The Breitling Watch Source Forums

Is it possible that a solenoid housed with a steel safe door could magnetise a watch? Its run off 4xAA batteries so a 6v solenoid. Not massively strong by any means, but could this create a strong enough field?

I don't really know how strong the field has to be to magnetise a watch

At the risk of starting yet another heated debate.........

I think that it would be strong enough in and of itself because the hairspring is so delicate, but presumably the current is only passing (and therefore creating an electric field) when the door is opening or closing, not all the time. I also get confused over the whole electromagnetism vs. magnetism thing so someone like Ianthe Klutz is better to comment.

I'm also assuming that if the solenoid is inside a safe door is pretty well shielded so not sure how much of the magnetic field will make it outside.

I think that I would be looking for a different source if the watch is getting magnetised.

I think the inner steel skin on the door is approx 1.5mm thick, its not massively heavy as it doesn't need to withstand entry attempts. The solenoid really doesn't feel that powerfull, but its the only source of magnetism the watches could be near. Plus like you say its not energized for very long.

I've just had a couple of instances where a watch has gained approx 5 mins within 12 hours. Each instance has only been a one off and the watches have been fine since, so even more wierd

Can you think of any other explination for these one off events?

Magnetism doesn't tend to go away, so doubt it's that - and 5 minutes in 12 hours is not much for a magnetised watch. Was the mainspring particularly low at the time that it gained - it may be that the watch wasn't transmitting enough power to the balance decreasing the amplitude, increasing the frequency and therefore speeding up the watch. Not sure what else it could be as an occasional problem.

Thats good news then, at least it rules out the magnetism theory I really couldn't say how much the mainspring was wound, but hopefully that explains the problem. Odd that its just happened on that occasion. The watch hasn't gained even 1 second in 10 hours so far today.

Cheers for the info Roff

Just to add a little more to this....

Is the solenoid "fail open" or "fail closed"? Meaning, does the solenoid need to be powered to keep the safe closed or is it only energized to open the door? My guess would be the latter, in which case the exposure time to the magnetic field is minimal. If it were the other way around, I'd be more concerned.

The beauty of solenoids is that once the current is turned off, the electromagnetic fields dissipate very quickly.

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“The only reason for time is so that everything doesn't happen at once.” - Albert Einstein

Are you sure it's operated by a solenoid and not a small motor, the electronic door locks you can buy for your house use a small DC motor, I imagine your safe may be the same, a 6V solenoid powered by 4AA batteries probably won't generate enough force to operate the bolt.

At any rate as Ian says even it it is a solenoid, any magnetic field generated would only be present for the amount of time the solenoid was in operation then would disappear.

S

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Steel Fish (Blue Dial)

A solenoid? Why wouldn't they just put a motor...

I would be careful honestly. Magnetism affects watches if its strong enough. I would be wary of your safe solenoid (but i wouldn't worry about your cell magnetising your watch though ).

You can buy a small watch case that will protect the watch. Put the watch in it, and then in the safe. Thats what my old man does.

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Panerai PAM212 | Panerai Diver Strap
Panerai PAM111 | Black Croc Strap
Omega Planet Ocean | SS Bracelet
Rolex Submariner | SS Bracelet (Sold, Awaiting Funds)
Breitling Navitimer Olympus | Brown Croc Strap (Arriving)

Its deffinitely a small solenoid in there and not a motor, I've had it apart and taken some of the play out of the mechanism. It was only £40 so not great quality.

The solenoid is powered only when opening the safe, but does not pull the main door bolts back. The handle operates the door bolts and the solenoid stops the handle from being turned.

If there is any risk from the safe, I'll just store my watches in another hidden location. From previous hydraulic and pneumatic experience I know how strong solenoids can be, but this thing is 6v and very weak

Buy a proper watch safe or a good safe thats isolated from magnetism.

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Panerai PAM212 | Panerai Diver Strap
Panerai PAM111 | Black Croc Strap
Omega Planet Ocean | SS Bracelet
Rolex Submariner | SS Bracelet (Sold, Awaiting Funds)
Breitling Navitimer Olympus | Brown Croc Strap (Arriving)

As if by some weird coincidence, the safe stopped woring this morning. Keypad bit went nuts So back it went and I exchanged it for a better one with a finger print reader and motorised door bolts.

See how I go with this, but after what Roff said I doubt it was the previous safe anyway