You wouldn't know it to look at them. The only real visible difference would be in the hairspring and presumably the gearing. I needed a balance for a 620 and bought a lot of four movements on eBay. I was really surprised when one of them was beating at 21,600.

 

Well, the wheel train ratios would be different for sure. Not only would the hairspring be different, but the balance wheel diameter would probably be smaller too.

 

Steve,
I notice your photos are very clear. It was very difficult for me to get decent shot in that environment.
Do you have complete pictures of all watches in Museum?

 

Errr... I hate to steal your thunder there Cicindela but I posted about these in April last year

http://omegaforums.net/threads/at-the-omega-museum-today.5159/#post-60676

 

it's unbelievable to me that they didn't capitalise on those early prototypes. The landscape of Omega history might look very different if they had.

 

There would be a lot of differences...

Mainspring would likely be much stronger, all the wheels would have to be changed to the correct ratios, so from the barrel right to the escape wheel. It's possible that pallet angles would have to be modified, and even though the balance wheel might not necessarily be made smaller, the strength of the balance spring would have to increase.

One reason these companies had to study this before implementing it is because these watches do tend to wear faster than slower beat movements do. Also at the time these experiments were done by the various brands, there was no such thing as Moebius 9415, which is what most watchmakers (who have moved into the 20th century anyway) use on the escapement. It is a thixotropic grease that stays put on the pallet fork jewel and escape wheel teeth, and is much less likely to be thrown off these surfaces at the high speeds required by the high beat escapements then just a regular oil would be.

High beat is a trade off like most things in watch design.

Cheers, Al

 

Thanks Al, for the word of the day - "thixotropic"!

 

Thixotropic substances are usually no further away than the pantry or refrigerator - ketchup is a good example, although likely not suitable for lubricating watch escapements.

The 9415 is applied in a state that looks like grease, and this gives it the ability to cling onto the escape wheel teeth and pallet fork jewels very well compared to oil. However when it's under pressure of the contact forces and sliding motion of the jewel on the tooth, it becomes very fluid and does a great job at lubricating this interface.

Originally stated as something to be used in high beat escapements (28,800 and above) it is now widely used for all speeds. I use it on everything from 18,000 on up. Of course excluding co-axials and some other types of escapements, so referring specifically to Swiss lever escapements here.

Glad you found this helpful.

Cheers, Al