Escapement meter

[VWatchie]

On 10/14/2024 at 6:22 AM, JohnR725 said:

if this is true I do watch companies not publish numbers as opposed to minimum and maximum?

As an enthusiast, I have limited access to official documentation. Still, from what I've observed in the documents shared by @JohnR725 and others (Thank you!!!) from some major manufacturers, such as Omega and Rolex, I never saw any documentation stating the 270° magic number for amplitude at full wind in the horizontal positions. Hence I don't pay much attention to the 270° idea.

In these documents amplitude is typically given as a minimum in some vertical positions after 24h (often 200°) and as a maximum in the horizontal positions at full wind (usually around 300°). Trying to achieve these numbers has kept my sanity intact and I have been a much happier enthusiast ever since.

Just seeing the number 270 makes me feel slightly depressed as it almost made me give up on this wonderful hobby before I knew better.

20 hours ago, nickelsilver said:

I had a nice little Piaget 9P in last week, which hit 255 or so horizontal. However, it only dropped to 240 in vertical, and had a 15 second delta over 6 positions, going to 20s at 24h and amplitude staying above 200. So I let it go at that.

I think this quote says most of it!

[praezis]

I see the problem that you don‘t have any immediate reference how well your movement is doing. < 300 is trivial. Else you will have to wait for 24 h after each measure?

2 hours ago, VWatchie said:

In these documents amplitude is typically given as a minimum in some vertical positions after 24h (often 200°) and as a maximum in the horizontal positions at full wind (usually around 300°).

[Klassiker]

2 hours ago, VWatchie said:

As an enthusiast, I have limited access to official documentation

Same here, but I don't really need it. The values in those documents are specifications; instructions within that organisation, defining hard and fast targets which the service centres have to achieve. They are by definition company- and movement-specific (although inevitably generic to a large degree).

What we are talking about here is a rule of thumb, an indicative value which gives you some useful initial information about the "health" of the movement. In isolation it is practically worthless, and it isn't a target in itself, but if you aren't seeing it, then you it should give you pause for thought.

2 hours ago, VWatchie said:

In these documents amplitude is typically given as a minimum in some vertical positions after 24h (often 200°) and as a maximum in the horizontal positions at full wind (usually around 300°). Trying to achieve these numbers has kept my sanity intact and I have been a much happier enthusiast ever since.

I'm struggling to understand why you can happily work to these values as targets, but not accept 270 degrees as a reference point or initial indicator. Essentially, they are bound together and dependent on one-another. Usually, the vertical positions will have lower amplitude than the horizontal ones. The difference will usually be at least 20 degrees but could be as much as 50 degrees. After 24 hours the amplitude will also have fallen, which will also be a loss of around 20 to 50 degrees. So how can you achieve a minimum 200 degrees vertical, if you don't start somewhere around 270 horizontal on a full wind?

Incidentally, do you understand why 200 degrees is set as the minimum amplitude for vertical positions after 24 hours? One big reason is the sensitivity to heavy spots on the balance. At exactly 220 degrees, poising errors do not affect timing. Below 200 degrees, the effect of poising errors increases rapidly. So keeping amplitude above 200 degrees for all positions over 24 hours makes a significant contribution to good timekeeping, even if the balance assembly is not perfectly poised.

2 hours ago, VWatchie said:

Just seeing the number 270 makes me feel slightly depressed as it almost made me give up on this wonderful hobby before I knew better.

It's a shame you got so hung up on it back then, but don't let that stop you from using it to your advantage from now on.

2 hours ago, VWatchie said:

I think this quote says most of it!

Interesting that you omitted the part of the quote which made clear that he's talking about an exception!

 

What about some documentation to which you do have access? What books do you have? De Carle's Practical Watch Repairing and Gazely's Watch and Clock Making and Repairing both mention the importance of at least 3/4 turns of the balance (in one direction, i.e. 270 degrees) on a full wind. This was back in the day before timing machines, so it was easier to visualise fractions of a rotation than degrees.

Jendritzski's The Swiss Watch Repairer's Manual is more modern, but again you can find him talking about the importance of 270 degrees horizontal (and enlighteningly, the 220 degrees vertical).

Maybe you have some different books, but most of the "general introduction to watchmaking" works will probably mention it.

 

[VWatchie]

1 hour ago, praezis said:

Else you will have to wait for 24 h after each measure?

As an enthusiast, I'm usually not in a hurry, but if I were in a hurry or too impatient I would unwind the mainspring from a full wind. The number of turns on the ratchet wheel would have to be calculated, but it's not rocket science.

59 minutes ago, Klassiker said:

Interesting that you omitted the part of the quote which made clear that he's talking about an exception!

I feel that the tone is somewhat confrontational but I have no desire whatsoever to get into an argument about this. My starting point is to promote and broaden my own and others' knowledge and at best to encourage those who may think that an amplitude below 270 degrees is a clear sign that something is wrong.

[rehajm]

1 hour ago, Klassiker said:

Interesting that you omitted the part of the quote which made clear that he's talking about an exception!

…and if I understand correctly the reason for low amplitude is a sub optimally sized hairspring. Something that can be remedied. The repairer makes a judgement the watch will be accurate as is and elects to leave the correction until a future service…but it is a still a validation of what the number can tell us. 

[caseback]

Back to my original post .

I got the tool.

 

It allows you to very accurately set the jewels of a pallet fork to the same depth as those of a "standard", but only one jewel at a time. You place the pallet fork (upside down) that is your "standard" and turn the knob on the right side which moves the hammer-shaped arm, which then pushes against the pallet fork, causing the jewel to push against a stud that then makes the pointer move to a random value. After that you do not turn the knob anymore. The device is then set to the entry or exit jewel of your "standard". You can now place another pallet fork of the same type of movement and adjust its entry or exit jewel until the pointer indicates the "standard" value you set.  Nice device, but only useful perhaps if you have a kind of production situation where you want to set the pallet forks of multiple identical movements to a "standard". Not something I expect to do. This tool won't replace my copper coin .