauss- have more magnetic resistance than the Milgauss?

Yes. Omega does it by using materials in the movement that are amagnetic rather than "shielding" like the Milgauss. So it is really an apples to oranges comparison.

[Brads1967]

Isn`t the Milguass a stunning watch ?

I`ve always loved that watch