23 Comments
Sep 25, 2023Liked by Jack Forster

Tempest requirements caused the government to be at least two hardware and software cycles behind. Never mind the building with all the network wiring running through clear tubes in an exposed ceiling. The good old days........

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Sep 25, 2023Liked by Jack Forster

Lost cause I’m afraid, “Faraday Cage” is a much catchier name than “Mu Metal Enclosure”.

You’ll have an easier time erasing “Submariner No Date” from watch parlance.

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author

My older son just read the story and said to me, "Forget it, Dad. It's Chinatown." 😀

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Defending the proper use of the petitio principii is a syntactical hill upon which I will gladly die, so at least you may be assured of having company thereon.

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And since we’re on the subject of pet peeves and pedantry, divers do not use “oxygen tanks” (unless for very shallow deco stops), nor does a helium release valve allow a watch to go deeper. We all have our things.

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author

Rage, rage against the dying of the light, Mr. Heaton 😀

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Sep 26, 2023Liked by Jack Forster

But can "begs the question" be used in the black hole? 😂

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I came here to say that Brits do not like to say ‘full of go’ at all. In all my years I never once heard it uttered and I have been around long enough to know my onions... which we do (like to say)

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author

I feel like I've heard the idiom in the context of Britspeak but as I get older things get vague, what about "know my onions"

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If someone says you know your onions, it means you are experienced in something or you know a lot about a particular subject

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Dictionary

Definitions from Oxford Languages · Learn more

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know one's onions

phrase of onion

INFORMAL

be very knowledgeable about something.

"Fred knows his onions about Social Credit"

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Sep 25, 2023Liked by Jack Forster

Fight the good fight! You're not alone shaking your fist at that cloud, although when it comes to trying to insist on precision in watch-related terminology I expect that a number of us will take a bold step backward to let you stand as our designated champion. I'm here with moral support and snacks if necessary.

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Sep 26, 2023Liked by Jack Forster

Jack, a wonderfully written and thought-provoking piece, as always.

Also, the timing of your article is kismet - I've been experiencing frequent magnetization of my Christopher Ward Dune Bronze watch.

Granted, I work at a cancer center and am in and out of linear accelerator vaults all day. But my Seiko turtle has never suffered under these same conditions. I was beginning to suspect the composition of the watch case was the culprit, but i hadn't gotten around to cracking open my dusty Physics textbooks just yet.

If I am interpreting your thesis correctly, the low relative magnetic permeability of the CW bronze case is allowing the magnetic fields to flow through the movement rather than through the case (hence my frequent need of the de-magnetizer).

Anyhoo, keep fighting the good fight, Jack!

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Sep 26, 2023Liked by Jack Forster

This reminds me of one of my favourite quotes from a case I learned in law school, in a seminal English case on the difference between a lease and a licence:

"The manufacture of a five pronged implement for manual digging results in a fork even if the manufacturer, unfamiliar with the English language, insists that he intended to make and has made a spade." -Templeman J., Street v Mountford 1985 HOL

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Sep 26, 2023Liked by Jack Forster

How about the difference between anti-magnetic watches and amagnetic watches, both terms are used interchangeably yet there’s a massive difference in the technology used.

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Sep 26, 2023Liked by Jack Forster

Another great reading Jack! Thank you for you eloquence.

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Sep 27, 2023Liked by Jack Forster

Gold is an wonderful conductor... Does a gold case provide some magnetic protection, like a Faraday Cage?

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author

That's an excellent question ... well, as you point out gold is indeed an excellent conductor so you could certainly make a Faraday cage out of it. As the article notes, though, a Faraday cage does not shield against magnetic fields (a compass will still work inside a Faraday enclosure). I don't think gold would shield against magnetic fields very well if at all – if it did, a gold-cased watch, to be antimagnetic, would not need any additional shielding (like a soft metal dial and inner case).

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Sep 28, 2023Liked by Jack Forster

If that sneaky peek at a magnet in your Instagram stories implies that you'll be following the antimagnetic / amagnetic interest thread (flux lines?) into some new practical testing of the resistance of current watches to magnetic mischief, I'm here for it – waiting with bated (not baited) breath, hoping you'll be a real trouper (not trooper) and do a whole bunch of scary experimentation including measurements of the effects of magnetic exposure on ticking and tocking!

I keep seeing watch brands making vague references to a silicon thingummy here, and a paramagnetic whatsit there – carrying implications of improved outcomes in the face of Magnetic Difficulties but with no real spelled-out guarantees (except from Omega).

How do current Rolex movements fare without the old Milgauss's shielding? Is everything a Milgauss now?

How about the newest JLC calibres?

Do IWC Ingenieurs with their fancy new movements still have the goods, whether or not they're shielded in the traditional way?

Are some of the brands bunging in some amagnetic bits while still leaving a few Achilles heel components in place, or are they doing full and effective end-to-end implementations of magnetism-ignoring movements?

Oh, and... what's up with quartz movements versus external magnetic fields? I've always been curious about those magnetically-shielded Grand Seiko quartz watches – is the magnetic shielding meant to reduce short-term timing impacts of magnetic fields on the watch, or to protect internal permanent magnets in the motors (is that a thing?) from permanent damage, or... ?

Oh, and since you're a stickler for precision in terminology... what's up with mixing and matching of units for magnetic field strength versus flux density as watch brands choose how to specify their watches' level of magnetic insouciance?

All I want is... it all. Thank you!

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author

Well, I see there is a follow up story in here and in the meantime I salute you as another standard bearer for precision in the use of the English language 😀 watch this space, as they say. Watches of Espionage asked me about magnets in compasses worn on a watch strap ... a deep dive seems in the works.

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Oct 4, 2023·edited Nov 1, 2023

Its not a Faraday Cage, but if we are trying to be accurate, it isnt Mu metal. Or if they are using a Mu metal shield, they are doing it wrong.

Mu metal has a high permeability but relatively low saturation compared to iron. This makes Mu metal a good shield for highly sensitive components against low fields.

Watches are relatively robust, and the magnetic fields they are shielding against are quite high.

A soft iron or steel is a better choice

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Oct 4, 2023·edited Nov 1, 2023

From Mu-Metal.com:

“Mu metal is used primarily in fields of low intensity because of their high attenuation characteristics. Soft iron finds application in fields of high intensity because of its high magnetic saturation characteristics”.

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As a teen I remember my father espousing the virtue of reading EVERYTHING a particular author wrote. For him, it was Hemingway- he had of course all the books, but also collections of Hemingway’s newspaper dispatches and letters.

I would enjoy a similar Jack Forster collection, watch related and not. Thanks for keeping it fun. It’s a great joy reading your playful phrasing.

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