Are gold watches less susceptible to magnetism?
Discussion
Finally got off my backside to try a simple experiment. I have two old style mechanical watches, both Omega as it happens and neither of chronomter quality. Anyway, wound them up and put both side by side into a sealed steel container to ensure no outside magnetic influence. Measured their accuracy over half an hour using the stop watch on my phone. Then repeated the same exercise after putting a strong magnet inside the box - it was in fact the magnet from a speaker. Repeated the exercise twice both with and without the magnet.
I should add that one watch is stainless steel whilst the other is a gold seamaster
To my surprise, the magnet did affect timekeeping causing both watches to gain at the rate of about 6 seconds per hour compared to what they did when there wasnt a magnet present. The gold case of the seamaster made no difference whatsoever - the gain was the same for both watches. Not really surprisng since the magnetic effect of austenitic stainless and gold are similar
Yes the experiment was a bit crude and could be significantly refined. But I did spend my university years in the physics lab so I am confident that the results are worth some consideration.
I should add that one watch is stainless steel whilst the other is a gold seamaster
To my surprise, the magnet did affect timekeeping causing both watches to gain at the rate of about 6 seconds per hour compared to what they did when there wasnt a magnet present. The gold case of the seamaster made no difference whatsoever - the gain was the same for both watches. Not really surprisng since the magnetic effect of austenitic stainless and gold are similar
Yes the experiment was a bit crude and could be significantly refined. But I did spend my university years in the physics lab so I am confident that the results are worth some consideration.
bordseye said:
Finally got off my backside to try a simple experiment. I have two old style mechanical watches, both Omega as it happens and neither of chronomter quality. Anyway, wound them up and put both side by side into a sealed steel container to ensure no outside magnetic influence. Measured their accuracy over half an hour using the stop watch on my phone. Then repeated the same exercise after putting a strong magnet inside the box - it was in fact the magnet from a speaker. Repeated the exercise twice both with and without the magnet.
I should add that one watch is stainless steel whilst the other is a gold seamaster
To my surprise, the magnet did affect timekeeping causing both watches to gain at the rate of about 6 seconds per hour compared to what they did when there wasnt a magnet present. The gold case of the seamaster made no difference whatsoever - the gain was the same for both watches. Not really surprisng since the magnetic effect of austenitic stainless and gold are similar
Yes the experiment was a bit crude and could be significantly refined. But I did spend my university years in the physics lab so I am confident that the results are worth some consideration.
If I am understanding you correctly, the experiment didn't demonstrate whether your watches are magnetised. What you demonstrated was that your watches perform differently in the presence of a strong magnet.I should add that one watch is stainless steel whilst the other is a gold seamaster
To my surprise, the magnet did affect timekeeping causing both watches to gain at the rate of about 6 seconds per hour compared to what they did when there wasnt a magnet present. The gold case of the seamaster made no difference whatsoever - the gain was the same for both watches. Not really surprisng since the magnetic effect of austenitic stainless and gold are similar
Yes the experiment was a bit crude and could be significantly refined. But I did spend my university years in the physics lab so I am confident that the results are worth some consideration.
Get a compass. Wait for the needle to settle. Move your watch close to the glass of the compass. Does the needle move noticeably?
If it does, your watch is magnetised and probably not working optimally. (No, the compass test isn't perfect but a noticeably deflecting needle is generally a sign of magnetism).
Zio Di Roma said:
If I am understanding you correctly, the experiment didn't demonstrate whether your watches are magnetised. What you demonstrated was that your watches perform differently in the presence of a strong magnet.
Get a compass. Wait for the needle to settle. Move your watch close to the glass of the compass. Does the needle move noticeably?
If it does, your watch is magnetised and probably not working optimally. (No, the compass test isn't perfect but a noticeably deflecting needle is generally a sign of magnetism).
It did demonstrate that the watches werent magnetised in that the experiment went no magnet /magnet / no magnet /magnet and after removal of the magnet the watches kept time as well as they did before the experiment. And the magnet used was way stronger than the field that would be created by the tiny current flows in a keyboard. Get a compass. Wait for the needle to settle. Move your watch close to the glass of the compass. Does the needle move noticeably?
If it does, your watch is magnetised and probably not working optimally. (No, the compass test isn't perfect but a noticeably deflecting needle is generally a sign of magnetism).
Your compass test is a perfectly valid one. So I put the compass on the desk and lined up the pointer with the scale. I then moved my keyboard back and foward from maybe 20cm away to 1 cm away and rotated it and watched the needle for deflection. There was none perceptible. It is a wireless keyboard - the result might be different if yours is wired.
So my conclusions would be that gold casing doesnt protect any more than austenitic stainless steel, that strong magnetic fields do surprisingly affect an old fashioned mechanical watch, that there is no remnant magnetism in the watches and that the field if any from a keyboard is irrelevant,
I am puzzled why the field affected timing since the huge majority of the components in the watch are rotary. Anyway, thanks for bringing the subject up - it was an interesting little experiment. Quite took me back to my time in the labs decades ago.
bordseye said:
It did demonstrate that the watches werent magnetised in that the experiment went no magnet /magnet / no magnet /magnet and after removal of the magnet the watches kept time as well as they did before the experiment.
They could still be magnetised though. The fact that they kept time as well as they did pre-exposure doesn't make them not magnetised. As I have mentioned, I have a Rolex Sub that runs better magnetised.
My watches all seem to have a "peak magnetism" beyond which they don't become more magnetised, too,
Zio Di Roma said:
They could still be magnetised though. The fact that they kept time as well as they did pre-exposure doesn't make them not magnetised. As I have mentioned, I have a Rolex Sub that runs better magnetised.
It leaves me fairly curious as to what there is inside mechanical watches that is made of iron or steel. I imagined that everything would be brass or gold, both of which are non magnetic. Any ideas?
Zio Di Roma said:
My watches all seem to have a "peak magnetism" beyond which they don't become more magnetised, too,
That would be true.Anyway, at the end of all this I am happy that a gold case, at least one From Omega, doesnt protect a watch for the effects of a strong magnet.
Edited by bordseye on Sunday 3rd October 17:19
bordseye said:
Zio Di Roma said:
They could still be magnetised though. The fact that they kept time as well as they did pre-exposure doesn't make them not magnetised. As I have mentioned, I have a Rolex Sub that runs better magnetised.
It leaves me fairly curious as to what there is inside mechanical watches that is made of iron or steel. I imagined that everything would be brass or gold, both of which are non magnetic. Any ideas?
Zio Di Roma said:
My watches all seem to have a "peak magnetism" beyond which they don't become more magnetised, too,
That would be true.Anyway, at the end of all this I am happy that a gold case, at least one From Omega, doesnt protect a watch for the effects of a strong magnet.
Edited by bordseye on Sunday 3rd October 17:19
Zio Di Roma][url said:
This has arrived. Much beefier than the Chinese demag tool.
Demagnetises in a second with a beep.
|https://thumbsnap.com/vYtj9qMQ[/url]
This is quite good actually.Demagnetises in a second with a beep.
|https://thumbsnap.com/vYtj9qMQ[/url]The Chinese demag tools can be a bit of a faff, with repeated attempts required to demag a watch.
The new one seems more effective. Usually no more than two goes to demag a watch.
Cant help but think you have got a bit of a "bee in the bonnet" about this! ;-) A really strong magnet caused little in the way of error on the watches that I tried. Yes it caused some error but it was small and the magnetic field I used was far more than you would get in casual use unless you worked in a hospital near the scanners or similar.
If greater accuracy is required then the answer is electronics rather than mechanical. You will never get something with moving metal parts to give you the same accuracy as electronics will.
If greater accuracy is required then the answer is electronics rather than mechanical. You will never get something with moving metal parts to give you the same accuracy as electronics will.
bordseye said:
Cant help but think you have got a bit of a "bee in the bonnet" about this! ;-) A really strong magnet caused little in the way of error on the watches that I tried. Yes it caused some error but it was small and the magnetic field I used was far more than you would get in casual use unless you worked in a hospital near the scanners or similar.
If greater accuracy is required then the answer is electronics rather than mechanical. You will never get something with moving metal parts to give you the same accuracy as electronics will.
More of a hornet actually.If greater accuracy is required then the answer is electronics rather than mechanical. You will never get something with moving metal parts to give you the same accuracy as electronics will.
Your test was, if I am being honest, largely meaningless. The presence of a strong magnet and its impact upon the performance of a watch is not the point in the context of our discussion. It is retained magnetism that matters.
The makers of quality mechanical watches go to great lengths to make their watches accurate. Well not all makers to be fair, but many. Magnetism defeats their best efforts. Many of them use their accuracy as a marketing tool. COSC certified JLC’s 1000 hours etc.
As I have previously mentioned, my JLC Master Control is incredibly accurate when not magnetised, but not when it is magnetised.
With regard to a non-mechanical watch being the solution. In terms of timekeeping you are probably correct. However, if you have a love of mechanical watches, as I do, it sort of defeats the object.
Many people, you included apparently, don’t care about the accuracy of mechanical watches. Perhaps I shouldn’t, but I do. In a world so full of magnets perhaps I am like some sort of horological King Canute.
Zio Di Roma said:
Which components get magnetised? According to Loomes watchmakers, who I spoke to about this, it's the hair spring. I believe the winder stem plus other components will also be steel and hence susceptible.
Anything ferrous can become magnetised but yeah, from a timekeeping POV, it's the hairspring that matters most.Since you mention fine watches such as your JLC, they will be (potentially) more vulnerable to magnetism if they have small balances with fine hairsprings and have curb pin regulators instead of being free sprung. (Edit- by which I mean they will be more vulnerable to timekeeping errors due to becomeing magnetised)
A chunky Rolex with a free sprung overcoil can still have its timekeeping affected by magnetism, but if its coils are spread out farther (because it's larger) and there are no curb pins to regulate the watch then there is less physical interference than, say, an ultra-thin watch with a fine flat hairspring.
In the latter case, as the magnetised coils tend to pull towards each other, the hairspring can spend more time resting against one curb pin and less time in the middle. Since curb pins average-out the length of a hairspring to create an "effective" length, interfering with this will interfere with how far the balance travels in a given direction.
If the hairspring is especially fine or the watch is badly magnetised, the coils themselves can actually touch which not only completely wrecks the time keeping, but will have an affect on the beat error, interfering with the ability of the watch to self-start when low on power.
So all of the above is not really an issue of gold vs steel cases (although gold is not ferrous at all and so likely no use whatsoever), but rather an issue of making really fine watches vs big agricultural ones, and obviously the materials used in the in the watch.
Materials which are great for isochronosm and temperature may not be great for magnetism and vice-versa, perhaps most famously in the niobium-zirconium hairspring of the ill-fated Ingenieur 500,000 A/m which was almost totally impervious to magnetism but which was just terrible at isochronism and temperature to the point where IWC gave up on it.
Edouard Guilluame won a Nobel prize for his invention/discovery of two nickel-iron alloys, one which expanded very little with common temperatures (making it great for balances) and one whose modulus of elasticity changed very little with temperatures (great for hairsprings). These were total game-changers back in the day as temperature compensation was a total nightmare from a watch regulation POV (and why high grade pieces are regulated for temperature and not just position), but now we take it for granted and watches are expected to live with temperature changes.
Silicon hairsprings appear to be what many are betting their futures on now as the material is very resistant (completely immune?) to magnetism, although brittle compared to metals.
Edited by glazbagun on Sunday 10th October 21:43
glazbagun said:
Zio Di Roma said:
Which components get magnetised? According to Loomes watchmakers, who I spoke to about this, it's the hair spring. I believe the winder stem plus other components will also be steel and hence susceptible.
Anything ferrous can become magnetised but yeah, from a timekeeping POV, it's the hairspring that matters most.Since you mention fine watches such as your JLC, they will be (potentially) more vulnerable to magnetism if they have small balances with fine hairsprings and have curb pin regulators instead of being free sprung. (Edit- by which I mean they will be more vulnerable to timekeeping errors due to becomeing magnetised)
A chunky Rolex with a free sprung overcoil can still have its timekeeping affected by magnetism, but if its coils are spread out farther (because it's larger) and there are no curb pins to regulate the watch then there is less physical interference than, say, an ultra-thin watch with a fine flat hairspring.
In the latter case, as the magnetised coils tend to pull towards each other, the hairspring can spend more time resting against one curb pin and less time in the middle. Since curb pins average-out the length of a hairspring to create an "effective" length, interfering with this will interfere with how far the balance travels in a given direction.
If the hairspring is especially fine or the watch is badly magnetised, the coils themselves can actually touch which not only completely wrecks the time keeping, but will have an affect on the beat error, interfering with the ability of the watch to self-start when low on power.
So all of the above is not really an issue of gold vs steel cases (although gold is not ferrous at all and so likely no use whatsoever), but rather an issue of making really fine watches vs big agricultural ones, and obviously the materials used in the in the watch.
Materials which are great for isochronosm and temperature may not be great for magnetism and vice-versa, perhaps most famously in the niobium-zirconium hairspring of the ill-fated Ingenieur 500,000 A/m which was almost totally impervious to magnetism but which was just terrible at isochronism and temperature to the point where IWC gave up on it.
Edouard Guilluame won a Nobel prize for his invention/discovery of two nickel-iron alloys, one which expanded very little with common temperatures (making it great for balances) and one whose modulus of elasticity changed very little with temperatures (great for hairsprings). These were total game-changers back in the day as temperature compensation was a total nightmare from a watch regulation POV (and why high grade pieces are regulated for temperature and not just position), but now we take it for granted and watches are expected to live with temperature changes.
Silicon hairsprings appear to be what many are betting their futures on now as the material is very resistant (completely immune?) to magnetism, although brittle compared to metals.
Edited by glazbagun on Sunday 10th October 21:43
Sounds like I am going to have to live with magnetism and poor timekeeping, if I am going to wear fine dress watches.
Gassing Station | Watches | Top of Page | What's New | My Stuff