How can demagnetising a watch mess up rate and beat rate?

[Boydie]

I mistakenly demagnetised a watch that was running (I read today you shouldn’t do this, correct?). And then it’s rate went to about -600s/d and it’s beat rate went to 4m/s, event to the point the timegrapher couldn’t read it.

now I can’t fix the issue.

any advice greatly appreciated.

 

cheers,

Boyd

[watchweasol]

I should recheck the watch for magnetism with a compass, sounds like you have inadvertantly magnetised it and its affecting the balance spring coils, take the back off and have a look at the coils when working  are they concentric and beating evenly and also flat.. Post pictures or a video of ithe movement.

[mikepilk]

I've always demagnetised running watches with no problems.

Check that the hairspring hasn't popped out from between the regulator pins.

[JohnR725]

11 hours ago, mikepilk said:

I've always demagnetised running watches with no problems.

Check that the hairspring hasn't popped out from between the regulator pins.

Over the years I've had people tell me and I've seen it in print that it is very bad to Demagnetize A running watch yet I do it all the time with no problems except? The second part of the quota unfortunately applies make sure the hairspring is still between the regulator pins or make sure it's not caught on the regulator pins.

Or the basics look at your hairspring does it look right?

[Boydie]

10 hours ago, JohnR725 said:

Over the years I've had people tell me and I've seen it in print that it is very bad to Demagnetize A running watch yet I do it all the time with no problems except? The second part of the quota unfortunately applies make sure the hairspring is still between the regulator pins or make sure it's not caught on the regulator pins.

Or the basics look at your hairspring does it look right?

Thanks John!

[Boydie]

21 hours ago, mikepilk said:

I've always demagnetised running watches with no problems.

Check that the hairspring hasn't popped out from between the regulator pins.

Many thanks Mike, I’ll check!

[Paul80]

Hi.

Given my minimal understanding of these things so take the following with a large pinch of salt, but given that a magnetised watch generally runs fast not slow, I wonder if someone in the past tried to slow down a fast running magnetised watch, then when the OP demagnetiser it, it would naturally suddenly run slow.

Obviously I may be talking out the back of my hat but it's a thought

 

[JohnR725]

10 minutes ago, Paul80 said:

Given my minimal understanding of these things so take the following with a large pinch of salt, but given that a magnetised watch generally runs fast not slow, I wonder if someone in the past tried to slow down a fast running magnetised watch, then when the OP demagnetiser it, it would naturally suddenly run slow.

Theoretically you are actually correct. Oftentimes you'll see the regulator and watches pushed to the extreme to make up for a problem or perceived problem of timekeeping. Use of the problem is the watch desperately needs to be serviced. Conceivably a heavily magnetized watch could cause the same thing to happen.

On 4/10/2022 at 1:09 PM, Boydie said:

I mistakenly demagnetised a watch that was running (I read today you shouldn’t do this, correct?). And then it’s rate went to about -600s/d and it’s beat rate went to 4m/s, event to the point the timegrapher couldn’t read it.

now I can’t fix the issue.

On discussions like this where things aren't going in the direction they should be now is the time where additional questions are needed. Like the running watch what was it doing how well was keeping time. Then the usual one was the last time the watch was serviced and it would be nice to know what watch it is.

Also timing machine pictures it be nice to see a picture of the timing machine. Often times we may see or understand something that's not obvious to someone new to the use of the timing machine.