ETA 2772: Hour hand and minute hand stop rotating

[VWatchie]

ETA 2772: The hour hand and the minute hand intermittently stop spinning at 12:30, but not the seconds hand which keeps going. When setting the time, the cannon pinion feels very loose. Can I safely assume that I need to replace the cannon pinion with driving wheel to remedy this, or could there be some other explanation? I believe I read here on WRT that this type of ETA cannon pinion (with driving wheel) can’t be tightened or is extremely difficult to tighten and must be replaced. Correct?

[rogart63]

Some wheels can be tighten. But usually best is to replace . I think it's the one with 3 arms on a 2772? I have tighten a few of those . A large round stake. And give it a small blow with a hammer . And turn it around. That works . But not sure how long as the wheel gets thinner in the middle . Could give each arm a small blow to with a thin round stake . But it's harder to get the exact same on all arms. If not the wheel will wobble. 

Edited March 3, 2020 by rogart63

[Nucejoe]

Isn't Canon pinion mounted on the driver wheel?  

If you oiled the groove on Canon pinion, just rinsing the oil off may work.

Cost free to text.

Edited March 4, 2020 by Nucejoe
Correction test not text.

[JohnR725]

Have you disassemble the watch to verify what the problem is?  What I've seen happen on other watches using this design is if the canon pinion part doesn't rotate the drive wheel will slip and eventually wear itself out. Occasionally flipping that wheel over and putting it back on again works. Tightening as noted above sometimes works if you're careful. By far replacing it would be the best if it's available.

 

 

925_ETA 2770, 2772, 2782.pdf

[VWatchie]

On 3/5/2020 at 11:59 AM, JohnR725 said:

Have you disassemble the watch to verify what the problem is?

I have disassembled the watch but as the problem is intermittent I could not easily verify. Anyway, it would seem that the slipping theory is the most plausible idea. Fortunately cousinsUK had this part for sale. It comes in various heights but many of the heights are restricted and hence not for sale. Fortunately, the height I needed, 2.45 mm, was available for about £8.5 (incl. tax).

Edited March 7, 2020 by VWatchie
typos

[VWatchie]

So, I replaced the cannon pinion with driving wheel which seems to be typical for many ETA movements. The ETA calibres that I have serviced like the 955.112,  2472, 2772, and the 2824-2 have this kind of cannon pinion.

However, the new cannon pinion was sitting so tight on the driving wheel that it wouldn't slip when setting the time anticlockwise . That is, the seconds hand would move anticlockwise (the train being forced backwards) which could potentially damage the movement. The ETA cal. 2772 is non-hacking and has no date corrector so to "quick set" the date the hands must be turned back and forth between 9 and 12. So for this reason I felt that this was a real problem.

I had lubricated the cannon pinion/driving wheel rather sparingly but in my mind sufficiently. Still I had the feeling that I just might have under oiled it (I know, it sounds strange ). So, I decided to take it out and oil it some more (Moebius HP-1300) just to see what effect it would have. Well, at first it didn't seem to help at all (watch wound down), but after having wound it a few turns I tried again and to my surprise the seconds hand kept ticking clockwise while I was turning the hands anticlockwise. So, problem solved! I guess the barrel must have some power to be able to resist the driving wheel.

So, my conclusion is; make sure not to under oil the ETA cannon pinion with driving wheel. Just thought I'd share my experience.

 

[watchweasol]

Interesting,        as the general problem is with movements over oiled  ,or not oiled at  all.  cheers for that.            

[VWatchie]

On 5/24/2020 at 1:32 PM, watchweasol said:

Interesting,        as the general problem is with movements over oiled  ,or not oiled at  all.  cheers for that.            

By a coincidence I just saw this section of Mark Lovicks ETA 955.412 service video, and it definitely confirms my previous post, i.e. there is a real risk to under oil the cannon pinion with driving wheel. So, just spoon-feed that sucker with oil! 

[JohnR725]

Typically on canon pinions we use grease and that's what I use on these also.

[VWatchie]

1 hour ago, JohnR725 said:

Typically on canon pinions we use grease and that's what I use on these also.

In this case I followed ETA's technical communication document for calibre 2824-2 which is very similar in this respect to the 2772. However, in Mark Lovick's watch repair lessons and in his videos (my main source) it would seem he mostly (always?) uses Moebius 9501 or 9504 grease for the cannon pinion and the driving wheel. I suppose it may be a better option if epilame hasn't been applied as specified in ETA's technical communication? (never saw Mark use or mention epilame)

[jdm]

I

On 5/24/2020 at 12:58 PM, VWatchie said:

 

So, I decided to take it out and oil it some more (Moebius HP-1300) just to see what effect it would have. Well, at first it didn't seem to help at all (watch wound down), but after having wound it a few turns I tried again and to my surprise the seconds hand kept ticking clockwise while I was turning the hands anticlockwise. So, problem solved!

I use only HP-1300 of the cannon pinion as I don't have or care for the expensive products that are on the service sheets. Works fine for me, never had a problem nearing 5 years now.

 

[VWatchie]

13 hours ago, jdm said:

I use only HP-1300 of the cannon pinion

 

13 hours ago, jdm said:

Works fine for me, never had a problem nearing 5 years now.

Good to know you've had good results using HP-1300 on the cannon pinion even without the epilame (Fixdrop) treatment.