Thank you so much for this tutorial. I purchased a similar clock and was confused because the previous owners must have replaced the Hermle movement with this one and had old directions on the back panel. It was running a few minutes slow every 24 hours and I was finally able to adjust it properly!
Hi James, the way I do it is I make an even amount of turns so, for example, turn the screw four times wait 24 hours and see what’s changed your eventually get down to the point where you’ll start gaining time at that point in time you’ll know, it’s between those last four returns that you made and you can start turning back to then eventually turning back one. I hope you understand and I’m sure it work out for you. It’s better that the clock is running slow then fast.
I have lost count of how man counter-clockwise rotations I have made to adjust this and the clock still runs slow. Is there a limit to how many rotations the adjustment screw will travel before something is damaged?
I have an old 340-020A movement that my dad and I put together, 1969/70 or so. The problem is it runs extremely fast. Gains 15+ minutes a day. I've even slid the spindle off the screw, and it still runs extremely fast. Does it need a good cleaning, replaced, or a professional? Any advice would be appreciated. Thank you.
It sounds like your movement needs a complete overhaul or it can be replaced. The German company still makes that movement. After 50+ years it has done well. Let me know I can get you the replacement movement.
I recently restored a Hemle 340-020A movement with a floating balance. It had the same issues as yours, it ran too fast no matter how slow I adjusted the floating balance + or -. Thinking I had an issue with the floating balance assembly I ordered the newer non floating balance assembly replaced it and the clock still ran fast. All pivots were within specification and none of the forums offered any advice other than adjusting the escape fork pivots further apart. This did nothing. Eventually I turned to the upper portion of the escape fork assembly and how it interfaced with the balance wheel shaft. What I found is by gently adjusting the upper fork to the left, the clock beat slowed. When doing this adjustment, if you dare, bend the upper fork mere millimeters. One can easily break the escape fork by doing this adjustment. Take it slow. My clock now runs perfect.
