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Deggsie

Help with Amplitude Please

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The keeper plate or gear bridge may have been previously shimmed up, the shim gets washed away during the clean and you wont notice it. A bodge solution that works but you can hardly take pride in it. ALSO, I take another look at cap jewels on both side, are they flat or concave,if flat a concave one may save you the trouble of pivot shortening.Bridge lay out looks similar to fhf28, I think you may find concave cap jewels out of fhf28. As said moving end stones is a bad idea as they are known to fall off and wonder loose inside the movement in a couple of month.

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The keeper plate or gear bridge may have been previously shimmed up, the shim gets washed away during the clean and you wont notice it. A bodge solution that works but you can hardly take pride in it.ALSO, I take another look at cap jewels on both side, are they flat or concave,if flat a concave one may save you the trouble of pivot shortening.Bridge lay out looks similar to fhf28, I think you may find concave cap jewels out of fhf28.As said moving end stones is a bad idea as they are known to fall off and wonder loose inside the movement in a couple of month.

Hello Nucejoe. This topic has really taken off again all of a sudden. My route forwards is buy another movement, exactly the same calibre, and start to swap out one-by-one the following parts:-

1. Top and bottom end stones
2. Escapement
3. Bridge

One of these absolutely must correct the problem, when it does I can investigate the difference and politely identify the fault. This may not be the way forward for an expert with all the tools to his hand, but to an engineer the logical approach will certainly isolate the problem and I will learn from it.

Fortunately a second ‘running’ movement will not cost the earth.

Stay safe and keep well
Deggsie


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You need to look at the pivot and cap 5 times before you decide to shorten the pivot. If after much examination and a good night sleep, you still feel a need to shorten the pivot, then use a Jacot tool with the right lantern and hole size on the end.  Or a lathe and measure, measure, measure.

You remind me of my dads words... always measure twice and cut once.


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Arriving late to the party would you refresh my memory? So I always like to know what was the condition of the watch in before? Then what have you done to it?
Then looking at this discussion one of the things that's really helpful for diagnosing problems is a timing machine. I know hobbyists are operating under a budget but the Chinese timing machines are very affordable work really well and they let you see things that you really can't see any other way. Then if you're having a problem they are even more helpful.  Or basically I think you're insane to repair watches without a decent timing machine which is now affordable versus what it used to be.
I just find it interesting that the pivot is too long and wondering how that has occurred? Especially if this was a running watch before. Also if the place is ben what is the end shake issue like for the other wheels? Also if you shortened the pivot remember to restore it to its original shape otherwise you're going to have issues because you change the shape of the pivot. Also did you look carefully at the pivots themselves to make sure that there not bent.
 
http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&AS_1194
https://watchguy.co.uk/cgi-bin/lift_angles

Hello John. Thank you for taking the time to write such a detailed reply to my topic. I do have a timegrapher, but seriously you don’t need it to diagnose this issue. Poor amplitude is resolved by simply slackening the escapement end stone keeper plate. Immediately this is done, amplitude is restored.

As already detailed I have swapped the end sones around (dial side to balance side) no difference. If I can find the official length and tolerances for the escapement, I will bet myself it’s within specification. That means the bridge is bent down. But, I’m not going to guess, I’m going to properly ascertain the root cause.

You asked how the watch came to me.... it was a non runner, not running at all and the main spring was incorrect for calibre.

There are poise issues which I will tolerate for now - my learning will not happen in a day .

Keep safe John and thank you for your helpfulness

Kind regards
Deggsie


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You remind me of my dads words... always measure twice and cut once.


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I am a dad and my dad said the same for me, plus I screwed up a few balance staffs by trimming them down too much: lesson learned.


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1 hour ago, jdrichard said:

I screwed up a few balance staffs by trimming them down too much

So, the jacot tool helps you mold a rounded top on the pivot end? Apologies if you already explain this in your jacot tool videos. If so, please let me know and I'll have another, more attentive ;), look. Thanks!

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So, the jacot tool helps you mold a rounded top on the pivot end? Apologies if you already explain this in your jacot tool videos. If so, please let me know and I'll have another, more attentive , look. Thanks!

Yes, you use the lantern end that has many sized holes where the pivot end protrudes and you can use a pivot file or stone to take off material in a flat manner and round the end by angling the pivot file as the part turns.


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1 hour ago, jdrichard said:

Hey, this is my video as well.

Yes I know the last time Balloon chucks came up it was just a fast easy way to show how it's done.

Then for those not familiar with them they also come in  different physical sizes with different hole openings.

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You have a good selection of Horology tools there. If I were your neighbour I would have taken up house burglary by nowI’m very envious. And please keep up the videos I really enjoy them - especially the card tricks

 

Regards

Deggsie

 

 

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You have a good selection of Horology tools there. If I were your neighbour I would have taken up house burglary by nowI’m very envious. And please keep up the videos I really enjoy them - especially the card tricks
 
Regards
Deggsie
 
 
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Thanks. I I did put on a ring thru finger trick. Just look up jdrichard soft ring or removable fingers.

PS: I have a big safe:)


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Hello all. I hope you’re keeping well in these frustrating times. Just to keep you updated on my findings. I bought another AS movement and found the following: -

1. Original problematic escape wheel staff was longer.

2. The bridge on the problematic movement was quite dipped down. Straightening alone wasn’t enough to resolve the issue

3. I straightened bridge and swapped the escapement wheel. The end stone can now be installed tight and minimal end shake is felt.

Result: The movement is now running as well as expected by me with an amplitude of circa 270 degrees. I also have a NOS balance complete on order which will hopefully alleviate the issues of the watch losing amplitude when not in DU or DD position

I’ll post a photo or two when it’s all re-cases and has a nice strap fitted.

Stay safe.

Kind regards
Deggsie



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I think you have nailed it Rodabod. When I was looking for a spare AS1194 I did see that some were built with rubbed in jewels and non Incabloc on the balance wheel. It’s good to get this little niggling problem resolved at last.

Regards
Deggsie


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On 5/17/2020 at 1:10 AM, Deggsie said:

I also have a NOS balance complete on order which will hopefully alleviate the issues of the watch losing amplitude when not in DU or DD position

So, what amplitude are you getting in the other positions? I read/heard somewhere that 220 degrees is the minimum amplitude needed to defeat gravity. I'm certainly not an expert, but I'd say that if you get let's say around 240 degrees in the other positions the amplitude is probably in the acceptable range!? I've been struggling with amplitude myself, a Unitas 6325, and I have now reached approx. 282 degrees dial up/dial down and approx. 246 in all other positions. It's not perfect, but I've decided to call it a day. At my current skill level there's nothing more I can do.

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So, what amplitude are you getting in the other positions?

I have 270 to 280 in DU and DD positions. 210 to 240 in all other positions. The beat error increases when not in DU/DD.

 

For a 1940’s movement I’m happy with this. The hair spring is as well formed as I can get it and I fear if I tweak it any more it may fatigue and break.

 

Poising is definitely out, but I shall not be trying to rectify that just now as I don’t have the correct tooling. All that will come later - hopefully

 

Have you considered installing a new mainspring? That is after all the root of all energy in the watch. The stored spring energy is converted to kinetic energy in the balance minus some losses due to sound and kinetic energy required to move the indicators (hands).

 

 

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3 hours ago, Deggsie said:

I have 270 to 280 in DU and DD positions. 210 to 240 in all other positions. The beat error increases when not in DU/DD

Well, for a 1940s movement and if it is somewhat consistent over time, i.e. not dropping in amplitude too much after 24h of a full wind, I'd say that's probably as good as it is going to get, unless you take some sort of drastic action, but I see no need for that. I think you're done with it. Congrats! :thumbsu:

3 hours ago, Deggsie said:

Have you considered installing a new mainspring? That is after all the root of all energy in the watch.

Not sure if I mentioned my Unitas cal. 6325 in this thread but I guess I did!? If that's what you're referring to then yes that's exactly what I did. However I made a hole array of adjustments and if interested I've listed them in this post.

Edited by VWatchie

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