Hi Check the gong hammer assembly is free, lift each individual hammer and check that it drops smartly not in slow motion, It they are sticky dfismantle and free off. Remove the floating balance unit and clean in Alchohol or the like, There is a good explanation on the floating balance on the net by Howard Millar. I will have a look in the Hermle Manual regarding your mode. l do like Hermle clocks very well made. Then Proceed as explained by Old Hippy, sound advise as always.
So, finally, the trigger has been pulled! After many considerations, I decided to order a brand new Bergeon 5500. You can see it here. Shipping included I paid £128/€144/$162. Not a bargain, but reasonable, I guess. I saw some definitive advantages:
* Well tested professional tool. Meaning there's a good chance it will work and work well.
* I can shop individual Bergeon dies for various needs as I go (silly expensive, as always), or shop a good quality Aliexpress set.
* Shipping within Europe so it should be here within a couple of weeks rather than a couple of months (China).
* Seller has 99.9% positive feedback ("Top-rated seller/eBay Money Back Guarantee).
I'll let you know what I think when I've tried it!
Finally, a big thank you to all of you sharing your experience, knowledge, and opinions in this thread! This is what makes WRT such a great place to be.
I recommend against that for user as screwdriver because it's way too fat and heavy, proper watchmakers driver are thin and light to get a good feeling. Cousins UK have "value" which means copied with attention. Same has Ofrei. I used Indian drivers for years without any problem on Seiko, but that's because these have wider slots than Swiss. Now I'll be getting some brand drivers when bought individually they aren't even that expensive. Very good ones are France made, A*F and others I'm sure can be found for a discount. Then I treated myself to the below, Ebay 202315546239, very nice finishing, handy dressing stone and a storage for blades. It's much better than a flimsy plastic chrome rotating stand that comes with cheap sets.