This change to bronze bushings and hardened (larger) pivots was made long ago. Plates are still about 1.6 mm and the bronze bushings are 2.1 mm. The new pivots are made for the new factory installed bushings and there will be no problem In this area. The new 2nd arbor/wheel assemblies can be retro fitted to older movements for an upgrade. However, I would not recommend using the very large Hermle bronze bushings. Use the much smaller KWM #89. Or, if tje plate is worn over badly, use the larger KWM #45. Usually, only the back (wheel end) will need a bushing. The pivots are larger so the other end can usually be slightly broached and you're good to go. Maybe this should be a new thread? WIllie X
That's interesting, and thank you. I wonder why I've never seen any--either brought in for repair or in a museum or collection. Mark Kinsler because I live in the middle of the corn belt
My view on the bushings, maybe wrong however, If you look at an Ansonia or the like, the pivots are about double the length of the plate, and I have always had to polish the pivots as they end up with a taper or blob on the end. I use longer bushes when I re-bush, however not past the end of the pivot. I can't see why anyone would put a bush in and then make it flush and put an oil well thus reducing the bush under the thinckness of the plate and compound the issue. I have just posted a clock here Oswald re-found after 10 years Rudolf Valentino the bushes are not flush, however they do not go past the pivot, is this wrong, it looks neat to me.
The bushings certainly look fine to me. I agree with you on bushing length, having in the past worried about their being flush, or sub-flush, or with or without oil sinks. Best evidence seems to indicate that the clock doesn't care, so you might as well leave them longer. Mark Kinsler
The best indicator of how bushings should be done is how the clock was originally made. The method that comes closest to restoring the original condition is the gold standard to which all other methods are compared. RC
This is a fundamental point of contention which probably will never be resolved. Restorers of old automobiles encounter the same issues. Some clocks--and automobiles--were not engineered so superbly. So we do our best, working under the assumption that time takes its toll in many ways. M Kinsler
Generally speaking, when a customer brings in a clock for service they are not looking to have it modified or reengineered. Indeed, modifications could reduce the value of the clock. Of course if it is your own clock you have every right to depart from best practices and try to "improve" your clock or use any "short cut methods" you like to save time increase you enjoyment. RC
Most Hermle spring wound movements come with factory installed bushings in the 2nd wheels. The exceptions are the 130, 131, and 132 series. Hermle also makes the 1050-020 and 340-020 movements both with and without these bushings since they are the largest selling. There is special lower pricing on the non bushed version.
