Hi everybody

Searching mighty Google and the forums here, I was not able to find information about the lift angle of the calibre 3861 inside the new moon watches. This seems a bit odd, as I would expect such information to be published in service manuals or the like. Yet, the lift angle of the 3861 seems to be unknown.

Does anybody know more?

 

It's based on lemania1873. Which is 50deg. I'd start there.
The only googling I find says Unconfirmed (use Co-Axial compatible timing machine).
I suppose you could call an omega dealer Maybe we'll get someone polite on the phone that could help you.
Good luck, keep us posted.
I'll keep a record of all the lift angles of any watch I've had as I time them all...
Cheers.

 

If I recall, the escapement used in the 3861 is identical to the 8800 model. Since my understanding is that lift angle is a trait of the escapement, that may be more relevant than the Lemania spec.

 

36 degrees. But unless you have a timing machine that has a specific program for measuring co-axial escapements, the amplitude reading you get will not be accurate.

 

Thanks Archer! Very much appreciated. So, the 3861 is a little bit different from the other modern co-axial movements then. Bonus question (which is closely related ): The 3861 in my Snoopy gains about 5 seconds per hour when I’m wearing the watch while taking a (fast but not running) walk. The watch runs perfectly fine at around +1 second a day (across all positions) when it sits still. In comparison, my Seamaster (8912) does not gain extra time while walking.

I’m wondering if this is a problem with my 3861 or with the 3861 in general. As I understand the 3861 is more of a co-axialized seasoned movement (and also running at a slower rate) than a completely modern co-axial movement. Still, such a noticeable gain seems wrong in a modern watch. Writing this makes me wonder if it were normal/acceptable for a 321 based Speedmaster with its even lower movement frequency...

 

Thanks, but I think the co-axial part makes it differ in lift angle from its ancestor(s).

 

This sort of thing can be caused by the swinging of your arm disturbing the balance wheel, causing it to beat faster.

It's not unheard of certainly, but I wouldn't consider it normal.

 

Thanks Archer. So this is not a known problem of the 3861 but probably a problem with my watch (or my way of swinging the arm) and I should have Omega take a look at it (at the watch, not the arm ;-) ).

 

As far as I know, it's not a known issue with the 3861.

Are you fully winding the watch every day?

 

Yes, I usually do.

After noticing an unexpected gain (after taking a walk) for the first time, I explicitly measured two other walks. One was with a fully wound watch, the other a bit past half wound. In both cases the watch gained several seconds per hour.

 

I noticed comparable gains even previously, but then I would not relate the gains to taking a walk. I just thought I'd forgotten to wind the watch and maybe it had been running on low tension. In hindsight this does not seem to be the reason.

 

Have you tried speed walking with your arms above your head?

 

No, I won't be able to hold my arms above my head for 1.5 hours :-P
(Also, I'm not really speed walking, just a bit faster than a relaxed recreational walk)

 

Perhaps running with your arms folded across your chest then?

 

Thanks for the instructional videos on how to improve my moves in order to improve the 3861's accuracy. I'll let you know which one worked best. In addition, I just booked an instructional session at the ministry of silly walks with John Cleese to learn from the best.

 

Gee, and I thought I would be a smart ass and say "Maybe you should give up walking". Tough crowd.

 

To answer my own question from above in regards to what could be expected from a Speedmaster 321 under the same conditions: The Speedmaster 321 was unimpressed. It did not really gain or lose time during the walk in comparison to the previous hours spent doing office work and housework. So the old movement beats the new one ;-) But I think only because my sample of the new one is defective...