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How important is an Antimagnetic timepiece?
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R3D9
路The good news is we may have ourselves a $500 demagnetizer... lol 馃槣
https://www.lepsi.ch/watch-demagnetizer/
馃
https://www.lepsi.ch/watch-demagnetizer/
馃
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R3D9
路Final post... not sure if they're a pay-for-an-article publication or not, but Watchtime has an article about the magnetizer:
http://www.watchtime.com/wristwatch...ogy/introducing-the-lepsi-watch-demagnetizer/
I'm cautiously optimistic. 馃嵖
http://www.watchtime.com/wristwatch...ogy/introducing-the-lepsi-watch-demagnetizer/
I'm cautiously optimistic. 馃嵖
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base615
路The good news is we may have ourselves a $500 demagnetizer... lol 馃槣
https://www.lepsi.ch/watch-demagnetizer/
馃
I think the 500CHF is including the watch scope. Hoping to try the demagnetiser out tonight so I wish I'd shelled out for the scope to give it a try too 馃榾
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Wryfox
路I just received my cheap internet demagnetizer to add to my watch tool box. $10US delivered from amazon(search watch demagnetizer).
Also added to the toolkit is the magnetism detectors (3 liquid filled 2" compasses for $5US delivered from ebay).
Both work great. I tried the demagnetizer by heavily magnetizing a large screwdriver tip. Followed the internet instructions on how to use (no instructions in box)....hold steady at surface of demagnetizer (you'll feel a strong vibration when close enough), then slowly pull up and away over 3 seconds. Three tries and screwdriver was perfectly neutral. This is far worse than dealing with a magnetized watch so it showed it has decent power to do the job.
As for the compass at detecting magnetism, they worked great. The points will move significantly when a watch is magnetized. Of course there are levels of magnetized, so most watches did nothing (good), a couple wiggled the points just a few degrees, and a couple moved the points substantially (90 degrees or more). Vast majority of my watches are purchased in person but the ONLY ones magnetized were those I purchased online and had shipped to me, specifically the international purchases. This suggest there is something in the transportation process (likely MRI security screening) that is mildly magnetizing the watches.
I'll report more later on the effect on accuracy from demagnetizing.
Her are pics...(crappy cell phone camera for expediency)
Also added to the toolkit is the magnetism detectors (3 liquid filled 2" compasses for $5US delivered from ebay).
Both work great. I tried the demagnetizer by heavily magnetizing a large screwdriver tip. Followed the internet instructions on how to use (no instructions in box)....hold steady at surface of demagnetizer (you'll feel a strong vibration when close enough), then slowly pull up and away over 3 seconds. Three tries and screwdriver was perfectly neutral. This is far worse than dealing with a magnetized watch so it showed it has decent power to do the job.
As for the compass at detecting magnetism, they worked great. The points will move significantly when a watch is magnetized. Of course there are levels of magnetized, so most watches did nothing (good), a couple wiggled the points just a few degrees, and a couple moved the points substantially (90 degrees or more). Vast majority of my watches are purchased in person but the ONLY ones magnetized were those I purchased online and had shipped to me, specifically the international purchases. This suggest there is something in the transportation process (likely MRI security screening) that is mildly magnetizing the watches.
I'll report more later on the effect on accuracy from demagnetizing.
Her are pics...(crappy cell phone camera for expediency)
Edited:
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Tony C.
路路惟f Jury memberMany metals do not offer any magnetic isolation: stainless steel, aluminum, etc. are totally transparent to magnetic fields. Faraday cages offer electromagnetic isolation (emi, microwave, etc) but not magnetic. For magnetic isolation, one needs soft steel (not stainless), mu-metal, etc. enclosure.
Michel
Do you mean soft iron, Michel?
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Wryfox
路I wanted to update my post from a couple months ago, with an actual example to use. I have an old Bulova Masonic watch that was my grandfathers. I was checking all my watches for magnetism after getting the compass and demagnetizer above. This one in particular made the compass points move fully around the dial, being by far the worst of any others.
Of 40 mechanical watches tested, about 1/2 made no affect on the compass, the rest made slight movements, from 10 to 20 degrees or so. I would not consider those "magnetized" though they may be slightly affected, their performance is just fine. Two others moved the compass points about 40 degrees or so. They also run well so I'll leave them alone as well. I don't really know what the gauge of "magnetized" is except where it relates to performance.
So, the Bulova had starting specs of +73s/d accuracy, and 248 deg amplitude. Not running well to start so lets see what happens after the demagnetizer is used. NOTE: there are videos on the internet showing to place the watch directly on the demagnetizer and then pull straight up over several seconds. This seems to be the predominant way to do this, BUT, it did NOT work for me. I tried it this way twice and found the watch had improved but was still significantly magnetized. My process was to move the watch back and forth laterally across the demagnetizer surface and then in circles for about 5 seconds then slowly pull away for a couple seconds until it is about 6 inches off the surface. This removed all magnetism and did not affect the compass points at all after that.
Pre specs: +73s/d, 248 amplitude
Post specs: +23s/d, 295 amplitude
Opened the back and further slight regulation got to virtually perfect accuracy in face up position. Can't be more delighted that this demagnetizer worked perfectly for demagnetizing a watch.
Nice looking movement for 41 years old....a very std sort of movement from what I've found. Not crap but not exceptional either. A very Bulova type of movement I guess you could say.
Of 40 mechanical watches tested, about 1/2 made no affect on the compass, the rest made slight movements, from 10 to 20 degrees or so. I would not consider those "magnetized" though they may be slightly affected, their performance is just fine. Two others moved the compass points about 40 degrees or so. They also run well so I'll leave them alone as well. I don't really know what the gauge of "magnetized" is except where it relates to performance.
So, the Bulova had starting specs of +73s/d accuracy, and 248 deg amplitude. Not running well to start so lets see what happens after the demagnetizer is used. NOTE: there are videos on the internet showing to place the watch directly on the demagnetizer and then pull straight up over several seconds. This seems to be the predominant way to do this, BUT, it did NOT work for me. I tried it this way twice and found the watch had improved but was still significantly magnetized. My process was to move the watch back and forth laterally across the demagnetizer surface and then in circles for about 5 seconds then slowly pull away for a couple seconds until it is about 6 inches off the surface. This removed all magnetism and did not affect the compass points at all after that.
Pre specs: +73s/d, 248 amplitude
Post specs: +23s/d, 295 amplitude
Opened the back and further slight regulation got to virtually perfect accuracy in face up position. Can't be more delighted that this demagnetizer worked perfectly for demagnetizing a watch.
Nice looking movement for 41 years old....a very std sort of movement from what I've found. Not crap but not exceptional either. A very Bulova type of movement I guess you could say.
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Archer
路路Omega Qualified WatchmakerFYI - lift angle for that Bulova is 51 degrees.
Just for those who might not be familiar, to simplify/explain what a demagnetizer is doing, think of the ferrous materials inside the watch has being made up of tiny dipoles. One end is positive, and one negative. If the poles of all these are aligned in one direction (all positive point to the left say), then the item is "magnetized". If the poles are randomly aligned, then they "cancel each other out" and the item doesn't show any magnetic effect.
So the demagnetizer can be of 2 types. One has a constant strength magnetic field and the other has a field that decays over time. Both of these use AC, so imagine the field generated by the demag is swinging back and forth on each cycle, and taking the poles of all the little dipoles in the watch with it.
The constant field type require that you move the watch away from the field (can be a plate or a circular coil) and the idea is that as you slowly move the watch away, those little dipoles will stop alternating bit by bit and end up in more or less random patterns, removing the magnetism in the watch. This is why the instructions will tell you to move the item away from the field slowly. If you place an item on/in one of these, press the button, hold it there, and release the button without moving the part or watch away, you can actually magnetize the item instead of demagnetizing it.
The instantaneous type, which is what I use, will discharge a capacitor when the button is pressed, and the strength of the alternating field will decay on it's own, so there's no need to move the watch around. You just place the item on the demag and press the button:
Cheers, Al
Just for those who might not be familiar, to simplify/explain what a demagnetizer is doing, think of the ferrous materials inside the watch has being made up of tiny dipoles. One end is positive, and one negative. If the poles of all these are aligned in one direction (all positive point to the left say), then the item is "magnetized". If the poles are randomly aligned, then they "cancel each other out" and the item doesn't show any magnetic effect.
So the demagnetizer can be of 2 types. One has a constant strength magnetic field and the other has a field that decays over time. Both of these use AC, so imagine the field generated by the demag is swinging back and forth on each cycle, and taking the poles of all the little dipoles in the watch with it.
The constant field type require that you move the watch away from the field (can be a plate or a circular coil) and the idea is that as you slowly move the watch away, those little dipoles will stop alternating bit by bit and end up in more or less random patterns, removing the magnetism in the watch. This is why the instructions will tell you to move the item away from the field slowly. If you place an item on/in one of these, press the button, hold it there, and release the button without moving the part or watch away, you can actually magnetize the item instead of demagnetizing it.
The instantaneous type, which is what I use, will discharge a capacitor when the button is pressed, and the strength of the alternating field will decay on it's own, so there's no need to move the watch around. You just place the item on the demag and press the button:
Cheers, Al
