Low amplitude on 2836-2

[centerwheel]

I am doing service on a ETA 2836-2 (Sellita 220-1) movement. This is to practice, the movement is new. At this stage I have the movement still without calendar and without automatic winding. Everything has been cleaned, oiled, the pallets oiled then cleaned again. Mainspring removed, cleaned, breaking grease applied to barrel sidewall, mainspring put back (using wider), and finally oiled in the barrel. The arbor bearings were oiled, as well as the barrel bearings. The problem is low amplitude. The photo is for a fully wound watch in dial down position. The dial up shows the amplitude dropping to 170 degrees, which is 29 degrees less than dial down. I am thinking that this may be balance related. Should I take the balance out, clean it, clean the balance jewels, oil them, and see if this helps? Any other suggestion would be also very appreciated.

[Nucejoe]

     Are you sure enough lubricant did get on escape teeth?   Also What lube there? and how much? 

Full distribution of lubricant on escape teeth may take couple days of running.

If you suspect too little lube on escape, a test would be direct application of lube, as the movement is running. 

No lube on fork arbor.

 

 

[centerwheel]

Thanks for the suggestion. I agree that the pallets oiling might have caused this. Either too much or not enough oil. I used Moebius 9415 applied to the impulse face of the entry and exit pallets. I let then the movement run for a few minutes, then took the pallets off and clean it before reinstalling.

Question: How do you apply lube on an escape wheel while the movement is running? I've never seen it done.

[jdm]

This seems more an end shake problem to me.
Have you checked it on the instrument before taking it apart?

Edited November 2, 2019 by jdm

[meanoldmanning]

Question: How do you apply lube on an escape wheel while the movement is running? I've never seen it done.  

 

It’s called dynamic oiling. Rolex started recommending the method several years ago. You basically have the mov’t running and dab oil onto the face of a tooth through the inspection port from the dial side. It is pretty tricky and requires high magnification and lighting from under the mov’t. There are a few vids on YouTube that show it. There’s one in particular that demonstrates it really well. I’ll see if I can find it.   

 

EDIT - found it. Dynamic lubrication part starts around 40:29

 

https://www.youtube.com/embed/Xnh7O22mduE?feature=oembed]  

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