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Help needed understanding ETA 2824-2 timing machine results


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The below two images are from before (1st "dark" image) and after (2nd image) service and regulating a 17 jewels ETA 2824-2. Looking at the pallet fork in strong magnification 40X, the pallets, guard pin, and the roller impulse pin all look fine and sits solidly. There is definitely side shake and end shake of the pallet fork, escape wheel and the train wheels, but if it's too much I can't determine with my limited experience. Any idea of what to do or investigate?

 

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Unless a  jewel is broken, faulty side shakes on pallet fork arbor and staff are unlikely, I wouldn,t think a problem exist there.

Make sure upper and lower jewels ( in chaton) endstones are not loose( in the housing)  and shock springs are holding the jewels in place.

Endshake ( axial) on staff is too much if the pivot jumps out of the jewel as you gently lift one side of the balance wheel with tweezers.

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29 minutes ago, VWatchie said:

Good point and you're probably right as I now have three sources stating 53 degrees; you, watchweasol, and Caveman's Watch Forum. LEPSI states 50 degrees.

No matter what it is looks like you've lost some amplitude, let it run a day and re-check.

There still still some spurious beats - but that can be noise picked up, try adjusting sensitivity and with the mov.t inside or outside the case. 

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7 minutes ago, jdm said:

No matter what it is looks like you've lost some amplitude, let it run a day and re-check.

There still still some spurious beats - but that can be noise picked up, try adjusting sensitivity and with the mov.t inside or outside the case. 

Good point! The reading is taken just a minute or so after I had assembled the balance and wound it. I believe I read somewhere you should let the movement "run in" for a day or so before assessing its performance after a service, right?

I'm certainly no timing machine expert (or I wouldn't need to ask) but by "adjusting sensitivity" do you mean the "Gain" of the timing machine (Weishi 1900)?

So, it can make a difference if the movement is measured inside or outside the case, huh? Can you tell me more about that? At first thought, it doesn't seem to make sense...:huh: Note, I'm not questioning it, I'm merely curious and wish to know more!

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24 minutes ago, aac58 said:

There's a big list here: https://watchguy.co.uk/cgi-bin/lift_angle

In it the 2824 is listed as 53º, and 2824-2 as 50º

So, there we have it! Both are right it would seem! Mine is a 2824-2, so 50 degrees after all! Thanks! Oh BTW, the correct link is: https://watchguy.co.uk/cgi-bin/lift_angles

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1 hour ago, VWatchie said:

Good point! The reading is taken just a minute or so after I had assembled the balance and wound it.

For best testing let it on an automatic arm (ideally cyclotest type, these are cheap from China, not collector's winder) and check again the following day, give time to oil to spread evenly. You will have it right for regulation and have tested winding too.

Adjust gain (which compensate microphone sensitivity) to where you have less noise. Mov't Inside or outside can have strange effects depending on case type but in the end a bad patter is bad.

Edited by jdm
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Can too much oil on pallets cause a drag strong enough to account for that much loss of amplitude. Or wrong oil?

2 hours ago, VWatchie said:

Good point and you're probably right as I now have three sources stating 53 degrees; you, watchweasol, and Caveman's Watch Forum. LEPSI states 50 degrees.

What are your sources for lift angles?

This source just list eta2824 dosn,t get into variants.I just assume all variants of same caliber lift the same angle.:rolleyes:

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The lift angle is not the issue one side of the beat is not correct. It could be a loose impulse jewel, a loose pallet jewel, a dirty pallet jewel or a dirty escape wheel. My first effort to resolve this is to check the pallet jewels for damage and tightness and if OK I would just clean again and lubricate again. Its amazing how the smallest amount of unwanted dirt can effect the performance.

On a side note I very rarely bother to adjust the lift angle setting on the timographer unless I suspect it is way out. A smooth pattern on both sides of the beat and a decent amplitude is my goal. 

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9 hours ago, watchweasol said:

Hi  Just done a run through of the lift angles:-  

Watch Guy    2824  =  53    2824-2  =  53
caveman      2824   =   53
lepsi              2824   =   50

As mentioned above, the 2824-2 lift angle is 50°, see attached document. Many people makes no distinction between 2824 and 2824-2, which are different in that and few other details.

_C_T_CT_2824-2_FDE_481688_24.pdf

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15 hours ago, jdm said:

For best testing let it on an automatic arm (ideally cyclotest type, these are cheap from China, not collector's winder) and check again the following day, give time to oil to spread evenly. You will have it right for regulation and have tested winding too.

Adjust gain (which compensate microphone sensitivity) to where you have less noise. Mov't Inside or outside can have strange effects depending on case type but in the end a bad patter is bad.

So, just to make sure, do you think this one would be OK? Seems to be a copy of a Bergeon product costing $1000!

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32 minutes ago, VWatchie said:

So, just to make sure, do you think this one would be OK? Seems to be a copy of a Bergeon product costing $1000!

Yes, when I say that Swiss tool prices are robbery when it's the same product possibly made by same factories, there is always someone coming back with the "quality tools" mantra, without specifying supporting reasons. That being said, of course the Swiss make many tools and machines that nobody else makes, or not to the same standard.

There is also a more practical 3 arms type for something more https://www.aliexpress.com/item/-/33035432640.html

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15 hours ago, Nucejoe said:

Can too much oil on pallets account for such drop in amplitude?

I couldn't say, but I would guess yes! watchrepairlessons.com shows a very convenient and exact way to oil the pallets which I practice.

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1 hour ago, jdm said:

Yes, when I say that Swiss tool prices are robbery when it's the same product possibly made by same factories, there is always someone coming back with the "quality tools" mantra, without specifying supporting reasons. That being said, of course the Swiss make many tools and machines that nobody else makes, or not to the same standard.

There is also a more practical 3 arms type for something more https://www.aliexpress.com/item/-/33035432640.html

Thanks for confirming!

Hm... your option is twice as expensive but looks somehow more convenient/smaller. However, it seems to lack a hook for hanging it on to a wall which will spread the oil more uniformly. Nothing a handy person can't handle I guess, but I'm unfortunately not that type of person.

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6 hours ago, jdm said:

As mentioned above, the 2824-2 lift angle is 50°, see attached document. Many people makes no distinction between 2824 and 2824-2, which are different in that and few other details.

_C_T_CT_2824-2_FDE_481688_24.pdf 6.89 MB · 3 downloads

My impression is that 90 % or more of all the ETA 2824 watches that I look at have the 2824-2 type of movement. Anyway, good that we have now unambiguously established that the lift angle of the 2824-2 is 50 degrees.

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16 hours ago, clockboy said:

The lift angle is not the issue one side of the beat is not correct. It could be a loose impulse jewel, a loose pallet jewel, a dirty pallet jewel or a dirty escape wheel. My first effort to resolve this is to check the pallet jewels for damage and tightness and if OK I would just clean again and lubricate again. Its amazing how the smallest amount of unwanted dirt can effect the performance.

On a side note I very rarely bother to adjust the lift angle setting on the timographer unless I suspect it is way out. A smooth pattern on both sides of the beat and a decent amplitude is my goal. 

Thanks clockboy!

The impulse jewel and the pallets are spotless, in perfect condition (as far as I can see in my stereomicroscope) and as tight as can be. The escape wheel is spotless and has some end shake and side shake. The pallet fork jewel holes are spotless as well. I will try JDMs suggestion to give it a solid day or so of running and then assess it again (experimenting with the Gain gauge), inside and outside of its case. If it doesn't help I'll re-clean and re-lubricate.

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I have looked a little bit on those two pictures you posted and would initialy say the represent two different symtoms.
The upper one suggest the exit stone on your pallet has some dirt or something on it.
The lower picture suggests the hairspring is toutching something, it's a typical signal of that phenomena.


 

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7 hours ago, HSL said:

I have looked a little bit on those two pictures you posted and would initialy say the represent two different symtoms.
The upper one suggest the exit stone on your pallet has some dirt or something on it.
The lower picture suggests the hairspring is toutching something, it's a typical signal of that phenomena.


 

I can confirm that you are right about the dirt on the pallet stone. The movement was indeed in need of a service.

I'm wearing it on my arm as I write this. I'll assess it in a day or two. If the symptoms remain I'll have a very close look at the hairspring. Thanks! :) 

Edited by VWatchie
Tired, writing BS
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